Steel Castings Handbook

STEEL CASTINGS HANDBOOK SUPPLEMENT 2 2009 SUMMARY OF STANDARD SPECIFICATIONS FOR STEEL CASTINGS

Steel Castings Handbook Supplement 2 Summary of Standard Specifications For Steel Castings - 2009 PREFACE Supplement 2 will be revised at regular intervals. Supplement 2 is only a summary that is useful in comparing the general requirements in different types of specifications. When ordering, an up-to-date original specification should be used.

CONTENTS  

ORDERING STEEL CASTINGS .............................................................................................................................................3  Overview ............................................................................................................................................................................................... 3  Design.................................................................................................................................................................................................... 3  Background ....................................................................................................................................................................................... 3  Minimum Section Thickness............................................................................................................................................................. 3  Draft .................................................................................................................................................................................................. 3  Parting Line....................................................................................................................................................................................... 4  Cores ................................................................................................................................................................................................. 4  Internal Soundness/Directional Solidification .................................................................................................................................. 4  Machining ......................................................................................................................................................................................... 4  Layout ............................................................................................................................................................................................... 5  Material.................................................................................................................................................................................................. 5  Tests....................................................................................................................................................................................................... 6 

SUMMARY OF MATERIAL SPECIFICATIONS FOR CARBON AND ALLOY CAST STEELS ......................................7  AISI Classification System ...................................................................................................................................................... 7  Type................................................................................................................................................................................................... 7  TENSILE REQUIREMENTS ........................................................................................................................................... 21  Class................................................................................................................................................................................... 21 

SUMMARY OF MATERIAL SPECIFICATIONS FOR HIGH ALLOY CAST STEELS ....................................................32  SUMMARY OF MATERIAL SPECIFICATIONS FOR CENTRIFUGALLY CAST STEELS............................................51  SUMMARY OF STANDARD TEST METHODS FOR STEEL CASTINGS........................................................................57  Overview ............................................................................................................................................................................................. 57  Mechanical Testing.............................................................................................................................................................................. 57  Background ..................................................................................................................................................................................... 57  Tension Testing............................................................................................................................................................................... 57  Hardness Testing............................................................................................................................................................................. 57  Impact Testing................................................................................................................................................................................. 57  Nondestructive Examination ............................................................................................................................................................... 58  Background ..................................................................................................................................................................................... 58  Visual Examination......................................................................................................................................................................... 58  Liquid Penetrant Examination (PT) ................................................................................................................................................ 58  Magnetic Particle Examination (MT) ............................................................................................................................................. 59  Radiographic Examination (RT) ..................................................................................................................................................... 61  Ultrasonic Testing (UT) .................................................................................................................................................................. 61 

SPECIAL STANDARD PRACTICES....................................................................................................................................62  Ferrite Content..................................................................................................................................................................................... 62  Welding ............................................................................................................................................................................................... 63 

CODE AND SPECIFICATION AGENCIES..........................................................................................................................64  Lloyd’s Register of Shipping............................................................................................................................................. 64  (LR).................................................................................................................................................................................... 64 

1

Prepared by the SPECIFICATIONS COMMITTEE STEEL FOUNDERS’ SOCIETY OF AMERICA Revised - 2009

Funding for revision of this document was provided by AMC’s Castings for Improved Readiness Program – sponsored by the Defense Supply Center Philadelphia, Philadelphia, PA and the Defense Logistics Agency, Ft. Belvoir, VA.

2

ORDERING STEEL CASTINGS Overview When making inquiries or ordering parts, all pertinent information must be stated on both the inquiry and order. This information should include all of the following components. 1. Casting shape – either by drawing or pattern. Drawings should include dimensional tolerances, indications of surfaces to be machined, and datum points for locating. If only a pattern is provided, then the dimensions of the casting are as predicted by the pattern. 2. Material specification and grade (e.g. ASTM A 27/A 27M – 95 Grade 60-30 Class 1). 3. Number of parts. 4. Supplementary requirements (e.g. ASTM A 781/A 781M – 95 S2 Radiographic Examination). A. Test methods (e.g. ASTM E 94) B. Acceptance criteria (e.g. ASTM E 186 severity level 2, or MSS SP-54-1995). 5. Any other information that might contribute to the production and use of the part. To produce a part by any manufacturing process it is necessary to know the design of the part, the material to be used and the testing required. These three elements are discussed in detail in the following sections.

Design Background To obtain the highest quality product, the part should be designed to take advantage of the flexibility of the casting process. The foundry must have either the part drawing or pattern equipment and know the number of parts to be made. To take advantage of the casting process, the foundry should also know which surfaces are to be machined and where datum points are located. Reasonable dimensional tolerances must be indicated where a drawing is provided. Tolerances are normally decided by agreement between the foundry and customer. SFSA Supplement 3 represents a common staring point for such agreements. Supplement 3 is not a specification and care should be taken to reach agreement on what tolerances are required. Close cooperation between the customers’ design engineers and the foundry’s casting engineers is essential, to optimize the casting design, in terms of cost and performance. Additional guidelines for casting design are given in “Steel Castings Handbook” and Supplement 1,3, and 4 of the “Steel Castings Handbook”. Minimum Section Thickness The rigidity of a section often governs the minimum thickness to which a section can be designed. There are cases however when a very thin section will suffice, depending upon strength and rigidity calculations, and when castability becomes the governing factor. In these cases it is necessary that a limit of minimum section thickness per length be adopted in order for the molten steel to completely fill the mold cavity. Molten steel cools rapidly as it enters a mold. In a thin section close to the gate, which delivers the hot metal, the mold will fill readily. At a distance from the gate, the metal may be too cold to fill the same thin section. A minimum thickness of 0.25” (6 mm) is suggested for design use when conventional steel casting techniques are employed. Wall thicknesses of 0.060” (1.5 mm) and sections tapering down to 0.030” (0.76 mm) are common for investment castings. Draft Draft is the amount of taper or the angle, which must be allowed on all vertical faces of a pattern to permit its removal from the sand mold without tearing the mold walls. Draft should be added to the design dimensions but metal thickness must be maintained. Regardless of the type of pattern equipment used, draft must be considered in all casting designs. Draft can be eliminated by the use of cores; however, this adds significant costs. In cases where the amount of draft may affect the subsequent use of the casting, the drawing should specify whether this draft is to be added to or subtracted from the casting dimensions as given. 3

The necessary amount of draft depends upon the size of the casting, the method of production, and whether molding is by hand or machine. Machine molding will require a minimum amount of draft. Interior surfaces in green sand molding usually require more draft than exterior surfaces. The amount of draft recommended under normal conditions is about 3/16 inch per foot (approximately 1.5 degrees), and this allowance would normally be added to design dimensions. Parting Line Parting parallel to one plane facilitates the production of the pattern as well as the production of the mold. Patterns with straight parting lines, parting lines parallel to a single plane, can be produced more easily and at lower cost than patterns with irregular parting lines. Casting shapes that are symmetrical about one centerline or plane readily suggest the parting line. Such casting design simplifies molding and coring, and should be used wherever possible. They should always be made as “split patterns” which require a minimum of handwork in the mold, improve casting finish, and reduce costs. Cores A core is a separate unit from the mold and is used to create openings and cavities that cannot be made by the pattern alone. Every attempt should be made by the designer to eliminate or reduce the number of cores needed for a particular design to reduce the final cost of the casting. The minimum diameter of a core that can be successfully used in steel castings is dependent upon three factors; the thickness of the metal section surrounding the core, the length of the core, and the special precautions and procedures used by the foundry. The adverse thermal conditions to which the core is subjected increase in severity as the metal thickness surrounding the core increases and the core diameter decreases. These increasing amounts of heat from the heavy section must be dissipated through the core. As the severity of the thermal condition increases, the cleaning of the castings and core removal becomes much more difficult and expensive. The thickness of the metal section surrounding the core and the length of the core affect the bending stresses induced in the core by buoyancy forces and therefore the ability of the foundry to obtain the tolerances required. If the size of the core is large enough, rods can often be used to strengthen the core. Naturally, as the metal thickness and the core length increase, the amount of reinforcement required to resist the bending stresses also increases. Therefore, the minimum diameter core must also increase to accommodate the extra reinforcing required. The cost of removing cores from casting cavities may become prohibitive when the areas to be cleaned are inaccessible. The casting design should provide for openings sufficiently large enough to permit ready access for the removal of the core. Internal Soundness/Directional Solidification Steel castings begin to solidify at the mold wall, forming a continuously thickening envelope as heat is dissipated through the mold-metal interface. The volumetric contraction which occurs within a cross section of a solidifying cast member must be compensated by liquid feed metal from an adjoining heavier section, or from a riser which serves as a feed metal reservoir and which is placed adjacent to, or on top of, the heavier section. The lack of sufficient feed metal to compensate for volumetric contraction at the time of solidification is the cause of shrinkage cavities. They are found in sections which, owing to design, must be fed through thinner sections. The thinner sections solidify too quickly to permit liquid feed metal to pass from the riser to the thicker sections. Machining In the final analysis, the foundry’s casting engineer is responsible for giving the designer a cast product that is capable of being transformed by machining to meet the specific requirements intended for the function of the part. To accomplish this goal a close relationship must be maintained between the customer’s engineering and purchasing staff and the casting producer. Jointly, and with a cooperative approach, the following points must be considered.

4

1. 2. 3. 4. 5.

The molding process, its advantages and its limitations. Machining stock allowance to assure clean up on all machined surfaces. Design in relation to clamping and fixturing devices to be used during machining. Selection of material specification and heat treatment. Quality of parts to be produced.

Layout It is imperative that every casting design when first produced be checked to determine whether all machining requirements called for on the drawings may be attained. This may be best accomplished by having a complete layout of the sample casting to make sure that adequate stock allowance for machining exists on all surfaces requiring machining. For many designs of simple configuration that can be measured with a simple rule, a complete layout of the casting may not be necessary. In other cases, where the machining dimensions are more complicated, it may be advisable that the casting be checked more completely, calling for target points and the scribing of lines to indicate all machined surfaces.

Material The material to be used to produce the part must be identified in the order. Material for steel castings is generally ordered to ASTM requirements, although other specifications may be used. This supplement contains a summary of the scope, chemical composition requirements and mechanical property requirements of these material or product specifications. Many requirements are common to several specifications and are given in ASTM A 781/A 781M, ASTM A 703/A 703M, ASTM A 957, ASTM A 985, and ISO 4990. ASTM A 781/A 781M – 97

CASTINGS, STEEL AND ALLOY, COMMON REQUIREMENTS, FOR GENERAL INDUSTRIAL USE This specification covers a group of requirements that are mandatory requirements of the following steel casting specifications issued by American Society of Testing and Materials (ASTM). If the product specification specifies different requirements, the product specification shall prevail. ASTM Designations: A 27/A 27M, A 128/A 128M, A 148/A 148M, A 297/A 297M, A 447/A 447M, A 486/A 486M, A 494/A 494M, A 560/A 560M, A 743/A 743M, A 744/A 744M, A 747/A 747M, A 890/A 890M, A 915/A 915M, and A 958.

ASTM A 703/A 703M – 97

STEEL CASTINGS, GENERAL REQUIREMENTS, FOR PRESSURE CONTAINING PARTS This specification covers a group of common requirements that, unless otherwise specified in an individual specification, shall apply to steel castings for pressurecontaining parts under each of the following ASTM specifications. ASTM Designations: A 216/A 216M, A 217/A 217M, A 351/A 351M, A 352/A 352M, A 389/A 389M, A 487/A 487M, A 985, A 990, and A 995.

ASTM A 957 – 96

INVESTMENT CASTINGS, STEEL AND ALLOY, COMMON REQUIREMENTS, FOR GENERAL INDUSTRIAL USE This specification covers a group of requirements that are mandatory for castings produced by the investment casting process to meet the metallurgical requirements of the following steel casting specifications issued by ASTM. ASTM Designations: A 27/A 27M, A 148/A 148M, A 297/A 297M, A 447/A 447M, A 494/A 494M, A 560/A 560M, A 732/A 732M, A 743/A 743M, A 744/A 744M, A 747/A 747M, A 890/A 890M, and A 915/A 915M.

ASTM A 985 – 98

STEEL INVESTMENT CASTINGS GENERAL REQUIREMENTS, FOR PRESSURE-CONTAINING PARTS This specification covers a group of common requirements, which are mandatory for steel castings produced by the investment casting process for pressurecontaining parts under each of the following ASTM specifications. ASTM Designations: A 216/A 216M, A 217/A 217M, A 351/A 351M, A 352/A 352M, A 389/A 389M, and A 487/A 487M.

ISO 4990

STEEL CASTINGS – GENERAL TECHNICAL DELIVERY REQUIREMENTS 5

Tests Testing ensures that the material meets the requirements of the specification; consequently, testing is mandatory. More frequent testing or other tests may be imposed by use of supplementary requirements of product specifications or general requirement specifications. The least testing done consistent with the goals allows for the most economical product. In addition to specifying test methods, acceptance criteria must be agreed on. The more testing and tighter the acceptance criteria, the more expensive the steel casting produced, without necessarily increasing the quality or serviceability of the steel casting. Hence, the extent of testing and acceptance criteria should be based on the design and service requirements. The mechanical properties required are obtained from test bars cast separately from or attached to the castings to which they refer. The mechanical properties obtained represent the quality of steel, but do not necessarily represent the properties of the castings themselves. Solidification conditions and rate, if cooling during heat treatment, affect the properties of the casting, which in turn are influenced by casting thickness, size, and shape. In particular, the hardenability of some grades may restrict the maximum size at which the required mechanical properties are obtainable.

6

SUMMARY OF MATERIAL SPECIFICATIONS FOR CARBON AND ALLOY CAST STEELS

The American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code makes extensive use of the ASTM specifications with slight modifications. For the sake of comparison, the ASME specifications use the preface SA so that SA 216 is related to ASTM A 216/A 216M. However, while ASTM A 216/A 216M could be used for the sake of comparison of grades, ASME SA 216 contained in Section II, must be used when complying with the code. The American Iron and Steel Institute (AISI) and the Society of Automotive Engineers (SAE) developed a four number wrought alloy designation system, which is used extensively. These steels have been identified in the AISI classification by a numerical index system that is partially descriptive of the composition. The first digit indicates the type to which the steel belongs. A “1” indicates a carbon steel, a “2” indicates a nickel steel, and a digit greater than “2” indicates alloys other than nickel or alloy combinations. For low alloy steels, the second digit indicates the approximate percentage of the predominant alloy element. Usually the last two or three digits indicate the average carbon content in “points”, or hundredths of a percent. Thus, “2340” indicates a nickel steel of approximately 3% nickel (3.25 to 3.75) and 0.40% carbon (0.38 to 0.43). The basic numerals for the various types of AISI steels (including plain-carbon steels) are listed in the table below. The basic numbering system adopted by the Society of Automotive Engineers is quite similar, differing only in minor details. The SAE Handbook should be consulted for comparison. AISI Classification System Series Designation 10xx 11xx 12xx 13xx 15xx 23xx 25xx 31xx 33xx 40xx 41xx 43xx 44xx 46xx 47xx 48xx 50xx 51xx 5xxxx 61xx 81xx 86xx 87xx 88xx 92xx 93xx B BV L

Type Nonresulphurized carbon steel grades Resulphurized carbon steel grades Rephosphorized and resulphurized carbon steel grades Manganese 1.75% Manganese over 1.00 to 1.65% Nickel 3.50% Nickel 5.00% Nickel 1.25% - Chromium 0.65% Nickel 3.50% - Chromium 1.55% Molybdenum 0.25% Chromium 0.50 or 0.95% - Molybdenum 0.12 or 0.20% Nickel 1.80% - Chromium 0.50 to 0.80% - Molybdenum 0.25% Molybdenum 0.40 or 0.53% Nickel 1.55 or 1.80% - Molybdenum 0.20 or 0.25% Nickel 1.05% - Chromium 0.45% - Molybdenum 0.20% Nickel 3.50% - Molybdenum 0.25% Chromium 0.28 or 0.40% Chromium 0.80, 0.90, 0.95, 1.00 or 1.05% Carbon 1.00% - Chromium 0.50, 1.00 or 1.45% Chromium 0.80 or 0.95% - Vanadium 0.10% or 0.15% min. Nickel 0.30 – Chromium 0.40 - Molybdenum 0.12 Nickel 0.55% - Chromium 0.50 or 0.65% - Molybdenum 0.20% Nickel 0.55% - Chromium 0.50% - Molybdenum 0.25% Nickel 0.55% - Chromium 0.50% - Molybdenum 0.35% Manganese 0.85% - Silicon 2.00% Nickel 3.25% - Chromium 1.20% - Molybdenum 0.12% Denotes boron steel (e.g. 51B60) Denotes boron-vanadium steel (e.g. TS 43BV12 or TS 43BV14) Denotes leaded steel (e.g. 10L18)

Needless to say, this list representing as it does, a standardization and simplification of thousands of alloy-steel compositions, is a very valuable aid to the specification and choice of alloy steels for various applications. Many of these steels were developed for specific applications, and their continual satisfactory performance has resulted 7

in a considerable degree of standardization of application among these compositions. These designations can be ordered in castings through the use of ASTM A 148/A 148M, A 915/A 915M, or A 958 but care must be used to select a grade with compatible mechanical properties. Also the wrought composition must be modified, especially the silicon and manganese content to allow for casting. Below is a list of carbon and alloy cast steel specifications, with summary details on the following pages. Note that the values given in the summary of the specifications are stated with either U.S. Conventional Units (USCS) or Metric (SI) units, and are to be regarded separately. Units given in brackets are SI units. The values stated in each system are not exact equivalents (soft conversion); therefore, each system must be used independently of the other. Combining values from the two systems, by using conversion equations (hard conversion), may result in nonconformance with the specification. Also note that the values in the table are given in a minimum over maximum format. This means that if the value is a minimum it will be listed in the upper portion of the specification’s table row and in the lower portion of the row if it is a maximum value. Finally, note that tables and their footnotes may be split across two or more pages. AAR M-201-92 ABS 2/1.5 ABS 2/3.9 ASTM A 27/A 27M – 08 ASTM A 148/A 148M – 08 ASTM A 216/A 216M – 07 ASTM A 217/A 217M – 07 ASTM A 352/A 352M – 06 ASTM A 356/A 356M – 07 ASTM A 389/A 389M – 08 ASTM A 487/A 487M – 07 ASTM A 597 – 04 ASTM A 732/A 732M – 05 ASTM A 757/A 757M – 04 ASTM A 915/A 915M – 08 ASTM A 958 – 06 FEDERAL QQ-S-681F ISO 3755 ISO 4991 ISO 9477 ISO DIS 13521 ISO WD 14737(c) MIL-C-24707/1 MIL-C-24707/2 MIL-S-870B MIL-S-15083B(NAVY) MIL-S-15464B(SHIPS) MIL-S-23008D(SH) MIL-S-46052A(MR) SAE J435c

Steel Castings Hull Steel Castings Steel Castings for Machinery, Boilers, and Pressure Vessels Steel Castings, Carbon, for General Application Steel Castings, High Strength, for Structural Purposes Steel Castings, Carbon, Suitable for Fusion Welding, for High-Temperature Service Steel Castings, Martensitic Stainless and Alloy, for Pressure-containing Parts, Suitable for HighTemperature Service Steel Castings, Ferritic and Martensitic, for Pressure-Containing Parts, Suitable for Low-Temperature Service Steel Castings, Carbon, Low Alloy and Stainless Steel, Heavy Walled for Steam Turbines Steel Castings, Alloy, Specially Heat-treated, for Pressure-Containing Parts, Suitable for HighTemperature Service Steel Castings, Suitable for Pressure Service Cast Tool Steel Castings, Investment, Carbon and Low Alloy, for General Application, and Cobalt Alloy for High Strength at Elevated Temperatures Steel Castings, Ferritic and Martenistic for Pressure-Containing and Other Applications, for LowTemperature Service Steel Castings, Carbon, and Alloy, Chemical Requirements Similar to Standard Wrought Grades Steel Castings, Carbon, and Alloy, with Tensile Requirements, Chemical Requirements Similar to Standard Wrought Grades Steel Castings Cast carbon steels for general engineering Steel castings for pressure purposes High strength cast steels for general engineering and structural purposes Austenitic manganese steel castings Cast carbon and low alloy steels for general use Castings, Ferrous, for Machinery and Structural Applications Castings, for Pressure Containing Parts Suitable for High Temperature Service Steel Castings, Molybdenum Alloy Steel Castings Steel Alloy, Chromium-Molybdenum; Castings Steel Castings, Alloy, High Yield Strength (HY-80 and HY-100) Steel Castings, High Strength, Low Alloy Automotive Steel Castings

8

AAR M-201-92

STEEL CASTINGS These specifications cover carbon and alloy steel castings for locomotive and car equipment and for miscellaneous use graded as A, B, C, D, and E. AAR Specification M-201 provides for all castings unless another AAR Specification for a particular product provides for a variation.

GRADE & HEAT TREATMENT

MECHANICAL PROPERTIES CHEMICAL COMPOSITION, % (minimum unless range given) (maximum percent unless range given) Tensile Yield Red ABC Grade Elong Other Tests Heat Treatment C Mn P S Si Ni Cr Mo Other Strength Strength A and UNS % Hardness (BHN) ksi MPa Ksi MPa % A Unannealed 60 30 22 30 108 D D 160 0.32 0.90 0.04 0.04 1.50 A A or N 60 30 26 38 108 D D 106 0.32 0.90 0.04 0.04 1.50 B N or NT 70 38 24 36 137 D D 208 0.32 0.90 0.04 0.04 1.50 C NT or QT 90 60 22 45 179 241 0.32 1.85 0.04 0.04 1.50 D QT 105 85 17 35 211 285 0.32 1.85 0.04 0.04 1.50 E QT 120 100 14 30 241 311 0.32 1.85 0.04 0.04 1.50 A Grades D and E steel - composition of the steel, except for coupler locks, shall produce in the standard Jominy test the minimum hardness at 7/16” from the quenched end for the carbon composition as follows, based on the initial composition: up to 0.25% carbon = 30 HRC minimum, 0.25-0.30% carbon = 33 HRC minimum, and 0.31-0.32% carbon = 35 HRC minimum B Impact test - the steel shall possess properties determined by testing standard Charpy V-notch Type “A” specimens prepared as illustrated in Figure 11 in ASTM Designation A 370: grade B 15 ft-lbs @ 20 F, grade C (NT) 15 ft-lbs @ 0 F, grade C (QT) 20 ft-lbs @ -40 F, grade D 20 ft-lbs @ -40 F, and grade E 20 ft-lbs @ -40 F C Dynamic tear and nil ductility test temperature (alternate impact property test): grade B 60 F, grade C (NT) 60 F, grade C (QT) -60 F, grade D -60 F, and grade E -60 F (see original specification for full details) D Grades A and B steel – for each reduction of 0.01% carbon below the maximum specified, an increase of 0.04% manganese above the maximum specified will be permitted to a maximum of 1.2%

ABS 2/1.5

HULL STEEL CASTINGS Requirements cover carbon-steel castings intended to be used in hull construction and equipment as distinguished from hightemperature applications.

GRADE & HEAT TREATMENT Grade and UNS Ordinary

Heat Treatment

MECHANICAL PROPERTIES (minimum unless range given) Tensile Strength ksi

A, N, or NT

MPa

415

Yield Strength Ksi

MPa

205

Elong Red A % %

25

Other Tests

C

40

B

0.23

Mn

P

CHEMICAL COMPOSITION, % (maximum percent unless range given) A,D SPECIFIED RESIDUAL ELEMENTS S Si (maximum percent) Ni Cr Mo Cu Al 0.040 0.60 0.40 0.30 0.15 0.30

0.70 0.040 1.60 Special A, N, or NT 415 205 25 40 Charpy 0.23 0.70 0.035 0.035 0.60 27J (20 ft.lbs)0°C(32°F) 1.60 A Grain refining elements such as aluminum may be used at the discretion of the manufacturer. The content of such elements is to be reported. B For non-welded castings, the maximum carbon content is to be 0.40%. C Aluminum (acid soluable) = 0.015-0.080% D Residual elements - .80% maximum

9

0.020 C 0.10

ABS 2/3.9

Requirements cover carbon-steel castings intended to be used in machinery, boiler and pressure-vessel construction, such as crankshafts, turbine casings and bedplates.

GRADE & HEAT TREATMENT Grade ASTM 1 A27, Grade 60-30 2 A27, Grade 70-36 3 A216, Grade WCA 4 A216, Grade WCB

MECHANICAL PROPERTIES (minimum unless range given) Tensile Strength

Heat Treatment

ksi

A, N, or NT A, N, or NT A, N, or NT A, N, or NT

MPa

Elong Min %

Yield Strength Ksi

MPa

Gauge Length 4d 5d

Red A %

415

205

24

22

35

485

250

22

20

30

415

205

24

22

35

485

250

22

20

35

Other Tests

C

Mn

P

CHEMICAL COMPOSITION, % (maximum percent unless range given) SPECIFIED RESIDUAL ELEMENTS (maximum percent) S Si Ni Cr Mo Cu Al

ASTM A 27/A 27M – 08 STEEL CASTINGS, CARBON, FOR GENERAL APPLICATION This specification covers carbon steel castings for general applications that require up to 70 ksi (485 Mpa) minimum tensile strength. MECHANICAL PROPERTIES (minimum unless range given)

GRADE & HEAT TREATMENT A

Grade and UNS

Tensile Strength

Yield Strength

ksi

ksi

Heat Treatment MPa

MPa

Elong C %

Red A

%

B

Mn

0.25

0.75

0.05

0.06

0.80

0.50

0.50

0.25

0.50

1.00

0.35

0.60

0.05

0.06

0.80

0.50

0.50

0.25

0.50

1.00

0.25

0.75

0.05

0.06

0.80

0.50

0.50

0.25

0.50

1.00

0.30

0.60

0.05

0.06

0.80

0.50

0.50

0.25

0.50

1.00

0.30

0.70

0.05

0.06

0.80

0.50

0.50

0.25

0.50

1.00

0.35

0.70

0.05

0.06

0.80

0.50

0.50

0.25

0.50

1.00

0.25

1.20

0.05

0.06

0.80

0.50

0.50

0.25

0.50

1.00

C

B

CHEMICAL COMPOSITION, % (maximum percent unless range given) SPECIFIED RESIDUAL ELEMENTS (maximum percent) S Si Total Ni Cr Mo Cu E max %

P

N-1 N-2(J03500) A, N, NT, or QT U-60-30 [415-205] (J02500) 60-30 [415-205] (J03000) 65-35 [450-240] (J03001) 70-36 [485-250] (J03501) 70-40 [485-275] D (J02501)

60

415

30

205

22

30

60

415

30

205

24

35

65

450

35

240

24

35

70

485

36

250

22

30

70

485

40

275

22

30

A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT

A

Specify Class 1 or Class 2 `in addition to grade designation (see 9.2) B For each reduction of 0.01% carbon below the maximum specified, an increase of 0.04% manganese above the maximum specified will be permitted to a maximum of 1.40% for grades 70-40 [485-275] and 1.00% for the other grades C When ICI test bars are used in tensile testing as provided for in this specification, the gage length to reduced section diameter ratio shall be 4-1. D Grade 70-40 [485-275] may be used to meet the requirement of Grade 70-36 [485-250] , when agreed upon between the manufacturer and the purchaser. E Total content of residual elements. Supplementary requirement, not required unless stipulated by customer.

10

ASTM A 148/A 148M – 08 STEEL CASTINGS, HIGH STRENGTH, FOR STRUCTURAL PURPOSES

This specification covers carbon steel and alloy steel castings that are to be subjected to higher mechanical stresses than those covered in Specification A 27/A 27M. GRADE & HEAT TREATMENT Grade and UNS 80-40 [550-275] (D50400) 80-50 [550-345] (D50500) 90-60 [620-415] (D50600) 105-85 [725-585] (D50850) 115-95 [795-655] (D50950) 130-115 [895-795] (D51150) 135-125 [930-860] (D51250) 150-135 [1035-930] (D51350) 160-145 [1105-1000] (D51450) 165-150 [1140-1035] (D51500) 165-150L [1140-1035L] (D51501) 210-180 [1450-1240] (D51800) 210-180L B [1450-1240L] (D51801) 260-210 B [1795-1450] (D52100) 260-210L B [1795-1450L] (D52101) A B

MECHANICAL PROPERTIES (minimum unless range given) Yield Strength Elong Red A A ksi MPa % %

Tensile Strength ksi MPa

Heat Treatment 80

550

40

275

18

30

80

550

50

345

22

35

90

620

60

415

20

40

105

725

85

585

17

35

115

795

95

655

14

30

130

895

115

795

11

25

135

930

125

860

9

22

150

1035

135

930

7

18

160

1105

145

1000

6

12

165

1140

150

1035

5

20

165

1140

150

1035

5

20

210

1450

180

1240

4

15

210

1450

180

1240

4

15

260

1795

210

1450

3

6

260

1795

210

1450

3

6

CHEMICAL COMPOSITION, % (maximum percent unless range given) Other Tests A Impact

P

S

A, N, NT, or QT 0.05

0.06

0.05

0.06

0.05

0.06

0.05

0.06

0.05

0.06

0.05

0.06

0.05

0.06

0.05

0.06

0.05

0.06

0.020

0.020

0.020

0.020

0.020

0.020

0.020

0.020

0.020

0.020

0.020

0.020

A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT 20 ft-lb [27 J]

A, N, NT, or QT A, N, NT, or QT 15 ft-lb [20 J]

A, N, NT, or QT

A, N, NT, or QT 6 ft-lb [8 J]

A, N, NT, or QT

When ICI test bars are used in tensile testing as provided for in this specification, the gage length to reduced section diameter ratio shall be 4-1. These grades must be charpy tested as prescribed in Section 9, and with minimum values as shown in Table 3.

11

ASTM A 216/A 216M – 07

STEEL CASTINGS, CARBON, SUITABLE FOR FUSION WELDING, FOR HIGH TEMPERATURE SERVICE This specification covers carbon steel castings for valves, flanges, fittings, or other pressure-containing parts for high-temperature service and of quality suitable for assembly with other castings or wrought-steel parts by fusion welding.


Grade and UNS

MECHANICAL PROPERTIES (minimum unless range given)

Heat Treatment

Tensile Strength

A

ksi

Yield Strength

MPa

Ksi

F

Mpa

CHEMICAL COMPOSITION, % (maximum percent unless range given)

Elong %

Red A %

C

Mn

G

P

S

SPECIFIED RESIDUAL ELEMENTS E (maximum percent)

Si Ni

Cr

Mo

Cu

V

Total Content max %

WCA 60 415 30 205 24 35 A, N, NT B B J02502 85 585 0.25 0.70 0.04 0.045 0.60 0.50 0.50 0.20 0.30 0.03 1.00 WCB 70 485 36 250 22 35 A, N, NT C C J03002 95 655 0.30 1.00 0.04 0.045 0.60 0.50 0.50 0.20 0.30 0.03 1.00 WCC 70 485 40 275 22 35 A, N, NT D D J02503 95 655 0.25 1.20 0.04 0.045 0.60 0.50 0.50 0.20 0.30 0.03 1.00 A Quench and temper may only be applied if supplemental requirement S15 is specified B For each reduction of 0.01% below the specified maximum carbon content, an increase of 0.04% manganese above the specified maximum will be permitted up to a maximum of 1.10% C For each reduction of 0.01% below the specified maximum carbon content, an increase of 0.04% manganese above the specified maximum will be permitted up to a maximum of 1.28% D For each reduction of 0.01% below the specified maximum carbon content, an increase of 0.04% manganese above the specified maximum will be permitted up to a maximum of 1.40% E Not applicable when Supplementary Requirement S11 is specified F Determine by either 0.2% offset method or 0.55 extension-under-load method. G When ICI test bars are used in tensile testing as provided for in Specification A 703/A 703M, the gage length to reduced section diameter ratio shall be 4-1.

ASTM A 217/A 217M – 07

STEEL CASTINGS, MARTENSITIC STAINLESS AND ALLOY, FOR PRESSURE-CONTAINING PARTS, SUITABLE FOR HIGHTEMPERATURE SERVICE This specification covers martensitic stainless steel and alloy steel castings for values, flanges, fittings, and other pressurecontaining parts intended primarily for high-temperature and corrosive service.

GRADE & HEAT TREATMENT Grade and UNS WC1 J12524 WC4 J12082 WC5 J22000 WC6 J12072 WC9 J21890

Heat Treatment

NT NT NT NT NT

MECHANICAL PROPERTIES (minimum unless range given) Yield Tensile Strength Elong A Strength ksi 65 90 70 95 70 95 70 95 70 95

MPa 450 620 485 655 485 655 485 655 485 655

ksi 35

MPa 240

% 24

Red A

B

%

C

Mn

0.25 0.05 0.20 0.05 0.20 0.05 0.20 0.05 0.18

0.50 0.80 0.50 0.80 0.40 0.70 0.50 0.80 0.40 0.70

35

40

275

20

35

40

275

20

35

40

275

20

35

40

275

20

35

P

S

Si

Ni

0.04 0.045 0.60 0.70 0.04 0.045 0.60 1.10 0.60 0.04 0.045 0.60 1.00 0.04 0.045 0.60 0.04 0.045 0.60

12

CHEMICAL COMPOSITION, % (maximum percent unless range given) SPECIFIED RESIDUAL ELEMENTS (maximum percent) Total Cr Mo Cb N V Al Cu Ni Cr Ti W V Zr Content max. 0.45 0.65 0.50 0.50 0.35 0.10 1.00 0.50 0.45 0.80 0.65 0.50 0.10 0.60 0.50 0.90 0.90 1.20 0.50 0.10 0.60 1.00 0.45 1.50 0.65 0.50 0.50 0.10 1.00 2.00 0.90 2.75 1.20 0.50 0.50 0.10 1.00

GRADE & HEAT TREATMENT Grade and UNS WC11 J11872 C5 J42045 C12 J82090 C12A J84090

NT NT NT NT

CA15 J91156 A B

Heat Treatment

NT

MECHANICAL PROPERTIES (minimum unless range given) Yield Tensile Strength Elong A Strength ksi

MPa

ksi

MPa

%

Red A

B

%

80 105 90 115 90 115 85 110

550 725 620 795 620 795 585 760

50

345

18

45

60

415

18

35

60

415

18

35

60

415

18

45

90 115

620 795

65

450

18

30

CHEMICAL COMPOSITION, % (maximum percent unless range given) SPECIFIED RESIDUAL ELEMENTS (maximum percent) Total C Mn P S Si Ni Cr Mo Cb N V Al Cu Ni Cr Ti W V Zr Content max. 0.15 0.50 0.30 1.00 0.45 0.21 0.80 0.020 0.015 0.60 1.50 0.65 0.01 0.35 0.50 0.03 1.00 0.40 4.00 0.45 0.20 0.70 0.04 0.045 0.75 6.50 0.65 0.50 0.50 0.10 1.00 0.35 8.00 0.90 0.20 0.65 0.04 0.045 1.00 10.00 1.20 0.50 0.50 0.10 1.00 0.08 0.30 0.20 8.0 0.85 0.060 0.030 0.18 0.12 0.60 0.030 0.010 0.50 0.40 9.5 1.05 0.10 0.070 0.25 0.02 0.01 0.01 11.5 0.15 1.00 0.040 0.040 1.50 1.00 14.0 0.50

Determine by either 0.2% offset method or 0.5% extension-under-load method. When ICI test bars are used in tensile testing as provided for in Specification A 703/A 703M, the gage length to reduced section diameter ratio shall be 4-1.

ASTM A 352/A 352M – 06

STEEL CASTINGS, FERRITIC AND MARTENSITIC, FOR PRESSURE-CONTAINING PARTS, SUITABLE FOR LOWTEMPERATURE SERVICE This specification covers steel castings for valves, flanges, fittings, and other pressure-containing parts intended primarily for lowtemperature service.

GRADE & HEAT TREATMENT Grade

Heat Treatment

and UNS LCA J02504 A LCB J03003 LCC J02505 LC1 J12522 LC2 J22500 LC2-1 J42215 LC3 J31550 LC4 J41500 LC9 J31300 CA6NM J91540

Tensile C Strength ksi

NT or QT NT or QT NT or QT NT or QT NT or QT NT or QT NT or QT NT or QT QT NT

MPa

MECHANICAL PROPERTIES (minimum unless range given) Yield Elong Red. C,F Impact Tests D E Strength Area ksi

MPa

%

%

60 85 65 90 70 95 65 90 70 95 105 130 70 95 70 95 85

415 585 450 620 485 655 450 620 485 655 725 895 485 655 485 655 585

30

205

24

35

35

240

24

35

40

275

22

35

35

240

24

35

40

275

24

35

110 135

760 930

80

550

18

30

40

275

24

35

40

275

24

35

75

515

20

30

80

550

15

35

Average 13(-25) [18(-32)] 13(-50) [18(-46)] 15(-50) [20(-46)] 13(-75) [18(-59)] 15(-100) [20(-73)] 30(-100) [41(-73)] 15(-150) [20(-101)] 15(-175) [20(-115)] 20(-320) [27(-196)] 20(-100) [27(-73)]

A

Single

CHEMICAL COMPOSITION, % (maximum percent unless range given) SPECIFIED RESIDUAL ELEMENTS B (maximum percent) C

10[14] 0.25

Si

A

Mn

0.60 0.70

P

A

S

Ni

Cr

0.04 0.045

Mo

Cu

0.20

0.30

V

Ni

Cr

0.50 0.50

Mo

Cu

V

Total Content Max

0.03 1.00

10[14] 0.30 10[16] 0.25

0.60 1.00 A

0.15

0.60 1.20 0.50 0.60 0.80 0.50 0.60 0.80 0.55 0.50 0.75 0.50 0.60 0.80 0.50 0.60 0.80

0.13

0.45 0.90

0.06

1.00 1.00

10[14] 0.25 12[16] 0.25 25[34] 0.22 12[16] 0.15 12[16] 15[20] 15[20]

13

0.04 0.045 A

0.50 0.50 0.20 0.30 0.03 1.00

0.04 0.045

0.50 0.50 0.20 0.30 0.03 1.00 0.45 0.65

0.04 0.045 2.00 0.04 0.045 3.00 2.50 0.04 0.045 3.50 3.00 0.04 0.045 4.00 4.00 0.04 0.045 5.00 8.50 0.04 0.045 10.0 3.5 0.04 0.03 4.5

1.35 1.85

0.30 0.60

0.50 11.5 14.0

0.20 0.4 1.0

0.30

0.03

A

B C D E F

For each reduction of 0.01% carbon below the maximum specified, an increase of 0.04% manganese above the maximum specified will be permitted up to a maximum of 1.10% for LCA), 1.28%doe LCB), and 1.40% for LCC). Specified Residual Elements-The total content of these elements is 1.00% maximum. See 1.2 Determine by either 0.2% offset method or 0.5% extension-under-load method. When ICI test bars are used in tensile testing as provided for in Specification A 703/A 703M, the gage length to reduced section diameter ratio shall be 4-1. See Appendix X1

ASTM A 356/A 356M – 07

STEEL CASTINGS, CARBON, LOW ALLOY AND STAINLESS STEEL, HEAVY WALLED FOR STEAM TURBINES This specification covers one grade of martensitic stainless steel and several grades of ferritic steel castings for cylinders (shells), value chests, throttle valves, and other heavy-walled castings for steam turbine applications.

Grade and UNS 1 J03502 2 J12523 5 J12540 6 J12073 8 J12073 9 J21610 10 J22090 C 12A J80490 CA6NM J91540 A B C

Heat Treatment NT NT NT NT NT NT NT NT NT

A

MECHANICAL PROPERTIES (minimum unless range given)


Tensile Strength Ksi MPa 70 485 65 70 70

450 485 485

Yield Strength Ksi MPa 36 250 35 40 45

240 275 310


Elong Red A % % 20 35 22 22 22

C

550

50

345

18

585

60

415

15

85 110

585 585 760

55 60 80

380 415 550

20 20

B

0.60 0.035

0.030

0.25

B

0.70

B

0.60 0.035

0.030

0.25

B

B

0.60 0.035

0.030

0.60 0.035 0.20 0.60 0.035 0.20 0.60 0.035

0.030

0.20 0.08 0.12

0.70 0.50 0.80 0.50 0.90 0.50 0.90 0.50 0.80 0.30 0.60

0.60 0.035 0.20 0.50 0.30

0.030

0.06

1.00

1.00 0.040

0.030

35 35 35 45 45

15

35 .....

S

0.70

0.20 85

P

B

0.20 85

Si

0.35

0.20 80

Mn

0.030 0.030

0.010

35

Mo

Cr

Ni

V

Cb

N

Al

Zr

.....

.....

.....

.....

.....

.....

.....

.....

.....

0.45 0.65 0.40 0.60 0.45 0.65 0.90 1.20 0.90 1.20 0.90 1.20 0.85 1.05 0.4 1.0

.....

.....

.....

.....

.....

.....

.....

.....

0.40 0.70 1.00 1.50 1.00 1.50 1.00 1.50 2.00 2.75 8.0 9.5 11.5 14.0

.....

.....

.....

.....

.....

.....

.....

.....

.....

.....

.....

.....

.....

.....

.....

0.05 ..... 0.15 0.20 ..... 0.35 ..... .....

.....

.....

.....

.....

.....

.....

.....

.....

.....

.....

.....

.....

0.030 0.070 .....

0.02 0.01 0.01 ..... ..... .....

..... .....

0.18 0.060 0.40 0.25 0.10 3.5 ..... ..... 4.5

Where ellipses appear in this table, there is no requirement. For each 0.01% reduction in carbon below the maximum specified, an increase of 0.04% points of manganese over the maximum specified for that element may be permitted up to 1.00% The designation of Grade 12, formerly covered by this specification has been changed to Grade 12A.

14

Ti

ASTM A 389/A 389M – 08

STEEL CASTINGS, ALLOY, SPECIALLY HEAT-TREATED, FOR PRESSURE-CONTAINING PARTS, SUITABLE FOR HIGHTEMPERATURE SERVICE This specification covers alloy steel castings, which have been subjected to special heat treatment, for valves, flanges, fittings, and other pressure-containing parts intended primarily for high-temperature service. MECHANICAL PROPERTIES (minimum unless range given) Tensile Strength Yield Strength A

GRADE & HEAT TREATMENT Grade and UNS

Heat Treatment

C23 J12080 C24 J12092 A

ksi

NT

MPa

Ksi

CHEMICAL COMPOSITION, % (maximum percent unless range given) Elong

MPa

%

Red A %

B

70

483

40

276

18

35

80

552

50

345

15

35

C 0.20

NT

0.20

Mn 0.30 0.80 0.30 0.80

P

S

Si

0.04

0.045

0.60

0.04

0.045

0.60

Cr

Mo

1.00 1.50 0.80 1.25

0.45 0.65 0.90 1.20

V 0.15 0.25 0.15 0.25

Determine by either 0.2% offset method or 0.5% extension-under-load method. When ICI test bars are used in tensile testing as provided for in Specification A 703/A 703M, the gage length to reduced section diameter ratio shall be 4-1.

B

ASTM A 487/A 487M – 07

STEEL CASTINGS, SUITABLE FOR PRESSURE SERVICE This specification covers low-alloy steels, and martenistic stainless steels in the normalized and tempered, or quenched and tempered condition suitable for pressure-containing parts. The weldability of the classes in the specification varies from readily weldable to weldable only with adequate precautions, and the weldability of each class should be considered prior to assembly by fusion welding.

MECHANICAL PROPERTIES (min. unless range given)

GRADE Tensile H Strength Grade

Class Ksi

1 J13002

A B

J

585 760 620 795 620

55

85 110 90 115 90

380

22

65

450

22

45

585 760 620 795 620

53

365

22

35

65

450

22

40

65

450

22

40

620 795 725 895 620

60

415

18

40

C

90 115 105 130 90

D

100

690

E

115

A

115

A

A

Hardness (max) HRC (BHN)

Thickness (max) in [mm]

C

Mn

P

S

Si

Ni

Cr

Mo

40 45

B

7 J12084

85 110 90 115 90

Mpa

22

C

6 J13855

ksi

Red Area %

450

B

4 J13047

Mpa

SPECIFIED RESIDUAL ELEMENTS (maximum percent) Elong %

65

C 2 J13005

Yield Strength

CHEMICAL COMPOSITION, % (max. percent unless range given)

17

35

60

415

18

35

22 (235)

75

515

17

35

22 (235)

795

95

655

15

35

795

80

550

18

30

825

95

655

12

25

A

115

795

100

690

15

30

Cu

0.04 0.12

0.30

1.00

0.04

0.045

0.80

0.30

1.00 1.40

0.04

0.045

0.80

0.30

1.00

0.04

0.045

0.80

0.40 0.80

0.05 0.38

1.30 1.70

0.04

0.045

0.80

0.05 0.20

0.60 1.00

0.04

0.045

0.80

Cu

Ni

Cr

0.50

0.50

0.35

0.10 0.30

0.50

0.50

0.35

0.40 0.80

0.15 0.30

0.40 0.80

0.40 0.80

0.30 0.40

0.70 1.00

0.40 0.80

0.40 0.60

Mo

Mo+W

W

V

0.25

Total Content 1.00

0.10

0.03

1.00

0.50

0.10

0.03

0.60

0.50

0.10

0.03

0.60

0.50

0.10

22 (235)

585

120

B

22 (235)

85

B

V

2.5 [63.5]

15

0.03 0.10

0.002 0.006

0.15 0.50

0.60

MECHANICAL PROPERTIES (min. unless range given)

GRADE Tensile H Strength Grade

Class Ksi

8 J22091

Yield Strength

A

Mpa

ksi

B

85 110 105

585 760 725

55 85

C

100

690

A

90

620

60

B

105

725

C

90

D

100

E A

Mpa

CHEMICAL COMPOSITION, % (max. percent unless range given) SPECIFIED RESIDUAL ELEMENTS (maximum percent)

Elong %

Red Area %

Hardness (max) HRC (BHN)

380

20

35

585

17

30

515

17

35

415

18

35

85

585

16

35

620

60

415

18

35

22 (235)

690

75

515

17

35

22 (235)

115

795

95

655

15

35

100

690

70

485

18

35

Thickness (max) in [mm]

C

Mn

P

S

Si

Ni

Cr

Mo

V

B

Cu

Cu

0.05 0.20

0.50 0.90

0.04

0.045

0.80

2.00 2.75

0.90 1.10

0.50

0.05 0.33

0.60 1.00

0.04

0.045

0.80

0.75 1.10

0.15 0.30

0.50

0.30

0.60 1.00

0.04

0.045

0.80

1.40 2.00

0.55 0.90

0.20 0.40

0.05 0.20

0.50 0.80

0.04

0.045

0.60

0.70 1.10

0.50 0.80

0.05 0.20

0.40 0.70

0.04

0.045

0.60

0.60 1.00

0.50 0.90

0.30

0.80 1.10

0.04

0.045

0.60

0.55

0.80 1.10

0.04

0.045

0.60

0.02

0.02

Ni

Cr

Mo

Mo+W

W

V

Total Content

0.10

0.03

0.60

0.10

0.03

1.00

0.50

0.10

0.03

0.60

0.45 0.65

0.50

0.10

0.03

0.50

0.90 1.20

0.50

0.10

0.03

0.50

1.40 1.75

0.20 0.30

0.50

0.40

0.10

0.03

0.75

0.20 0.30

0.50

0.40

0.10

0.03

0.75

0.50

1.40 1.75 1.00 1.40

0.20

0.20

0.10

0.02

0.50

0.50

0.10

0.05

0.50

0.50

0.10

0.05

0.50

0.50

0.10

0.05

0.50

75 9 J13345

10 J23015 11 J12082

B

125

860

100

690

15

35

A

484 655 725 895 485 655 725 895 620 795 725 895 825 1000 485 655 965 1170 620 795 620

40

275

20

35

C

70 95 105 130 70 95 105 130 90 115 105 130 120 145 70 95 140 170 90 115 90

D

100

690

A

90 115 110 135 100

620 795 760 930 690

B 12 J22000

A B

13 J13080

A B

14 J15580 16 J31200 CA15 J91171

A A A B

CA15M J91151 CA6NM J91540

A B

85

585

17

35

40

275

20

35

85

585

17

35

60

415

18

35

85

585

17

35

95

655

14

30

40

275

22

35

22 (235)

0.12 110 130 65

760 895 450

10 18

30

60

415

18

35

22 (235)

75

515

17

35

22 (235)

65

450

18

30

80

550

15

35

75

515

17

35

K

2.10

K

25

23 (255)

I

0.15

1.00

0.040

0.040

1.50

1.00

11.5 14.0

0.50

0.15

1.00

0.040

0.040

0.65

0.06

1.00

0.04

0.03

1.00

1.0 3.5 4.5

11.5 14.0 11.5 14.0

0.15 1.0 0.4 1.0

A

0.50

0.10

A = air, L = liquid Minimum temperature unless range is specified Double austenitize D Double temper with the final temper at a lower temperature than the intermediate temper E Air cool to below 200F [95C] after first temper F Intermediate G Final H Minimum ksi, unless range is given I Test methods and definitions A 370, Table 3a does not apply to CA6NM – the conversion given is based on CA6NM test coupons (for example, see ASTM STP 756) J Proprietary steel composition K For each reduction of 0.01% below the specified maximum carbon content, an increase of 0.40% manganese above the specified maximum will be permitted up to a maximum of 2.30% B C

16

ASTM A 597 – 99

CAST TOOL STEEL This specification covers tool steel compositions for usable shapes cast by pouring directly into suitable molds and for master heats for remelting and casting.

GRADE


Grade and UNS

C

CA-2 T90102 CD-2 T90402 CD-5 T90405 CS-5 T91905 CM-2 T11302 CS-7 T41907 CH-12 T90812 CH-13 T90813 CO-1 T91501 A

0.95 1.05 1.40 1.60 1.35 1.60 0.50 0.65 0.78 0.88 0.45 0.55 0.30 0.40 0.30 0.42 0.85 1.00

Mn

P

S

Si

0.75

0.03

0.03

1.50

1.00

0.03

0.03

1.50

0.75 0.60 1.00

0.03

0.03

0.03

0.03

1.50 1.75 2.25

0.75 0.40 0.80

0.03

0.03

0.03

0.03

1.00 0.60 1.00

0.75

0.03

0.03

1.50

0.75 1.00 3.00

0.03

0.03

1.50

0.03

0.03

1.50

Ni

Cr

Mo

4.75 5.50 11.00 13.00 11.00 13.00

0.40 A 0.60

0.90 1.40 0.70 1.20 0.70 1.20 0.20 0.80 4.50 5.50 1.20 1.60 1.25 1.75 1.25 1.75

0.35 3.75 4.50 3.00 3.50 4.75 5.75 4.75 5.75 0.40 1.00

0.25

V

Co

0.20 A 0.50 0.04 A 1.00 0.35 0.55

0.70 A 1.00 2.50 3.50

0.35 1.25 2.20

.25

0.20 0.50 0.75 1.20

W

5.50 6.75 1.00 1.70 0.40 0.60

0.30

Optional element – tool steels have found satisfactory application, either with or without the element present; if desired they should be specified with order

ASTM A 732/A 732M – 05

CASTINGS, INVESTMENT, CARBON AND LOW ALLOY, FOR GENERAL APPLICATION, AND COBALT ALLOY FOR HIGH STRENGTH AT ELEVATED TEMPERATURES This specification covers carbon and low-alloy steel castings made by the investment casting process.


Grade and UNS 1A J02002 2A J03011 2Q J03011 3A J04002

Heat Treatment A

C

A QT A

D


MPa

Yield Strength Ksi

MPa

Elong %

60

414

40

276

24

65

448

45

310

25

85

586

60

414

10

75

517

48

331

25

Red A %

Other Tests Stress B Rupture


C 0.15 0.25 0.25 0.35 0.25 0.35 0.35 0.45

Mn 0.20 0.60 0.70 1.00 0.70 1.00 0.70 1.00

P

S

Si

0.20 0.04 0.045 1.00 0.20 0.04 0.045 1.00 0.20 0.04 0.045 1.00 0.20 0.04 0.045 1.00

17

Ni

Cr

Mo

V

Co

W

Fe

B

SPECIFIED RESIDUAL ELEMENTS (maximum percent) Mo+ Total Cu Ni Cr W W Content 0.50 0.50 0.35 0.25 1.00 0.50

0.50

0.35

0.10

1.00

0.50

0.50

0.35

0.10

1.00

0.50

0.50

0.35

0.10

1.00


Grade and UNS 3Q J04002 4A 4Q 5N J13052 6N J13512 7Q J13045 8Q J14049 9Q J23055 10Q J24054 11Q J12094 12Q J15048 13Q J12048 14Q J13051 F 15A J19966 21 31

Heat Treatment QT A QT NT

E

NT QT QT QT QT QT QT QT QT


MPa

Yield Strength Ksi

MPa

Elong %

100

689

90

621

10

90

621

50

345

20

125

862

100

689

5

85

586

55

379

22

As cast

Other Tests Stress B Rupture

C 0.35 0.45 0.45 0.55 0.45 0.55 0.30

90

621

60

414

20

150

1030

115

793

7

180

1241

145

1000 5

150

1030

115

793

180

1241

145

1000 5

120

827

100

689

190

1310

170

1172 4

105

724

85

586

10

150

1030

115

793

7

7

10

360

A

10

HRB 100 max. 23.0 [160]

380

A

10

30.0 [205]

A As cast

Red A %


52

A

55

A

Mn 0.70 1.00 0.70 1.00 0.70 1.00 0.70 1.00 1.35 1.75 0.40 0.70 0.70 1.00 0.40 0.70 0.70 1.00 0.40 0.70 0.65 0.95 0.65 0.95 0.65 0.95 0.25 0.55

0.35 0.25 0.35 0.35 0.45 0.25 0.35 0.35 0.45 0.15 0.25 0.45 0.55 0.15 0.25 0.25 0.35 0.95 1.10 0.20 0.30 1.00 0.45 0.55 1.00

P

S

Si

0.20 0.04 0.045 1.00 0.20 0.04 0.045 1.00 0.20 0.04 0.045 1.00 0.20 0.04 0.045 0.80 0.20 0.04 0.045 0.80 0.20 0.04 0.045 0.80 0.20 0.04 0.045 0.80 0.20 0.04 0.045 0.80 0.20 0.04 0.045 0.80 0.20 0.04 0.045 0.80 0.20 0.04 0.045 0.80 0.20 0.04 0.045 0.80 0.20 0.04 0.045 0.80 0.20 0.04 0.045 0.80

Ni

Mo

V

Co

18

Fe

B

1.65 2.00 1.65 2.00 1.65 2.00 0.40 0.70 0.40 0.70

0.80 1.10 0.80 1.10 0.70 0.90 0.70 0.90 0.80 1.10 0.40 0.70 0.40 0.70 1.30 1.60 25 29 24.5 26.5

0.25 0.55 0.15 0.25 0.15 0.25 0.20 0.30 0.20 0.30 0.20 0.30

0.50

0.10

0.60

0.50

0.10

0.60

0.50

0.50

0.35 0.25

0.50

0.50

0.35

0.50 0.50

0.50

0.10

0.60

0.50

0.10

1.00

0.10

0.60

0.10

1.00

0.10

1.00

0.35

0.50 0.50

0.15 0.25 0.15 0.25 remainder

3.00 0.007

remainder 7.0 2.00 0.005 8.0 0.015

0.50

0.10

1.00

0.50

0.10

1.00

0.50

0.10

0.60

0.10

0.60

0.50 5 6

1.00

0.50

0.15

1.00 0.25

0.50

Test at elevated temperature, 1500F [820C] Stress rupture test at 1500F [820C], stress units in ksi [MPa], the minimum rupture life is 15 hours with a minimum elongation in 4D of 5% C Annealed. D Quenched and tempered. E Normalized and tempered F Hardness Rockwell B, 100Max. B

W

0.05 0.15

1.7 0.040 0.040 1.00 3.8 9.5 0.040 0.040 1.00 11.5

A

Cr

SPECIFIED RESIDUAL ELEMENTS (maximum percent) Mo+ Total Cu Ni Cr W W Content 0.50 0.50 0.35 0.10 1.00

0.50

ASTM A 757/A 757M – 04

STEEL CASTINGS, FERRITIC AND MARTENISTIC FOR PRESSURE-CONTAINING AND OTHER APPLICATIONS, FOR LOWTEMPERATURE SERVICE This specification covers carbon and low-alloy steel castings for pressure-containing and other applications intended primarily for petroleum and gas pipelines in areas subject to low-ambient temperatures. Castings shall be heat treated by normalizing and tempering or liquid quenching and tempering. All classes are weldable under proper conditions. Hardenability of some grades may limit useable section size.

GRADE & HEAT TREATMENT Grade And UNS A1Q J03002 A2Q J02503 B2N, B2Q J22501 B3N, B3Q J31500 B4N, B4Q J41501 C1Q J12582 D1N1, D1Q1 J22092 D1N2, D1Q2 J22092 D1N3, D1Q3 J22092 E1Q J42220 E2N1, E2Q1 E2N2, E2Q2 E2N3, E2Q3 E3N J91550


Yield Strength Elong %

Heat Treatment Ksi

QT QT NT or QT NT or QT NT or QT QT 1100F NT or QT NT or QT NT or QT QT 1100F NT or QT NT or QT NT QT NT

MPa

Ksi

MPa

Red A %


Other Tests Impact

SPECIFIED RESIDUAL ELEMENTS Maximum %

A

C

B

65

450

35

240

24

35

13(-50) [17(-46)]

70

485

40

275

22

35

15(-50) [20(-46)]

70

485

40

275

24

35

15(-100) [20(-73)]

70

485

40

275

24

35

15(-150) [20(-101)]

70

485

40

275

24

35

15(-175) [20(-115)]

75

515

55

380

22

35

15(-50) [20(-46)]

85 115 95 125 105 135 90

585 795 655 860 725 930 620

55

380

20

35

C

75

515

18

35

C

85

585

15

30

C

65

450

22

40

30(-100) [41(-73)]

90 120 105 135 115 145 110

620 825 725 930 795 1000 760

70

485

18

35

30(-100) [41(-73)]

85

585

15

30

20(-100) [27(-73)]

100

690

13

30

15(-100) [20(-73)]

80

550

15

35

20(-100) [27(-73)]

Mn

P

S

Si

Ni

Cr

Mo V

0.30 0.25 0.25 0.15 0.15 0.25

1.00 D

1.20 0.50 0.80 0.50 0.80 0.50 0.80

D

0.025 0.25

0.60

0.025 0.25

0.60

0.025 0.25

0.60

0.025 0.25

0.60

0.025 0.25

0.60

0.025 0.25

0.20

1.20 0.40 0.80 0.40 0.80 0.40 0.80 0.50 0.80 0.40 0.70 0.40 0.70 0.40 0.70

0.06

1.00

0.030 0.030 1.00

0.20 0.20 0.20 0.22 0.20 0.20

A

0.60

0.025 0.25

0.60

0.025 0.25

0.60

0.025 0.25

0.60

0.025 0.25

0.60

0.020 0.020 0.60 0.020 0.020 0.60 0.020 0.020 0.60

2.0 3.0 3.0 4.0 4.0 5.0 1.5 2.0

2.5 3.5 2.75 3.90 2.75 3.90 2.75 3.90 3.5 4.5

2.0 2.75 2.0 2.75 2.0 2.75 1.35 1.85 1.50 2.0 1.50 2.0 1.50 2.0 11.5 14.0

Refer to the original specification for additional information on toughness requirements and effective section size information See original specification for full details – units are in ft-lbs @ (F) and [J @ (C)] C Requirements shall be subject to agreements between the manufacturer and the purchaser D For each 0.01% carbon below the maximum specified, an increase of 0.04% manganese over the maximum specified will be permitted up to 1.40% E Total residuals includes phosphorus and sulfur. B

19

0.15 0.30 0.90 1.20 0.90 1.20 0.90 1.20 0.35 0.60 0.40 0.60 0.40 0.60 0.40 0.60 0.40 1.0

Cu

Ni

Cr

Mo

Total W Content E %

0.30 0.50 0.50 0.40 0.25

1.00

0.30 0.50 0.50 0.40 0.25

1.00

0.30 0.50

0.40 0.25

1.00

0.30 0.50

0.40 0.25

1.00

0.30 0.50

0.40 0.25

1.00

0.30 0.50

0.40

1.00

0.03 0.50 0.50

0.10 1.00

0.03 0.50 0.50

0.10 1.00

0.03 0.50 0.50

0.10 1.00

0.03 0.50

0.70

0.30 0.50

0.10 0.70

0.30 0.50

0.10 0.70

0.30 0.50

0.10 0.70

0.50

0.10 0.50

ASTM A 915/A 915M – 08

STEEL CASTINGS, CARBON, AND ALLOY, CHEMICAL REQUIREMENTS SIMILAR TO STANDARD WROUGHT GRADES This specification covers carbon and low-alloy steel castings having chemical analyses similar to that of the standard wrought grades. GRADE & HEAT TREATMENT

Grade and UNS SC 1020 J02003 SC 1025 J02508 SC 1030 J03012 SC 1040 J04003 SC 1045 J04502 SC 4130 J13502 SC 4140 J14045 SC 4330 J23259 SC 4340 J24053 SC 8620 J12095 SC 8625 J12595 SC 8630 J13095


Heat Treatment As cast, A, N, NT, or QT As cast, A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT

C 0.18 0.23 0.22 0.28 0.28 0.34 0.37 0.44 0.43 0.50 0.28 0.33 0.38 0.43 0.28 0.33 0.38 0.43 0.18 0.23 0.23 0.28 0.28 0.33

Mn 0.40 0.80 0.40 0.80 0.50 0.90 0.50 0.90 0.50 0.90 0.40 0.80 0.70 1.10 0.60 0.90 0.60 0.90 0.60 1.00 0.60 1.00 0.60 1.00

20

P

S

0.040

0.040

0.040

0.040

0.040

0.040

0.040

0.040

0.040

0.040

0.035

0.040

0.035

0.040

0.035

0.040

0.035

0.040

0.035

0.040

0.035

0.040

0.035

0.040

Si 0.30 0.60 0.30 0.60 0.30 0.60 0.30 0.60 0.30 0.60 0.30 0.60 0.30 0.60 0.30 0.60 0.30 0.60 0.30 0.60 0.30 0.60 0.30 0.60

Ni

1.65 2.00 1.65 2.00 0.40 0.70 0.40 0.70 0.40 0.70

Cr

0.80 1.10 0.80 1.10 0.70 0.90 0.70 0.90 0.40 0.60 0.40 0.60 0.40 0.60

Mo

0.15 0.25 0.15 0.25 0.20 0.30 0.20 0.30 0.15 0.25 0.15 0.25 0.15 0.25

ASTM A 958 – 06

STEEL CASTINGS, CARBON, AND ALLOY, WITH TENSILE REQUIREMENTS, CHEMICAL REQUIREMENTS SIMILAR TO STANDARD WROUGHT GRADES This specification covers carbon and low-alloy steel castings having chemical analyses similar to that of the standard wrought grades.

GRADE & HEAT TREATMENT Grade and UNS SC 1020 J02003 SC 1025 J02508 SC 1030 J03012 SC 1040 J04003 SC 1045 J04502 SC 4130 J13502 SC 4140 J14045 SC 4330 J23259 SC 4340 J24053 SC 8620 J12095 SC 8625 J12595 SC 8630 J13095

Heat Treatment A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT A, N, NT, or QT

MECHANICAL PROPERTIES (minimum unless range given) AC Tensile Requirements/Grade Suitability 65/35

X

A

70/36

80/40

80/50

90/60

105/85

115/96

130/115

135/125

150/135

CHEMICAL COMPOSITION, % (maximum percent unless range given) 160/145

165/150

210/180

X

X

X

X

X

X

X

X

X

X

X

B

X

X

B

X

B

X

X

X

X

X

X

B

XB

X

X

X

X

X

X

X

X

X

B

X

B

X

B

X

B

X

X

X

X

X

X

X

X

X

B

X

B

X

B

X

B

X

X

X

X

X

X

X

X

X

X

B

X

B

X

B

X

B

X

X

X

X

X

X

X

X

X

B

X

B

X

X

X

X

X

X

B

X

B

X

X

X

X

X

X

X

X

B

X

B

X

X

X

X

X

X

X

X

B

X

C

Mn

0.18 0.23 0.22 0.28 0.28 0.34 0.37 0.44 0.43 0.50 0.28 0.33 0.38 0.43 0.28 0.33 0.38 0.43 0.18 0.23 0.23 0.28 0.28 0.33

0.40 0.80 0.40 0.80 0.50 0.90 0.50 0.90 0.50 0.90 0.40 0.80 0.70 1.10 0.60 0.90 0.60 0.90 0.60 1.00 0.60 1.00 0.60 1.00

P

S

Si

0.30 0.040 0.040 0.60 0.30 0.040 0.040 0.60 0.30 0.040 0.040 0.60 0.30 0.040 0.040 0.60 0.30 0.040 0.040 0.60 0.30 0.035 0.040 0.60 0.30 0.035 0.040 0.60 0.30 0.035 0.040 0.60 0.30 0.035 0.040 0.60 0.30 0.035 0.040 0.60 0.30 0.035 0.040 0.60 0.30 0.035 0.040 0.60

Ni

Cr

Mo

1.65 2.00 1.65 2.00 0.40 0.70 0.40 0.70 0.40 0.70

0.80 1.10 0.80 1.10 0.70 0.90 0.70 0.90 0.40 0.60 0.40 0.60 0.40 0.60

0.15 0.25 0.15 0.25 0.20 0.30 0.20 0.30 0.15 0.25 0.15 0.25 0.15 0.25

A

X denotes that the properties may be achieved by at least one of the heat treatments referenced in 5. The effect of section thickness should be considered in making greade selections. The heat treatment requirements do not imply that all section thicknesses will be through hardened. B These grades are likely to significantly exceed the minimum strength levels; therefore, problems may be experienced when trying to produce castings to low hardness values C Tensile requirements for the different classes given in the table below TENSILE REQUIREMENTS Class 65/35 Tensile (ksi) 65 Tensile [MPa] 450 Yield (ksi) 35 Yield [MPa] 240 Elong. (%) 24 Red. A (%) 35

70/36 70 485 36 250 22 30

FEDERAL QQ-S-681F

STEEL CASTINGS

80/40 80 550 40 275 18 30

80/50 80 550 50 345 22 35

90/60 90 620 60 415 18 35

105/85 105 725 85 585 17 35

115/95 115 795 95 655 14 30

130/115 130 895 115 795 11 25

135/125 135 930 125 860 9 22

150/135 150 1035 135 930 7 18

160/145 160 1105 145 1000 6 12

165/150 165 1140 150 1035 5 10

210/180 210 1450 180 1240 4 8

This specification covers mild-to-medium-strength carbon steel castings for general application as described in ASTM A 27 and high-strength steel castings for structural purposes as described in ASTM A 148. Canceled May 20, 1985 – use ASTM A 27 and ASTM A 148

21

ISO 3755

CAST CARBON STEELS FOR GENERAL ENGINEERING This International Standard specifies requirements for eight grades of heat-treated cast carbon steels for general engineering purposes. Four of the grades have a restricted chemical composition to ensure uniform weldability. A

GRADE & HEAT TREATMENT Grade and UNS 200-400 200-400W

C

230-450 230-450W

C

270-480 270-480W

C

340-550 340-550W

C

Heat Treatment

B

Tensile Strength ksi

MPa

400 550 400 550 450 600 450 600 480 630 480 630 550 700 550 700

MECHANICAL PROPERTIES (minimum unless range given) Yield D Strength G Red G Elong Other Tests A % Impact (J) ksi Mpa % 200

25

25

30

200

25

25

45

230

22

22

25

230

22

22

45

H

C

I

0.25

0.25

270

E

18

18

22

270

E

18

18

22

340

F

15

15

20

340

F

15

15

20

0.25

0.25

A

Mn

1.00

1.20

1.20

1.50

P

CHEMICAL COMPOSITION , % (maximum percent unless range given) SPECIFIED RESIDUAL ELEMENTS Maximum % S Si Total J J J Ni Cr Mo Cu V Content J %

0.035

0.035

0.035

0.035

0.035

0.035

0.035

0.035

0.035

0.035

0.035

0.035

0.035

0.035

0.035

0.035

0.60

0.40

0.35

0.15 0.40

0.05

1.00

0.60

0.40

0.35

0.15 0.40

0.05

1.00

0.60

0.40

0.35

0.15 0.40

0.05

1.00

0.60

0.40

0.35

0.15 0.40

0.05

1.00

See original specification for additional details on mechanical properties The type of heat-treatment is left to the discretion of the manufacturer, unless specifically agreed upon at the time of ordering The W-grades restrict the chemical composition and may be ordered to ensure uniform weldability D If measurable, the upper yield stress, otherwise the 0.2% proof stress E The casting will have an upper yield stress of [260 Mpa] and a tensile strength of [500-650 MPa] in sections from [28 mm] up to [40 mm] F The casting will have an upper yield stress of [300 Mpa] and a tensile strength of [570-720 MPa] in sections from [28 mm] up to [40 mm] G By choice, according to the order H The choice of chemical composition in the non-weldable grades shall be left to the discretion of the manufacturer I For each 0.01% reduction of carbon below 0.25%, an increase of 0.04% manganese above the maximum specified will be permitted, to a maximum of 1.20% for grade 200-400W and to 1.40% for grade 270-480W J Maximum content of residual elements, the sum of which shall not exceed 1.00% B C

22

ISO 4991

STEEL CASTINGS FOR PRESSURE PURPOSES This International Standard covers steel castings used for pressure purposes. It includes materials which are used for the manufacture of components subject to pressure vessel codes (see ISO/R831, ISO 2694 and ISO 5730) and for other pressure containing components not subject to codal requirements 3)


Heat Treatment

5)

MECHANICAL PROPERTIES AT ROOM TEMPERATURE (minimum unless range given) 6) 7) 7), 4) 3), 4) Re Rm A Z KV KV Min Min Min Min at Min 2 2 N/mm N/mm % % J °C J

1),2)

CHEMICAL COMPOSITION, % (m/m) (maximum percent unless range given) C

Si

Mn

P

S

Cr

Mo

Ni

V

Unalloyed steels C23-45A

240

C23-45AH

240

C23-45B

240

C23-45BH

240

C23-45BL

240

C26-52

280

C26-52H

280

C26-52L

280

450 600 150 300 450 600 450 600 450 300 10) 520 670 10) 520 670 10) 520 670

22

35

27

22

35

27

22

35

45

22

35

45

0.25

0.60 1.20

0.035 0.035

0.25

0.60 1.20 1.00 0.60 1.60 1.00 0.60 1.60 1.00 0.60 1.60

0.035 0.035

0.20 0.20 22

-40

27 0.20

18

30

35

18

30

35

18

-35

0.25

8),9)

0.25

8),9)

0.25

8)

27

0.035 0.035 0.035 0.035 0.030 0.030

0.60 1.20

8),9)

0.035 0.035

0.60 1.20

8),9)

0.035 0.035

0.60 1.20

8)

0.03

0.03

Alloyed ferritic and martensitic steels C28H

250

C31L

370

C32H

290

C33H

320

C34AH

280

C34BH

390

C34BL

390

C35BH

420

C37H

420

C38H

420

C39CH

450

C39CNiH

360

450 600 550 700 490 640 500 650 510 660 600 750 600 750 590 740 630 780 630 780 620 770 540 690

21

25

25

16

30

18

35

27

17

30

13

18

35

25

18

35

40

0.15 0.23 -45

18

0.29 0.10 10) 0.20 0.10 0.17 0.08 0.15 0.13 0.20 50

15

35

24

16

35

25

16

35

20

14

30

20

18

35

35

27

27 0.20 0.13 0.20 0.12 0.19 0.10 0.17 0.10 0.17 0.05 0.10

23

0.30 0.60 0.30 0.60 0.30 0.60 0.30 0.60 0.30 0.60 0.30 0.60 0.30 0.60 0.30 0.60

0.50 1.00 0.50 0.80 0.50 0.80 0.40 0.70 0.50 0.80 0.50 0.80 0.50 0.80 0.50 0.80 0.50 0.80 0.80 0.50 0.80 0.80 0.80 1.00 0.40 0.80 0.80

0.035 0.035 0.30 0.90 0.030 0.030 1.20 1.00 0.035 0.035 1.50 0.30 0.035 0.035 0.60 2.00 0.035 0.035 2.50 2.00 0.035 0.035 2.50 2.00 0.030 0.030 2.50 1.20 11) 0.035 0.035 1.60 4.00 0.035 0.035 6.00 8.00 0.035 0.035 10.0 11.5 0.035 0.035 13.5 11.5 0.035 0.035 13.0

0.40 0.60 0.15 1.30 0.45 0.65 0.40 0.22 0.60 0.40 0.32 0.90 1.20 0.90 1.20 0.90 1.20 0.90 0.15 12) 1.20 0.35 0.45 0.65 1.00 1.30 0.50 1.00 0.20 0.80 0.50 1.80

Nb

3)

GRADE & HEAT TREATMENT Grade and UNS C39NiH C39NiL C40H C43L C43C1L C43E2aL C43E2bL

Heat Treatment

5)

MECHANICAL PROPERTIES AT ROOM TEMPERATURE (minimum unless range given) 6) 7) 7), 4) 3), 4) Re Rm A Z KV KV Min Min Min Min at Min 2 2 N/mm N/mm % % J °C J 550 750 15 35 45 900 550 750 15 35 -80 27 900 13) 540 740 15 20 21 880 300 460 20 -70 27 610 380 520 20 -35 27 670 450 620 16 -80 27 800 655 800 13 -60 27 950

1),2)


Si

Mn

0.08

1.00 1.50

0.08 0.20 0.26

1.00 0.20 0.40 0.30 0.60 0.30 0.60

0.22

1.50 0.50 0.70 0.50 0.80 0.80 1.20 0.40 0.60 0.80 0.40 0.60 0.80

0.03

2.00 2.00

0.07 0.04 0.10

2.00 2.00

0.07

2.00 2.00

0.08

2.00 2.00

0.03

2.00 2.00

0.07 0.04 0.10

2.00 2.00

0.08

2.00 2.00

0.03

2.00 2.00

0.07

2.00 2.00

0.14 0.24 0.22

P

S

Cr

11.5 0.035 0.035 13.5 11.5 0.030 0.030 13.5 11.3 0.035 0.035 12.3

Mo

Ni

V

1.35 0.030 0.030 2.00 1.50 0.030 0.030 2.00

3.50 1.00 5.00 3.50 1.00 5.00 1.00 0.70 0.25 1.20 1.00 0.35 3.00 4.00 0.15 1.50 0.30 2.00 0.35 2.50 0.60 3.50 0.35 2.75 0.60 3.90

17.0 0.045 0.035 19.0 18.0 0.045 0.035 21.0 18.0 0.045 0.035 21.0 17.0. 0.045 0.035 20.0 18.0 0.045 0.035 21.0 17.0 0.045 0.035 21.0 17.0 0.045 0.035 21.0 17.0 0.045 0.035 21.0 17.0 0.045 0.035 21.0 17.0 0.045 0.035 21.0 17.0 0.045 0.035 21.0

9.0 12.0 8.0 11.0 8.0 12.0 9.0 12.0 9.0 12.0 9.0 13.0 9.0 13.0 9.0 13.0 9.0 13.0 9.0 13.0 9.0 13.0

0.030 0.030 0.030 0.030

Nb

Austenitic stainless steels C46

210

C47

210

C47H

230

C47L

210

C50

210

C57

210

C60

210

C60H

230

C60Nb

210

C61LC

210

C61

210

440 640 440 640 470 670 440 640 440 640 440 620 440 640 470 670 440 640 440 640 440 640

30

14)

30

14)

30

14)

30

-195

25

14)

30

14)

30

14)

30

14)

25

14)

30

14)

30

14)

15)

2.00 2.00

45

1.

2.00 2.00

2.0 2.5 2.0 2.5 2.0 2.5 2.0 2.5 2.5 3.0 2.5 3.0

8x%C 1.0

8x%C 1.0

Elements not quoted in this table shall not be intentionally added without the purchaser’s agreement, other than for the purpose of finishing the heat treatment. For unalloyed steels, if not otherwise agreed, the following maximum values, in percentage, are applicable: Cr/0.40, Mo/0.15, Ni/0.40, V/0.03, Cu/0.40, (Cr+Mo+Ni+V Cu)/100 2. The permissible deviatons for the results of check-analysis on test blocks shall be as specified in ISO 4990. 3. Re: yield strength (see footnote 5); Rm: tensile strength; A percentage elongation after fracture on original gage length Lo=5.65 √ So (Where So is the original cross-sectional area); Z:reduction of area; KV: ISO V-notch impact strength. 4. The given minimum values apply for the average of three individual test results. One of the individual values may be below the specified minimum average value, provided it is not less than 70% of that value. 5. Refer to specifications for heat treatment requirements 6. The values of Re shall be regarded as complied with if, in the case of non-austentic steels, the upper yield stress (ReH), the total 0.5% total elongation proof stress(Rt0.5) or the 0.2% proof test (Rp0.2) satisfy the specified values.

24

7.

The minimum values for either Z or KV apply. Unless otherwise specified, the choice is lift to the manufacturer. However, the purchaser shall note that some national or ISO codes require the testing of impact specimens. 8. For each 0.0.01 % (m/m) C below the maximum carbon content, an increase of 0.04 % (m/m) Mn will be permitted up to a maximum manganese content of 1.40 % (m/m). 9. For certain applications and upon agreement at the time of the enquiry and order, this grade of steel can be supplied with a maximum carbon content of 0.30% (m/m) and a maximum manganese content of 0.90% (m/m). 10. 2 If the minimum yield strength Re is met, tensile strength (Rm) values down to 500 N/mm should be regarded as acceptable. 11. For castings with thin sections, a minimum value of 1.00 % (m/m) Cr may be agreed upon. 12. Depending on the wall thickness, a nickel content of less than 1.00% (m/m) is permitted. 13. This type of steel is usually applied only at temperatures above 525° C. 14. Austenitic steels normally have a high toughness because of their structure. 15. Valid for an impact value of 45J. Normally, this value is also to be expected for the room temperature grade. If, however, the low temperature grade is ordered, the value has to be verified by testing.

ISO 9477

HIGH STRENGTH CAST STEELS FOR GENERAL ENGINEERING AND STRUCTURAL PURPOSES This International Standard specifies requirements for four grades of heat-treated cast carbon and alloy steels for general engineering and structural purposes. A

GRADE & HEAT TREATMENT Grade and UNS 410-620

Heat Treatment

Tensile Strength ksi MPa 620 770 720 870 820 970 1030 1180

B

540-720 620-820 840-1030 A B

MECHANICAL PROPERTIES (minimum unless range given) Yield Strength Elong Red A % % ksi MPa 410 16 40

CHEMICAL COMPOSITION, % (maximum percent unless range given) Other Tests Impact (J) 20

540

14

35

20

620

11

30

18

840

7

22

15

P

S

Si

0.035

0.035

0.60

0.035

0.035

0.60

0.035

0.035

0.60

0.035

0.035

0.60

See original specification for additional details on mechanical properties The type of heat-treatment is left to the discretion of the manufacturer, unless specifically agreed upon at the time of ordering

ISO 13521

AUSTENITIC MANGANESE STEEL CASTINGS This International Standard specifies austenitic manganese cast steels for wear resistant service. The grades covered by this International Standard will experience maximum service life in applications where the surface of the castings is subject to impact.

GRADE & HEAT TREATMENT Grade and UNS GX120MnMo7-1 GX110MnMo12-1 GX100Mn13

A

GX120Mn13

A

Heat Treatment


MPa

MECHANICAL PROPERTIES (minimum unless range given) Yield Elong Red A Strength % %

ksi

GX120MnCr13-3

Other Tests

c

C

Mn

P

S

0.060

0.045

0.060

0.045

0.060

0.045

0.060

0.045

0.060

0.045

0.060

0.045

Si

Ni

Cr

Mo

MPa

1.05 1.35 0.75 1.35 0.90 1.05 1.05 1.35 1.05 1.35 1.05 1.35

ST & WQ ST & WQ ST & WQ

GX120MnCr13-2


ST & WQ ST & WQ & WQ

25

6.0 8.0 11.0 14.0 11.0 14.0 11.0 14.0 11.0 14.0 11.0 14.0

0.30 0.90 0.30 0.90 0.30 0.90 0.30 0.90 0.30 0.90 0.30 0.90

0.90 1.20 0.90 1.20

1.50 2.50 3.0 4.0

GRADE & HEAT TREATMENT Grade and UNS GX120Mn17

Heat Treatment


A

ST & WQ

GX90MnMo14

MPa

MECHANICAL PROPERTIES (minimum unless range given) Yield Elong Red A Strength % %

ksi

CHEMICAL COMPOSITION, % (maximum percent unless range given) Other Tests

c

1.05 1.35 0.70 1.00 1.05 1.35

B

as cast

GX120MnCr17-2

C

Mn

P

S

0.060

0.045

0.070

0.045

0.060

0.045

Si

Ni

Cr

Mo

MPa

ST & WQ

16.0 19.0 13.0 15.0 16.0 19.0

0.30 0.90 0.30 0.60 0.30 0.90

1.00 1.80 1.50 2.50

A

These grades are sometimes used for non-magnetic service For castings with thicknesses less than [45 mm] and containing less than 0.8% carbon, heat treatment is not required C Bend test, hardness test, and microstructure shall be performed when agreed upon between the purchaser and the manufacturer – see original specification for more details B

ISO 14737

CAST CARBON AND LOW ALLOY STEELS FOR GENERAL USE

GRADE & HEAT TREATMENT Grade and UNS GS200 GS230 GS270 GS340

Heat Treatment +N +N +N +N +N

G20Mn5

+QT +N

G28Mn6

+QT1 +QT2 +QT1

G28MnMo6

+QT1 +QT2

G20Mo5 G10MnMoV6-3

+QT2 +NT

MECHANICAL PROPERTIES AT ROOM TEMPERATURE (minimum unless range given) Thickness Tensile test Impact Test KV Rp0.2 Rm A t Min min Min mm J MPa MPa % 100 200 400 25 45 550 100 230 450 22 45 600 100 270 480 18 27 630 100 340 550 15 20 700 30 300 480 20 50 620 100 300 500 22 60 650 250 260 520 18 31 670 100 450 600 14 35 750 50 550 700 10 31 850 50 500 700 12 35 850 100 480 670 10 31 830 100 590 850 8 27 1000 100 245 440 22 27 590 50 380 500 22 60 650

26


Si

0.18

0.60

1.20

0.030

0.025

0.30

A

0.12

A

0.40

A

0.03

A

0.30

A

0.22

0.60

1.20

0.030

0.025

0.30

A

0.12

A

0.40

A

0.03

A

0.30

A

0.24

0.60

1.30

0.030

0.025

0.30

A

0.12

A

0.40

A

0.03

A

0.30

A

0.30 0.17 0.23 0.17 0.23 0.25 0.32 0.25 0.32 0.25 0.32 0.25 0.32 0.25 0.32 0.25 0.32 0.15 0.23

0.60

0.030

0.025

0.30

A

0.12

A

0.40

A

0.03

A

0.30

A

0.030

0.020

B

0.30

0.15

0.80

0.05

0.30

0.030

0.020

B

0.30

0.15

0.80

0.05

0.30

0.030

0.025

0.30

0.15

0.40

0.05

0.30

0.030

0.025

0.30

0.15

0.40

0.05

0.30

0.030

0.025

0.30

0.05

0.30

0.025

0.025

0.30

0.40

0.05

0.30

0.025

0.025

0.30

0.40

0.05

0.30

0.025

0.025

0.40

0.05

0.30

0.40

0.05 0.05 0.10

0.30

0.60

0.15 0.20 0.40 0.20 0.40 0.20 0.40 0.40 0.60 0.20 0.40

0.40

0.12

1.50 1.00 1.60 1.00 1.60 1.20 1.80 1.20 1.80 1.20 1.80 1.20 1.60 1.20 1.60 1.20 1.60 0.50 1.00 1.20 1.80

0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60

Mn

P

S

0.025

0.020

0.025

0.020

Cr

0.30 B

0.30 0.30

Mo

Ni

0.40

V

Nb

0.30


Heat Treatment +NT +NT +NT +QT +QT

C

+QT

C

+QT

C

+N G20NiCrMo2-2

+QT1 +QT2 +N

G25NiCrMo2-2

+QT1 +QT2 +N

G30NiCrMo2-2

+QT1 +QT2

G17CrMo5-5 G17CrMo5-10

+QT +QT +QT1

G25CrMo4

+QT1 +QT2

G32CrMo4

+NT +QT1 +QT1

MECHANICAL PROPERTIES AT ROOM TEMPERATURE (minimum unless range given) Thickness Tensile test Impact Test KV Rp0.2 Rm A t Min min Min mm J MPa MPa % 50 350 480 22 60 100 630 100 330 480 20 60 150 630 150 330 450 18 60 250 600 50 500 600 18 60 750 50 400 550 18 60 100 700 100 380 500 18 60 150 650 150 350 460 18 60 250 610 100 200 550 18 10 700 100 430 700 15 25 850 100 540 820 12 25 970 100 240 600 18 10 750 100 500 750 15 25 900 100 300 850 12 25 1000 100 270 630 18 10 780 100 540 820 14 25 970 100 630 900 11 25 1050 100 315 490 20 27 690 150 100 590 18 40 740 100 450 600 16 40 750 100 300 550 14 27 250 700 100 550 700 10 18 850 100 270 630 16 10 780 100 540 700 12 35 850 100 480 620 10 27 150 770

27


Si

0.12

0.60

0.12

0.60

0.12

0.60

0.12

0.60

0.12

0.60

0.12

0.60

0.12 0.18 0.23 0.18 0.23 0.18 0.23 0.23 0.28 0.23 0.28 0.23 0.28 0.28 0.33 0.28 0.33 0.28 0.33 0.15 0.20 0.13 0.20 0.22 0.29 0.22 0.29 0.22 0.29 0.28 0.35 0.28 0.35 0.28 0.35

0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60

Mn 1.20 1.80 1.20 1.80 1.20 1.80 1.20 1.80 1.20 1.80 1.20 1.80 1.20 1.80 0.60 1.00 0.60 1.00 0.60 1.00 0.60 1.00 0.60 1.00 0.60 1.00 0.60 1.00 0.60 1.00 0.60 1.00 0.50 1.00 0.50 0.90 0.50 0.80 0.50 0.80 0.50 0.80 0.50 0.80 0.50 0.80 0.50 0.80

P

S

Cr

0.025

0.020

0.30

0.025

0.020

0.30

0.025

0.020

0.30

0.025

0.020

0.30

0.025

0.020

0.30

0.025

0.020

0.30

0.025

0.020

0.035

0.030

0.035

0.030

0.035

0.030

0.035

0.030

0.035

0.030

0.035

0.030

0.035

0.020

0.035

0.020

0.035

0.020

0.30 0.40 0.60 0.40 0.60 0.40 0.60 0.40 0.60 0.40 0.60 0.40 0.60 0.40 0.60 0.40 0.60 0.40 0.60 1.00 1.50 2.00 2.50 0.80 1.20 0.80 1.20 0.80 1.20 0.80 1.20 0.80 1.20 0.80 1.20

0.025

0.020

B

0.025

0.020

B

0.025

0.020

B

0.025

0.020

B

0.025

0.020

B

0.025

0.020

B

0.025

0.020

B

0.020

B

0.025

Mo 0.20 0.40 0.20 0.40 0.20 0.40 0.20 0.40 0.20 0.40 0.20 0.40 0.20 0.40 0.15 0.25 0.15 0.25 0.15 0.25 0.15 0.25 0.15 0.25 0.15 0.25 0.15 0.25 0.15 0.25 0.15 0.25 0.45 0.65 0.90 1.20 0.15 0.25 0.15 0.25 0.15 0.25 0.15 0.25 0.15 0.25 0.15 0.25

Ni

0.40 0.40 0.40 0.40 0.40 0.40 0.40 0.40 0.70 0.40 0.70 0.40 0.70 0.40 0.70 0.40 0.70 0.40 0.70 0.40 0.70 0.40 0.70 0.40 0.70

V 0.05 0.10 0.05 0.10 0.05 0.10 0.05 0.10 0.05 0.10 0.05 0.10 0.05 0.10

Nb

0.30 0.30 0.30 0.30 0.30 0.30 0.30

0.05

0.30

0.05

0.30

0.05

0.30

0.05

0.30

0.05

0.30

0.05

0.30

0.05

0.30

0.05

0.30

0.05

0.30

0.40

0.05

0.30

0.40

0.05

0.30

0.40

0.05

0.30

0.40

0.05

0.30

0.40

0.05

0.30

0.40

0.05

0.30

0.40

0.05

0.30

0.40

0.05

0.30


Heat Treatment +QT1 +QT2 NT +QT1

G42CrMo4

+QT1 +QT1 +QT2

G50CrMo4

+QT +QT1 +QT1

G30CrMoV6-4

+QT1 +QT2 +N +N +QT1

G35CrNiMo6-6

+QT1 +QT1 +QT2 +NT

G30NiCrMo7-3

+QT1 +QT2 +NT

G40NiCrMo7-3

+QT1 +QT2

MECHANICAL PROPERTIES AT ROOM TEMPERATURE (minimum unless range given) Thickness Tensile test Impact Test KV Rp0.2 Rm A t Min min Min mm J MPa MPa % 150 330 620 10 16 250 770 100 350 800 10 18 950 100 300 700 15 10 850 100 600 780 12 31 930 100 550 700 10 27 150 850 150 350 650 10 16 250 800 100 700 850 10 18 1000 100 750 900 10 18 1050 100 700 850 14 45 1000 100 550 750 12 27 150 900 150 350 650 12 20 250 800 100 750 900 12 31 1100 150 550 800 12 31 950 150 500 750 12 31 250 900 100 700 850 12 45 1000 100 650 800 12 35 150 950 150 650 800 12 30 250 950 100 800 900 10 35 1050 100 550 760 12 10 900 100 690 930 10 25 1100 100 795 1030 8 25 1200 100 585 860 10 10 1100 100 760 1000 8 25 1140 100 795 1030 8 25 1200

28

CHEMICAL COMPOSITION, % (m/m) (maximum percent unless range given) C 0.28 0.35 0.28 0.35 0.38 0.45 0.38 0.45 0.38 0.45 0.38 0.45 0.38 0.45 0.46 0.53 0.27 0.34 0.27 0.34 0.27 0.34 0.27 0.34 0.32 0.38 0.32 0.38 0.32 0.38 0.32 0.38 0.32 0.38 0.32 0.38 0.28 0.33 0.28 0.33 0.28 0.33 0.38 0.43 0.38 0.43 0.38 0.43

Si

0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60 0.60

Mn 0.50 0.80 0.50 0.80 0.60 1.00 0.60 1.00 0.60 1.00 0.60 1.00 0.60 1.00 0.60 1.00 0.60 1.00 0.60 1.00 0.60 1.00 0.60 1.00 0.60 1.00 0.60 1.00 0.60 1.00 0.60 1.00 0.60 1.00 0.60 1.00 0.60 0.90 0.60 0.90 0.60 0.90 0.60 0.90 0.60 0.90 0.60 0.90

P

S

Cr

0.020

B

0.025

0.020

B

0.025

0.020

B

0.025

0.020

B

0.025

0.020

B

0.025

0.020

B

0.025

0.020

B

0.025

0.020

B

0.025

0.020

B

0.025

0.020

B

0.025

0.020

B

0.025

0.020

B

0.025

0.020

B

0.025

0.020

B

0.025

0.020

B

0.025

0.020

B

0.025

0.020

B

0.025

0.020

B

0.035

0.030

0.035

0.030

0.035

0.030

0.035

0.030

0.035

0.030

0.035

0.030

0.025

0.80 1.20 0.80 1.20 0.80 1.20 0.80 1.20 0.80 1.20 0.80 1.20 0.80 1.20 0.80 1.20 1.30 1.70 1.30 1.70 1.30 1.70 1.30 1.70 1.40 1.70 1.40 1.70 1.40 1.70 1.40 1.70 1.40 1.70 1.40 1.70 0.70 0.90 0.70 0.90 0.70 0.90 0.70 0.90 0.70 0.90 0.70 0.90

Mo 0.15 0.25 0.15 0.25 0.15 0.25 0.15 0.25 0.15 0.25 0.15 0.25 0.15 0.25 0.15 0.25 0.30 0.50 0.30 0.50 0.30 0.50 0.30 0.50 0.15 0.35 0.15 0.35 0.15 0.35 0.15 0.35 0.15 0.35 0.15 0.35 0.20 0.30 0.20 0.30 0.20 0.30 0.20 0.30 0.20 0.30 0.20 0.30

Ni

V

0.40

0.05

0.30

0.40

0.05

0.30

0.40

0.05

0.30

0.40

0.05

0.30

0.40

0.05

0.30

0.40

0.05

0.30

0.40

0.05

0.30

0.40

0.05 0.05 0.15 0.05 0.15 0.05 0.15 0.05 0.15

0.30

0.05

0.30

0.05

0.30

0.05

0.30

0.05

0.30

0.05

0.30

0.05

0.30

0.05

0.30

0.05

0.30

0.05

0.30

0.05

0.30

0.05

0.30

0.05

0.30

0.40 0.40 0.40 0.40 1.40 1.70 1.40 1.70 1.40 1.70 1.40 1.70 1.40 1.70 1.40 1.70 1.65 2.00 1.65 2.00 1.65 2.00 1.65 2.00 1.65 2.00 1.65 2.00

Nb

0.30 0.30 0.30 0.30


Heat Treatment +QT1

G32NiCrMo8-5-4

+QT1 +QT2

A B C

MECHANICAL PROPERTIES AT ROOM TEMPERATURE (minimum unless range given) Thickness Tensile test Impact Test KV Rp0.2 Rm A t Min min Min mm J MPa MPa % 100 700 850 16 50 1000 100 650 820 14 35 250 970 100 980 1050 10 35 1200

CHEMICAL COMPOSITION, % (m/m) (maximum percent unless range given) C 0.28 0.35 0.28 0.35 0.28 0.35

Si

0.60 0.60 0.60

Mn 0.60 1.00 0.60 1.00 0.60 1.00

P

S

0.020

0.015

0.020

0.015

0.020

0.015

Cr 1.00 1.40 1.00 1.40 1.00 1.40

Mo 0.30 0.50 0.30 0.50 0.30 0.50

Ni 1.60 2.10 1.60 2.10 1.60 2.10

V

Nb

0.05

0.30

0.05

0.30

0.05

0.30

Cr+Mo+Ni+V+Cu max. 100% For castings of ruling thickness<28 mm, S≤0.030% is permitted. Cooling in liquid

MIL-C-24707/1

CASTINGS, FERROUS, FOR MACHINERY AND STRUCTURAL APPLICATIONS This specification covers steel castings for machinery and structural applications below 775 F where impact strength may be a consideration.

PREVIOUS SPECIFICATION MIL-S-15083B (grade) (CW) (B) (65-35) (70-36) (80-40) (80-50) (90-60) (100-70) (105-85) (120-95) (150-125)

REPLACEMENT SPECIFICATION MIL-C-24707/1 ASTM specification (grade) A 757 (A1Q) or A 216 (WCA) A 757 (A1Q) or A 216 (WCA) A 757 (A1Q) or A 216 (WCB) A 757 (A2Q) or A 216 (WCB, WCC) A 757 (A2Q) or A 487 (2 class A, B, C) A 757 (C1Q) or A 487 (2 class A, B, C) A 757 (E1Q) or A 487 (4 class A) A 757 (E2N1/E2Q1) A 757 (E2N2/E2Q2) or A 487 (4 class B) A 757 (E2N3/E2Q3) or A 487 (14 class A) Special application only

FEDERAL GRADE QQ-S-681F ASTM specification (grade) A 27 (N-1) A 27 (N-2) A 27 (U60-30) A 27 (60-30) A 27 (65-35) A 27 (70-36) A 27 (70-40) A 148 (80-40) A 148 (80-50) A 148 (90-60) A 148 (105-85) A 148 (120-95)

EQUIVALENT GRADE MIL-C-24707/1 ASTM specification (grade) A 757 (A1Q) or A 216 (WCA) or A 217 (WC1) A 757 (A1Q) or A 216 (WCA) or A 217 (WC1) A 757 (A1Q) or A 216 (WCB) or A 217 (WC1) A 757 (A1Q) or A 216 (WCB) or A 217 (WC1) A 757 (A1Q) or A 216 (WCB) or A 217 (WC1) A 757 (A2Q) or A 216 (WCB, WCC) A 757 (A2Q) or A 216 (WCC) A 757 (A2Q) or A 487 (2 class A, B, C) A 757 (C1Q) or A 487 (2 class A, B, C) A 757 (E1Q) or A 487 (4 class A) A 757 (E2N2/E2Q2) or A 487 (4 class B) A 757 (E2N3/E2Q3) or A 487 (14 class A)

Additional notes for specification are as follows; see original military specification booklet for further information, including Quality Assurance Provisions. The specified residual elements shall be determined for carbon steels. When no impact requirement is given, there shall be a requirement of 20 ft-lbs @ 10 F; except for deck applications, which shall meet a requirement of 20 ft-lbs @ -20 F. When specified, the stress relieving temperature shall be 50 F [30 C] but not more than 100 F [60 C] below the tempering temperature; mechanical properties shall be determined after the stress relief heat treatment.

29

MIL-C-24707/2

CASTINGS, FOR PRESSURE CONTAINING PARTS SUITABLE FOR HIGH TEMPERATURE SERVICE This specification covers alloy steel castings for machinery, structural, and pressure containing parts for high temperature applications.

PREVIOUS SPECIFICATION MIL specification (grade) MIL-S-870B MIL-S-15464B(SHIPS) (1) MIL-S-15464B(SHIPS) (2) MIL-S-15464B(SHIPS) (3)

REPLACEMENT SPECIFICATION MIL-C-24707/2 ASTM specification (grade) A 217 (WC1) A 217 (WC6) A 217 (WC9) A 389 (C23)

Additional notes for specification are as follows; see original military specification booklet for further information, including Quality Assurance Provisions. When specified, the stress relieving temperature shall be 50 F [30 C] but not more than 100 F [60 C] below the tempering temperature; mechanical properties shall be determined after the stress relief heat treatment.

MIL-S-870B

STEEL CASTINGS, MOLYBDENUM ALLOY

Canceled January 27, 1989 – use MIL-C-24707/2, grade WC1

MIL-S-15083B(NAVY)

STEEL CASTINGS

Canceled January 27, 1989 – use MIL-C-24707/1, ASTM A757, A216, A487

MIL-S-15464B(SHIPS)

STEEL ALLOY, CHROMIUM-MOLYBDENUM; CASTINGS

Canceled January 27, 1989 – use MIL-C-24707/2, ASTM A217, A389

MIL-S-23008D(SH)

STEEL CASTINGS, ALLOY, HIGH YIELD STRENGTH (HY-80 AND HY-100)

Canceled June 5, 2003-

MIL-S-46052A(MR)

STEEL CASTINGS, HIGH STRENGTH, LOW ALLOY This specification covers high strength, low alloy, steel castings.

Canceled May 31, 1983 – use ASTM A 148 / A148M

30

SAE J435c

AUTOMOTIVE STEEL CASTINGS These specifications cover steel castings used in the automotive and allied industries (last revised Oct 2002).

GRADE & HEAT TREATMENT New Old Grade Grade 0000 0022 415 450 585 690 550 620 725 830 1035 1205 A

CHEMICAL COMPOSITION, % (maximum percent unless range given) C

Mn

0.12 0.22

0.50 0.90

0.25

0.75

0.30 0.40 0.50 0.40 0.50

0.70 0.50 0.90 0.50 0.90

0025 0030 0050A 0050B

Si

P

S

0.60

0.040

0.045

A

0.80

0.040

0.045

A

0.80

0.040

0.045

0.80

0.040

0.045

0.80

0.040

0.045

0.040

0.045

0.040

0.045

0.040

0.045

0.040

0.045

0.040

0.045

0.040

0.045

080 090 0105 0120 0150 0175


MPa

MECHANICAL PROPERTIES (minimum unless range given) Yield Strength Elong Red A Ksi MPa % %

Other Tests Hardness (BHN) 187

60

415

30

205

22

30

187

65

450

35

240

24

35

85

585

45

310

16

24

100

690

70

485

10

15

80

550

50

345

22

35

90

620

60

415

20

40

105

725

85

585

17

35

120

830

95

655

14

30

150

1035

125

860

9

22

175

1205

145

999.7

6

21

131 187 170 229 207 255 163 207 187 241 217 248 248 311 311 363 363 415

For each reduction of 0.01% carbon below the maximum specified, an increase of 0.04% manganese above the maximum specified will be permitted to a maximum of 1% manganese

31

SUMMARY OF MATERIAL SPECIFICATIONS FOR HIGH ALLOY CAST STEELS

The American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code makes extensive use of ASTM specifications with slight modifications. For the sake of comparison the ASME specifications use the preface SA so that SA 351 is related to ASTM A 351/A 351M. However, while ASTM A 351/A 351M could be used for comparison of grades, the ASME SA 351 contained in Section II must be used when complying with the code. Cast stainless steels are most often specified on the basis of composition using the alloy designation system adopted by the Alloy Casting Institute (ACI). These ACI alloy designations, e.g. CF-8M, have been adopted by ASTM and are preferred for cast alloy over the corresponding wrought steel designation of the American Iron and Steel Institute (AISI). The reason for this is that the grades intentionally have different compositions than their wrought counterparts. The ranges of iron, chromium, and nickel for the cast alloy compositions most widely used are identified with a letter which is part of the ACI grade designation. The initial letter of the grade designation, C or H, indicates whether the alloy is intended primarily for aqueous corrosion service (C) or elevated temperature, i.e. heatresistant, service (H). The second letter of the ACI designation denotes the nominal chromium-nickel type. As the nickel content of the grade increases, the letter in the ACI designation increases from A (lowest) to Z (highest). Numerals following the letters relate to the maximum carbon content of the corrosion-resistant (C) alloys. When used with heat resistant grades (H), the numerals are the midpoint of a 0.10 carbon range. If additional alloying elements are included in the grade, they are denoted by the addition of a letter to the ACI designation. Thus, CF-8M is an alloy for corrosion resistant service of the 19% Cr and 9% Ni type with a maximum carbon content of 0.08% and which contains molybdenum. The CF grade alloys constitute the most technologically important and highest tonnage segment of corrosionresistant casting production. These 19Cr-9Ni alloys are the cast counterparts of the 18Cr-8Ni or AISI 300 series wrought stainless steels. In general, the cast and wrought alloys possess equivalent resistance to corrosive media and they are frequently used in conjunction with each other. Important differences do exist, however, between the cast CF grade alloys and their wrought AISI counterparts. Most significant among these is the difference in alloy microstructure in the end-use condition. The CF grade cast alloys are duplex ferrite-in-austenite and usually contain from 5 to 40% ferrite, depending on the particular alloy, whereas their wrought counterparts are fully austenitic. The ferrite in cast stainless with duplex structures is magnetic, a point that is often confusing when cast stainless steels are compared to their wrought counterparts by checking their attraction to a magnet. This difference in microstructures is attributable to the fact that the chemical compositions of the cast and wrought alloys are different by intent. Ferrite is present by intent in cast CF grade stainless steels for three reasons: to provide strength, to improve weldability, and to maximize resistance to corrosion in specific environments. Below is a list of high alloy cast steel specifications, with summary details on the following pages. Note that the values given in the summary of the specifications are stated with either U.S. Conventional Units (USCS) or Metric (SI) units, and are to be regarded separately. Units given in brackets are SI units. The values stated in each system are not exact equivalents (soft conversion); therefore, each system must be used independently of the other. Combining values from the two systems, by using conversion equations (hard conversion), may result in nonconformance with the specification. Also note that the values in the table are given in a minimum over maximum format. This means that if the value is a minimum it will be listed in the upper portion of the specification’s table row and in the lower portion of the row if it is a maximum value. Finally, note that tables and their footnotes may be split across two or more pages.

32

ASTM A 128/A128M – 07 ASTM A 297/A 297M – 08 ASTM A 351/A 351M – 06 ASTM A 447/A 447M – 07 ASTM A 494/A 494M – 08 ASTM A 560/A 560M – 05 ASTM A 743/A 743M – 06 ASTM A 744/A 744M – 06 ASTM A 747/A 747M – 07 ASTM A 890/A 890M – 07 ASTM A 990 – 08 ISO 11972 ISO DIS 11973 ISO 12725 ISO 19960 MIL-C-24707/3 MIL-C-24707/6

Steel Castings, Austenitic Manganese Steel Castings, Iron-Chromium and Iron-Chromium-Nickel, Heat Resistant, for General Application Castings, Austenitic, Austenitic-Ferritic, For Pressure-Containing Parts Steel Castings, Chromium-Nickel-Iron Alloy (25-12 Class), for High-Temperature Service Castings, Nickel and Nickel Alloy Castings, Chromium-Nickel Alloy Castings, Iron-Chromium, Iron-Chromium-Nickel, Corrosion Resistant, for General Application Castings, Iron-Chromium-Nickel, Corrosion Resistant, for Severe Service Steel Castings, Stainless, Precipitation Hardening Castings, Iron-Chromium-Nickel-Molybdenum Corrosion-Resistant, Duplex (Austenitic/Ferritic) for General Application Castings, Iron-Nickel-Chromium and Nickel Alloys, Specially Controlled for Pressure Retaining Parts for Corrosive Service Corrosion-resistant cast steels for general applications Heat-resistant cast steels for general purposes Nickel and nickel alloy castings Cast Steels and alloys with special physical properties. Castings, Ferrous, Corrosion-Resistant, Austenitic, Chromium-Nickel Castings, Ferrous, Chromium Steel, for Pressure-Containing Parts Suitable for HighTemperature

33

ASTM A 128/A128M – 07

STEEL CASTINGS, AUSTENITIC MANGANESE This specification covers Hadfield austenitic manganese steel castings and alloy modifications.

GRADE & HEAT A TREATMENT

B

Grade and UNS


Heat Treatment

A J91109 B-1 J91119 B-2 J91129 B-3 J91139 B-4 J91149 C J91309 D J91459 E-1 J91249 E-2 J91339 F J91340

C

Q

Mn

1.05 1.35 0.9 1.05 1.05 1.2 1.12 1.28 1.2 1.35 1.05 1.35 0.7 1.3 0.7 1.3 1.05 1.45 1.05 1.35

Q Q Q Q Q Q Q Q Q

P

S

Si

Ni

Cr

Mo

11.0 min 11.5 14.0 11.5 14.0 11.5 14.0 11.5 14.0 11.5 14.0 11.5 14.0 11.5 14.0 11.5 14.0 6.0 8.0

0.07

1.00

0.07

1.00

0.07

1.00

0.07

1.00

0.07

1.00

0.07

1.00

0.07

1.00

0.07

1.00

0.07

1.00

0.07

1.00

1.5 2.5 3.0 4.0 0.9 1.2 1.8 2.1 0.9 1.2

A

Section size precludes the use of all grades and the producer should be consulted as to grades practically obtainable for a particular design required. Final selection shall be by mutual agreement between manufacturer and purchaser. B Unless otherwise specified, Grade A will be supplied.

ASTM A 297/A 297M – 08

STEEL CASTINGS, IRON-CHROMIUM AND IRON-CHROMIUM-NICKEL, HEAT RESISTANT, FOR GENERAL APPLICATION This specification covers iron-chromium and iron-chromium-nickel alloy castings for heat-resistant service. The grades covered by this specification are general purpose alloys and no attempt has been made to include heat-resisting alloys used for special production application.

GRADE Grade and UNS HF J92603 HH J93503 HI J94003 HK J94224 HE J93403

Heat Treatment

MECHANICAL PROPERTIES (minimum unless range given) Tensile Strength Yield Strength

A

ksi

70

MPa

485

ksi

35

CHEMICAL COMPOSITION, % (maximum percent unless range given) Elong %

MPa

240

25

75

515

35

240

10

70

485

35

240

10

65

450

35

240

10

85

585

40

275

9

34

B

C 0.20 0.40 0.20 0.50 0.20 0.50 0.20 0.60 0.20 0.50

Mn

P

S

Si

2.00

0.04

0.04

2.00

2.00

0.04

0.04

2.00

2.00

0.04

0.04

2.00

2.00

0.04

0.04

2.00

2.00

0.04

0.04

2.00

Ni 8.00 12.0 11.0 14.0 14.0 18.0 18.0 22.0 8.00 11.0

Cr 18.0 23.0 24.0 28.0 26.0 30.0 24.0 28.0 26.0 30.0

Mo 0.50 0.50 0.50 0.50 0.50

C

GRADE Grade and UNS

Heat Treatment

MECHANICAL PROPERTIES (minimum unless range given) Tensile Strength Yield Strength

A

ksi

HT N08605 HU N08004 HW N08001 HX N06006 HC J92605 HD J93005 HL N08604 HN J94213 HP N08705

MPa

65

ksi

CHEMICAL COMPOSITION, % (maximum percent unless range given) Elong

B

450

4

P

S

2.00

0.04

0.04

2.50

2.00

0.04

0.04

2.50

2.00

0.04

0.04

2.50

2.00

0.04

0.04

2.50

0.50

1.00

0.04

0.04

2.00

0.50 0.20 0.60 0.20 0.60 0.35 0.75

1.50

0.04

0.04

2.00

2.00

0.04

0.04

2.00

2.00

0.04

0.04

2.00

2.00

0.04

0.04

2.50

0.35 0.75 0.35 0.75 0.35 0.75 0.35 0.75

65

450

4

60

415

60

415

55

380

75

515

35

240

8

65

450

35

240

10

63

435

62.5

430

8 34

C

%

MPa

235

4.5

Mn

Si

Ni 33.0 37.0 37.0 41.0 58.0 62.0 64.0 68.0 4.00 4.00 7.00 18.0 22.0 23.0 27.0 33 37

Cr

Mo

15.0 19.0 17.0 21.0 10.0 14.0 15.0 19.0 26.0 30.0 26.0 30.0 28.0 32.0 19.0 23.0 24 28

C

0.50 0.50 0.50 0.50 0.50 0.50 0.50 0.50 0.50

A

As-cast or as agreed upon by the manufacturer and purchaser When ICI test bars are used in tensile tests as provided for in this specification, the gage length to reduced section diameter ratio shall be 4:1 C Castings having a specified molybdenum range agreed upon by the manufacturer and the purchaser may also be furnished under these specifications B

ASTM A 351/A 351M – 06

CASTINGS, AUSTENITIC, AUSTENITIC-FERRITIC, FOR PRESSURE-CONTAINING PARTS This specification covers austenitic and austenitic-ferritic (duplex) steel castings for valves, flanges, fittings, and other pressurecontaining parts.

GRADE & HEAT TREATMENT Grade and UNS CF3 J92700 A CF3A J92700 CF8 J92600 A CF8A J92600 CF3M J92800 A CF3MA J92800 CF8M J92900 CF3MN J92804

Heat Treatment ST ST ST ST ST ST ST ST

MECHANICAL PROPERTIES (minimum unless range given) H Tensile Strength Yield Strength

B

ksi

70

MPa

485

ksi

30

MPa

205

Elong % 35.0

77

530

35

240

35.0

70

485

30

205

35.0

77

530

35

240

35.0

70

485

30

205

30.0

80

550

37

255

30.0

70

485

30

205

30.0

75

515

37

255

35.0

35


D

C

Mn

P

S

Si

0.03

1.50

0.040

0.040

2.00

0.03

1.50

0.040

0.040

2.00

0.08

1.50

0.040

0.040

2.00

0.08

1.50

0.040

0.040

2.00

0.03

1.50

0.040

0.040

1.50

0.03

1.50

0.040

0.040

1.50

0.08

1.50

0.040

0.040

1.50

0.03

1.50

0.040

0.040

1.50

Ni 8.0 12.0 8.0 12.0 8.0 11.0 8.0 11.0 9.0 13.0 9.0 13.0 9.0 12.0 9.0 13.0

Cr 17.0 21.0 17.0 21.0 18.0 21.0 18.0 21.0 17.0 21.0 17.0 21.0 18.0 21.0 17.0 21.0

Mo

N

0.50 0.50 0.50 0.50 2.00 3.00 2.00 3.00 2.00 3.00 2.00 3.00

0.10 0.20

Cb

Cu

V

GRADE & HEAT TREATMENT Grade and UNS CF8C J92710 CF-10 J92590 CF-10M J92901 CH8 J93400 CH10 J93401 CH20 J93402 CK20 J94202 HK30 J94203 HK40 J94204 HT30 N08030 CF10MC J92971 CN7M N08007 CN3MN J94651 CE8MN CG6MMN J93790 CG8M J93000 CF10SMnN J92972 CT15C N08151 CK3MCuN J93254 A,G CE20N J92802 CG3M J92999

Heat Treatment ST ST ST ST ST ST ST As cast As cast As cast ST ST ST ST

C

ST ST ST As cast ST

C

ST

C

MECHANICAL PROPERTIES (minimum unless range given) H Tensile Strength Yield Strength 70

485

30

205

Elong % 30.0

70

485

30

205

35.0

70

485

30

205

30.0

65

450

28

195

30.0

70

485

30

205

30.0

70

485

30

205

30.0

65

450

28

195

30.0

65

450

30

240

10.0

62

425

30

240

10.0

65

450

28

195

15.0

70

485

30

205

20.0

62

425

25

170

35.0

B

ksi

80

MPa

550

ksi

38

MPa

260


D

C

655

65

450

25.0

85

585

42.5

295

30.0

75

515

35

240

25.0

85

585

42.5

295

30.0

80

550

38

170 260

Si

1.50

0.040

0.040

2.00

1.50

0.040

0.040

2.00

1.50

0.040

0.040

1.50

0.08 0.04 0.10 0.04 0.20 0.04 0.20 0.25 0.35 0.35 0.45 0.25 0.35

1.50

0.040

0.040

1.50

1.50

0.040

0.040

2.00

1.50

0.040

0.040

2.00

1.50

0.040

0.040

1.75

1.50

0.040

0.040

1.75

1.50

0.040

0.040

1.75

2.00

0.040

0.040

2.50

0.10

1.50

0.040

0.040

1.50

0.07

1.50

0.040

0.040

1.50

0.03

2.00

0.040

0.010

1.00

0.08

1.00 4.00 6.00

0.040

0.040

1.50

0.040

0.030

1.00

0.04

0.04

0.10 0.05 0.15

1.50 7.00 9.00 0.15 1.50

0.060

0.03

0.03

0.03

1.50 3.50 4.50 0.15 1.50

0.025

1.20

0.045

0.010

1.00

0.20

1.50

0.040

0.040

1.50

0.03

1.50

0.04

0.04

1.50

0.08 25

S

0.08 0.04 0.10 0.04 0.10

0.06

435

P

35.0

95

63

Mn

20.0 35.0

85

550

40

275

30.0

75

515

35

240

25.0

ST

36

Ni

Cr

9.0 12.0 8.0 11.0 9.0 12.0 12.0 15.0 12.0 15.0 12.0 15.0 19.0 22.0 19.0 22.0 19.0 22.0 33.0 37.0 13.0 16.0 27.5 30.5 23.5 25.5 8.0 11.0 11.50 13.50 9.0 13.0 8.0 9.0 31.0 34.0 17.5 19.5 8.0 11.0 9.0 13.0

18.0 21.0 18.0 21.0 18.0 21.0 22.0 26.0 22.0 26.0 22.0 26.0 23.0 27.0 23.0 27.0 23.0 27.0 13.0 17.0 15.0 18.0 19.0 22.0 20.0 22.0 22.5 25.5 20.50 23.50 18.0 21.0 16.0 18.0 19.0 21.0 19.5 20.5 23.0 26.0 18.0 21.0

Mo

N

Cb

Cu

V

E

0.50 0.50 2.00 3.00 0.50 0.50 0.50 0.50 0.50 0.50 0.50 1.75 2.25 2.00 3.00 6.0 7.0 3.0 4.5 1.50 3.00 3.0 4.0

F

0.18 0.26 0.10 0.30 0.20 0.40

3.0 4.0 0.75

0.10 0.30

0.10 0.30

0.08 0.18 0.50 1.50 6.0 7.0 0.50 3.0 4.0

0.18 0.24 0.08 0.20

0.50 1.00

A

Because of thermal instability of Grades CF3A, CF3MA, CF8A, and CE20N they are not recommended for service at temperatures above 800 F [425 C] ST = to be solution treated C Refer to original specification for additional information on heat treatment requirements D When ICI test bars are used in tensile tests as provided for in Specification A 985/A 985M, the gage length to reduced section diameter ratio shall be 4:1 E Grade CF8C shall have a columbium content of not less than 8 times the carbon content but not over 1.00% F Grade CF10MC shall have a columbium content of not less than 10 times the carbon content but not over 1.20% G Grade shall be quenched in water or the castings may be furnace cooled to 2050°F(1120°C) minimum, held for 15 minutes minimum and then quenched in water or rapidly cooled by other means. H Determine by the 0.2% offset method. B

ASTM A 447/A 447M – 07

STEEL CASTINGS, CHROMIUM-NICKEL-IRON ALLOY (25-12 CLASS), FOR HIGH-TEMPERATURE SERVICE This specification covers iron-base, heat-resisting alloy castings of the 25% chromium, 12% nickel class, intended for structural elements, containers, and supports in electric furnaces, petroleum still tube supports, and for similar applications up to 2000 F [1095 C]. The purchaser should inform the manufacturer when the service temperatures are to exceed 1800 F [980 C].

GRADE & HEAT TREATMENT Grade And UNS I J93303 II J93303

Heat Treatment


A

ksi

BC

MPa

Red A %

CHEMICAL COMPOSITION, % (maximum percent unless range given) DE

Other Tests Magnetic Permeability

As cast

80

550

9

1.70

As cast

80

550

4

1.05

C 0.20 0.45 0.20 0.45

A

Mn

P

S

Si

2.50

0.05

0.05

1.75

2.50

0.05

0.05

1.75

F

Cr

10.00 14.00 10.00 14.00

23.00 28.00 23.00 28.00

Ni

N

Fe

G

0.20 0.20

As agreed upon by manufacturer and purchaser Properties after aging C Short term, high temperature tensile property requirements for the grades are as follows: Type I is to be agreed upon by manufacturer and producer, and Type II is to have a minimum of 20 ksi [140 MPa] tensile strength and a minimum elongation of 8% D The stress rupture test for the grades is as follows with the tensile stress being sustained for at least 16h: Type I at 5 ksi [34 MPa] and Type II at 8 ksi [55 MPa] E Refer to original specification for details; note that out of the four tests (tension after aging, magnetic permeability, stress rupture, and short time high-temperature) the purchaser shall specify no more than two tests F Commercial nickel usually carries a small amount of cobalt, and within the usual limits cobalt shall be counted as nickel G The manufacturer and purchaser may agree upon allowable limits of iron and other elements B

37

ASTM A 494/A 494M – 08

CASTINGS, NICKEL AND NICKEL ALLOY This specification covers nickel, nickel-copper, nickel-copper-silicon, nickel-molybdenum, nickel chromium, and nickelmolybdenum-chromium alloy castings for corrosion resistant service.

GRADE & HEAT TREATMENT Grade Heat And UNS Treatment CZ-100 As cast N02100 A M-35-1 As cast N24135 M-35-2 As cast N04020 M-30H As cast N24030 C,D M-25S F As cast or age-hardened N24025 A M-30C As cast N24130 N3M ST J30003 N-7M ST J30007 N-12MV ST N30012 CY-40 As cast or ST N06040 CW-12MW ST N30002 CW-6M ST N30107 CW-2M ST N26455 CW-6MC ST N26625 CY5SnBiM As cast N26055 CX2M ST N260022 CX2MW ST N26022 CU5MCuC F ST N28820


50

Yield Strength

MPa

345

ksi

18

MPa

125


Elong

%

E

C

450

25

170

25.0

65

450

30

205

25.0

100

690

60

415

10

P

S

Cu

1.00

1.50 2.00 0.03

0.03

0.35

1.50 1.25 0.03

0.03

0.35

1.50 2.00 2.7 1.50 3.7 3.5 1.50 4.5 1.0 1.50 2.0

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

1.25 26.0 33.0 26.0 33.0 27.0 33.0 27.0 33.0 26.0 33.0

0.30 0.25 450

32.5

225

25 0.30

76

525

40

275

20.0

76

525

40

275

20.0

76

525

40

275

485

28

195

30.0

72

495

40

275

4.0

72

495

40

275

25.0

72

495

40

275

20.0

72 80 75

485

495 550 520

40

39 45 35

275

270 280 240

Mo

0.30

1.00 0.50 0.040 0.300

0.07

1.00 1.00 0.040 0.030

0.12

1.00 1.00 0.040 0.030

0.40

1.50 3.00 0.03

0.12

1.00 1.00 0.040 0.030

0.07

1.00 1.00 0.040

0.02

1.00 0.80 0.03

0.06

1.00 1.00 0.015

0.05

1.5

0.02

1.00 0.50 0.20

0.02

1.00 0.08 0.025

30.0 33.0 30.0 33.0 26.0 30.0

6.0

70

70

Si

10.0

65

65

Mn

25.0 0.5

0.03

40 30.0 20.0 0.050 1.0

A

When weldability is needed, Grade M-35-1 or M-30C should be ordered For information only C Minimum age-hardened 300 BHN B

38

1.0

0.030

0.03

B

16.0 18.0 B 17.0 0.030 20.0 B 15.0 0.03 17.5 B 8.0 0.015 10.0 2.0 0.03 3.5 B 15.0 0.20 16.5 B 12.5 0.025 14.5 1.50 2.5 0.030 3.50 3.5

Fe

Ni

95.0 3.00 min bal. 3.50 bal. 3.50 bal. 3.50 bal. 3.50 bal. 3.50 bal. 3.00 bal. 3.0 4.0 bal. 6.0 bal. 11.0 4.5 bal. 7.5 bal. 3.0 bal. 2.0 bal. 5.0 bal. 2.0 bal. 1.5 2.0 bal. 6.0 bal. 38.0 44.0

Cr

Cb

W

V

Bi Sn

0.5 0.5 B

1.0 3.0

B

1.0

B

1.0 1.00 14.0 17.0 15.5 17.5 17.0 20.0 15.0 17.5 20.0 23.0 11.0 14.0 22.0 24.0 20.0 22.5 19.5 23.5

0.20 0.60

B

B

B

3.75 0.20 5.25 0.40

B

B

B

B

B

1.0 3.15 4.50

B

B

B

B

B

B

B

2.5 3.5

0.35

0.60 1.20

B

B

3.0 3.0 5.0 5.0

D

M-25S, while machinable in the “as cast” condition is capable of being solution treated for improved machinability; it may be subsequently age-hardened to the specified hardness and finished machined or ground E When ICI test bars are used in tensile tests as provided for per Specification A 732/A 732M, the gage length to reduced section diameter ratio shall be 4:1 F Refer to original specification for additional information on heat treatment requirements

ASTM A 560/A 560M – 05

CASTINGS, CHROMIUM-NICKEL ALLOY This specification covers chromium-nickel alloy castings intended for heat resisting and elevated-temperature corrosion applications such as structural members, containers, supports, hangers, spacers and the like in corrosive environments up to 2000 F [1090 C].

GRADE & HEAT TREATMENT Grade A Heat Treatment And UNS 50 Cr-50 Ni As cast R20500 60 Cr-40 Ni As cast R20600 50 Cr-50 Ni-Cb As cast R20501

MECHANICAL PROPERTIES (minimum unless range given) Tensile Strength Yield Strength Elong Other Tests ksi MPa ksi MPa % B 80 550 50 340 5.0 110

760

85

590

80

550

50

345

CHEMICAL COMPOSITION, % D (maximum percent unless range given) C

Mn

Si

S

P

N

N+C

0.10 0.30 1.00 0.02 0.02 0.30

C

Fe Ti

Al

Cb Cr

Ni

48.0 52.0 bal 58.0 1.00 0.50 0.25 62.0 bal 1.4 47.0 1.00 0.50 0.25 1.7 52.0 bal 1.00 0.50 0.25

0.10 0.30 1.00 0.02 0.02 0.30 5.0 0.10 0.30 0.50 0.02 0.02 0.16 0.20

A

Heat treatment as agreed upon by manufacturer and purchaser Impact, unnotched Charpy, 50 ft-lbs [78J] minimum C Impact, unnotched Charpy, 10 ft-lbs [14J] minimum D The total of the Cr, Ni, and Cb contents must exceed 97.5% B

ASTM A 743/A 743M – 06

CASTINGS, IRON-CHROMIUM, IRON-CHROMIUM-NICKEL, CORROSION RESISTANT, FOR GENERAL APPLICATION This specification covers iron-chromium and iron-chromium-nickel-alloy castings for general corrosion-resistant application. The grades covered by this specification represent types of alloy castings suitable for broad ranges of application which are intended for a wide variety of corrosion environments.

GRADE & HEAT TREATMENT Grade A Heat Treatment and UNS CF-8 ST J92600 CG-12 ST J93001 CF-20 ST J92602 CF-8M ST J92900 CF-8C ST J92710 CF-16F ST J92701

MECHANICAL PROPERTIES (minimum unless range given) D Tensile Strength Yield Strength Elong Red A Other Tests ksi Mpa Ksi Mpa % % E E E E B 70 485 30 205 35 70

485

28

195

35

70

485

30

205

30

70

485

30

205

30

B

70

485

30

205

30

B

70

485

30

205


Mn

Si

P

S

0.08

1.50 2.00 0.04

0.04

0.12

1.50 2.00 0.04

0.04

0.20

1.50 2.00 0.04

0.04

0.08

1.50 2.00 0.04

0.04

0.08

1.50 2.00 0.04

0.04

0.16

1.50 2.00 0.17

0.04

25

39

Cr 18.0 21.0 20.0 23.0 18.0 21.0 18.0 21.0 18.0 21.0 18.0 21.0

Ni

Mo

8.0 11.0 10.0 13.0 8.0 11.0 9.0 2.0 12.0 3.0 9.0 12.0 9.0 12.0 1.50

Cb

G

Se

0.2 0.35

Cu

W

V

N

GRADE & HEAT MECHANICAL PROPERTIES TREATMENT (minimum unless range given) D Grade Red A A Tensile Strength Yield Strength Elong Heat Treatment Other Tests ksi Mpa Ksi Mpa and UNS % % CF-16Fa ST 70 485 30 205 25 CH-10 J93401 CH-20 J93402 CK-20 J94202 CE-30 J93423 CA-15 J91150 CA-15M J91151 CB-30 J91803 CC-50 J92615 CA-40 J91153 CA-40F J91154 CF-3 J92500 CF10SMnN J92972 CF-3M J92800 CF3MN J92804 CG6MMN J93790 CG-3M J92999 CG-8M J93000 CN3M J94652 CN-3MN J94651 CN-7M N08007 CN-7MS J94650 CA-6NM J91540

ST

70

485

30

205

30

70

485

30

205

ST ST

65

450

28

195

3 0 30

ST

80

550

40

275

10

NT or A

90

620

65

450

18

30

C

NT or A

90

620

65

450

18

30

C

N or A

65

450

30

205

N or A

55

380

NT or A

100

690

70

485

15

NT or A

100

690

70

485

12

C

As cast or ST

70

485

30

205

35

B

ST

85

585

42

290

30

As cast or ST As cast or ST

70 75

485 515

C

C

30 37

205 255

C

25

B

30


Mn

Si

P

S

0.16

1.50 2.00 0.04

0.20 0.40

0.10

1.50 2.00 0.04

0.04

0.20

1.50 2.00 0.04

0.04

0.20

2.00 2.00 0.04

0.04

0.30

1.50 2.00 0.04

0.04

0.15

1.00 1.50 0.04

0.04

0.15

1.00 0.65 0.040 0.040

0.30

1.00 1.50 0.04

0.04

0.50 0.20 0.40 0.20 0.40

1.00 1.50 0.04

0.04

1.00 1.50 0.04

0.04 0.20 0.40

0.03 0.10

1.50 2.00 0.04 0.04 7.0 3.50 9.0 4.50 0.060 0.030

0.03

1.50 1.50 0.04

1.00 1.50 0.04

0.04

35 0.03

ST

85

585

42

290

30

ST

75

515

35

240

25

ST

75

520

35

240

25

ST

63

435

25

170

30

ST

80

550

38

260

35

ST

62

425

25

170

35

ST

70

485

30

205

35

NT

110

755

80

550

15

B

C

35

40

1.50 1.50 0.040 0.040 4.0 0.006 6.0 1.00 0.04 0.03 0.03

1.50 1.50 0.04

0.04

0.08

1.50 1.50 0.04

0.04

0.03

2.0

0.03

0.03

2.00 1.00 0.040 0.010

0.07

0.04

0.07

1.50 1.50 0.04 2.50 1.00 3.50 0.04

0.06

1.00 1.00 0.04

0.03

1.0

0.03

0.03

Cr 18.0 21.0 22.0 26.0 22.0 26.0 23.0 27.0 26.0 30.0 11.5 14.0 11.5 14.0 18.0 21.0 26.0 30.0 11.5 14.0 11.5 14.0 17.0 21.0 16.0 18.0 17.0 21.0 17.0 21.0 20.5 23.5 18.0 21.0 18.0 21.0 20.0 22.0 20.0 22.0 19.0 22.0 18.0 20.0 11.5 14.0

Ni

Mo

Cb

Se

Cu

W

V

N

9.0 0.4 12.0 0.8 12.0 15.0 12.0 15.0 19.0 22.0 8.0 11.0 1.00 0.50 0.15 1.0 1.00

H

2.00 4.00 1.0

0.50

1.0 8.0 12.0 8.0 9.0 9.0 13.0 9.0 13.0 11.5 13.5 9.0 13.0 9.0 13.0 23.0 27.0 23.5 15.5 27.5 30.5 22.0 25.0 3.5 4.5

0.5 0.08 0.18 2.0 3.0 1.50 0.10 3.00 0.30 3.0 4.0 3.0 4.0 4.5 5.5 6.0 7.0 2.0 3.0 2.5 3.0 0.40 1.0

0.10 0.20 0.10 0.20 0.30 0.40

0.75 3.0 4.0 1.5 2.0

0.18 0.26

GRADE & HEAT TREATMENT Grade A Heat Treatment and UNS CA-6N NT J91650 F CA-28MWV QT or A J91422 CK-3MCuN ST J93254 CK-35MN ST

MECHANICAL PROPERTIES (minimum unless range given) D Tensile Strength Yield Strength Elong Red A Other Tests ksi Mpa Ksi Mpa % % 140 965 135 930 15 50

CB-6 J91804

NT

140

965

110

760

10

80

550

38

260

35

83

570

41

280

35

115

790

85

580

16

C

24

35

A


Mn

Si

P

S

Cr

Ni

Mo

10.5 6.0 0.50 1.00 0.02 0.02 12.5 8.0 0.50 11.0 0.50 0.90 1.00 1.0 0.030 0.030 12.5 1.00 1.25 19.5 17.5 6.0 0.025 1.20 1.00 0.045 0.010 20.5 19.5 7.0 22.0 20.0 6.0 0.035 2.0 1.00 0.035 0.020 24.0 22.0 6.8 15.5 3.5 0.06 1.00 1.00 0.04 0.03 17.5 5.5 0.5

Cb

Se

Cu

0.06 0.20 0.28

W

V

N

0.90 0.20 1.25 0.30 0.50 1.00 0.40

0.18 0.24 0.21 0.32

Refer to original specification for additional heat treatment information Supplementary intergranular corrosion test if specified by the customer C Supplementary requirement for hardness tests when desired by the purchaser D When ICI test bars are used in tensile tests as provided for in this specification, the gage length to reduced section diameter ratio shall be 4:1 E For low ferrite or nonmagnetic castings of this grade, the following values shall apply: tensile strength, min, 65 ksi [450 MPa]; yield point, min, 28 ksi [195 MPa] F These mechanical properties apply only when heat-treatment (1) has been used G Grade CF-8C shall have a columbium content of not less than 8 times the carbon content and not more than 1.0% - if a columbium plus tantalum alloy in the approximate Cb:Ta ratio of 3:1 is used for stabilizing this grade, the total columbium-plus-tantalum content shall not be less than nine times the carbon content and shall not exceed 1.1% H For Grade CB-30 a copper content of 0.90 to 1.20% is optional B

41

ASTM A 744/A 744M – 06

CASTINGS, IRON-CHROMIUM-NICKEL, CORROSION RESISTANT, FOR SEVERE SERVICE This specification covers iron-chromium-nickel-alloy, stainless steel castings intended for particularly corrosive applications.

GRADE & HEAT TREATMENT Grade A Heat Treatment and UNS CF-8 ST J92600 CF-8M D ST J92900 CF-8C ST J92710 CF-3 ST J92500 CF-3M D ST J92800 CG-3M ST J92999 CG-8M D ST J93000 CN-7M ST N08007 CN-7MS ST J94650 CN-3MN ST J94651 CK3MCuN ST J93254

MECHANICAL PROPERTIES (minimum unless range given) B Tensile Strength Yield Strength Elong Red A ksi

70 70 70

E

485 485 485

MPa

ksi

E

E

30 30 30

MPa

205 205 205

E

%

205

35

70

485

30

205

30

75

515

35

240

25

75

520

35

240

25

62

425

25

170

35

70

485

30

205

35

80

550

38

260

35

260

C

Mn

Ni

Cr

8.0 2.00 11.0 9.0 0.04 0.04 2.00 12.0 9.0 0.04 0.04 2.00 12.0 8.0 0.04 0.04 2.00 12.0 9.0 0.04 0.04 1.50 13.0 9.0 0.04 0.04 1.50 13.0 9.0 0.04 0.04 1.50 13.0 27.5 0.04 0.04 1.50 30.5 2.50 22.0 0.04 0.03 3.50 25.0 23.5 0.040 0.010 1.00 25.5 17.5 0.045 0.010 1.0 19.5

18.0 21.0 18.0 21.0 18.0 21.0 17.0 21.0 17.0 21.0 18.0 21.0 18.0 21.0 19.0 22.0 18.0 20.0 20.0 22.0 19.5 20.5

1.50 0.04

0.08

1.50

0.08

1.50

0.03

G

1.50

0.03

G

1.50

0.03

1.50

0.08

1.50

0.04

1.50

0.07

1.00

0.03

2.00

35 0.025 1.20

A

P

0.08 30

30

38

C

30

485

550

Other Tests

35

70

80

%

CHEMICAL COMPOSITION, % (maximum percent unless range given) S 0.04

Si

Mo

2.0 3.0

2.0 3.0 3.0 4.0 3.0 4.0 2.0 3.0 2.5 3.0 6.00 7.00 6.0 7.0

Cb

Cu

F

3.0 4.0 1.5 2.0 0.18 0.75 0.26 0.50 0.180 1.00 0.240

Refer to original specification for additional heat treatment information When ICI test bars are used in tensile tests as provided for in this specification, the gage length to reduced section diameter ratio shall be 4:1 Supplementary intergranular corrosion test if specified by the customer D For optimum tensile strength, ductility and corrosion resistance, the solution annealing temperature should be in excess of 1900 F [1040 C] E For low ferrite or nonmagnetic castings of this grade, the following values shall apply: tensile strength, min, 65 ksi [450 MPa]; yield point, min, 28 ksi [195 MPa] F Grade CF-8C shall have a columbium content of not less than 8 times the carbon content and not more than 1.0% - if a columbium-plus-tantalum alloy in the approximate Cb:Ta ration of 3:1 is used for stabilizing this grade, the total columbium-plus-tantalum content shall not be less than 9 times the carbon content sand shall not exceed 1.1% G For purposes of determining conformance with this specification, the observed or calculated value for carbon content shall be rounded to the nearest 0.01% in accordance with rounding method of Recommended Practice E29 B C

42

N

ASTM A 747/A 747M – 07

STEEL CASTINGS, STAINLESS, PRECIPITATION HARDENING This specification covers iron-chromium-nickel-copper corrosion-resistant steel castings, capable of being strengthened by precipitation hardening heat treatment.

GRADE & HEAT TREATMENT Grade and UNS CB7Cu-1 J92180

Heat Treatment H-900 H-925

A

MECHANICAL PROPERTIES (minimum unless range given) Tensile Strength Yield Strength Elong Red A ksi

170

A

MPa

1170

ksi

145

%

MPa

1000

5

%

CHEMICAL COMPOSITION, % (maximum percent unless range given) Other Tests Hardness (HBN) 375

175

1205

150

1035

5

375

H-1025

A

150

1035

140

965

9

311

H-1075

A

145

1000

115

795

9

277

H-1100

A

135

930

110

760

9

269

H-1150

A

125

860

97

670

10

269

C

Mn

0.07

0.70

0.07

0.70

P

S

Si

Ni

Cr

Cu

Cb

0.035

0.03

1.00

3.60 4.60

15.50 17.70

2.50 3.20

0.15 B 0.35

0.035

0.03

1.00

4.50 5.50

14.0 15.50

2.50 3.20

0.15 B 0.35

N

B

0.05

C

H-1150M 310 Max H-1150DBL CB7Cu-2 J92110

H-900 H-925

A

170

A

1170

145

1000

5

310 Max 375

175

1205

150

1035

5

375

H-1025

A

150

1035

140

965

9

311

H-1075

A

145

1000

115

795

9

277

H-1100

A

135

930

110

760

9

269

H-1150

A

125

860

97

670

10

269

H-1150M 310 Max H-1150DBL 310 Max A

All mechanical properties are supplementary and are not required unless stipulated by the customer, see original specification for additional information When the H900 condition is ordered, the minimum Cb shall not apply C To be determined and reported when specified by the order or contract B

43

B

0.05

C

ASTM A 890/A 890M – 07

CASTINGS, IRON-CHROMIUM-NICKEL-MOLYBDENUM CORROSION-RESISTANT, DUPLEX (AUSTENITIC/FERRITIC) FOR GENERAL APPLICATION This specification covers a group of cast duplex stainless steels (austenitic/ferritic). B

GRADE & HEAT TREATMENT Grade and UNS 1A CD4MCu J93370 1B CD4MCuN J93372 C 1C CD3MCuN J93373 2A CE8MN J93345 3A CD6MN J93371 4A CD3MN J92205 C 5A J93404 C 6A J93380

Heat Treatment

A


100

MPa

690

MECHANICAL PROPERTIES (minimum unless range given) Yield Red Elong Other Tests Strength A % ksi Mpa % 70 485 16

ST 100

690

70

485

690

65

450

655

65

450

655

65

450

620

60

415

ST

100 100

690 690

75 65

515 450

Si

Ni

Cr

Mo

Cu

1.00

0.040 0.040 1.00

4.75 6.00

24.5 26.5

1.75 2.25

2.75 3.25

1.0

0.04

4.7 6.0

24.5 26.5

1.7 2.3

2.7 3.3

0.10 0.25

24.0 26.7

2.9 3.8

1.40 1.90

0.22 0.33

0.04

1.0

0.030 0.030 1.10

5.6 6.7

0.08

1.00

0.04

8.00 22.5 11.00 25.5

3.00 4.50

0.06

1.00

0.040 0.040 1.00

4.00 6.00

24.0 27.0

1.75 2.50

0.03

1.50

0.04

0.020 1.00

4.5 6.5

21.0 23.5

2.5 3.5

0.10 0.30

0.03

1.50

0.04

0.04

0.03

1.00

0.030 0.025 1.00

6.0 8.0 6.5 8.5

24.0 26.0 24.0 26.0

4.0 5.0 3.0 4.0

0.10 0.30 0.20 0.30

0.04

1.50

18 1.00

25

A

See original specification for additional details on heat treatment Tensile requirement is a supplementary requirement, see original specification for additional details C %Cr + 3.3% Mo +16% N ≥ 40 B

44

N

0.030 1.20

25

ST ST

0.04

S

25

ST 90

0.04

P

25

ST 95

Mn

25

ST 95

C

16

ST 100

CHEMICAL COMPOSITION, % (maximum percent unless range given) W

0.10 0.30 1.00

0.5 1.0

0.15 0.25

0.5 1.0

ASTM A 990 – 08

CASTINGS, IRON-NICKEL-CHROMIUM AND NICKEL ALLOYS, SPECIALLY CONTROLLED FOR PRESSURE RETAINING PARTS FOR CORROSIVE SERVICE This specification covers iron-nickel-chromium and nickel alloy castings specially processed with restricted melt practices, weldability testing and nondestructive examination (NDE) requirements.

GRADE & HEAT TREATMENT Grade A Heat Treatment and UNS CW-2M ST

MECHANICAL PROPERTIES (minimum unless range given) Tensile Strength Yield Strength Elong Red A ksi MPa ksi MPa % % 72 495 40 275 20.0

CN3MCu

62

425

25

170

35

65

450

25

170

25

ST

M35-1

As cast


B

C

Mn

P

S

Si

Ni

Cr

15.0 0.020 1.00 0.030 0.015 0.80 Bal. 17.5 19.0 0.030 1.50 0.030 0.015 1.00 22.0 0.35

1.50 0.030 0.015 1.25

Mo

Fe

W

Cu

15.0 17.5 2.00 1.00 2.0 3.0 3.0 Bal 3.5 26.0 3.5 33.0

A

See original specification for additional details on heat treatment B See original specification for additional details on Nondestructive Examination Requirements

ISO 11972

CORROSION-RESISTANT CAST STEELS FOR GENERAL APPLICATIONS This International Standard specifies cast steels for general corrosion-resistant applications. The grades covered by this International Standard represent types of alloy steel castings suitable for broad ranges of application which are intended for a wide variety of corrosion applications.

GRADE & HEAT TREATMENT Grade and UNS GX 12 Cr 12 GX 8 CrNiMo 12 1 GX 4 CrNi 12 4 (QT 1) GX 4 CrNi 12 4 (QT 2) GX 4 CrNiMo 16 5 1 GX 2 CrNi 18 10 GX 2 CrNiN 18 10 GX 5 CrNi 19 9 GX 6 CrNiNb 19 10

Heat A Treatment A&T A &T A&T A&T A&T ST ST ST ST


Mpa 620

MECHANICAL PROPERTIES (minimum unless range given) Yield Red Other Tests Strength Elong A % Impact Ruling Thickness % ksi Mpa (J) (mm) 450 14 20 150

590

440

15

27

300

750

550

15

45

300

900

830

12

35

300

760

540

15

60

300

440

180

30

80

150

510

230

30

80

150

440

180

30

60

150

440

180

25

40

150

45


Mn

P

S

Si

Ni

0.15 0.8 0.035 0.025 0.8 1.0 0.8 0.10 0.8 0.035 0.025 0.8 1.8 3.5 0.06 1.5 0.035 0.025 1.0 5.0 3.5 0.06 1.5 0.035 0.025 1.0 5.0 4.0 0.06 0.8 0.035 0.025 0.8 6.0 9.0 0.03 1.5 0.040 0.030 1.5 12.0 9.0 0.03 1.5 0.040 0.030 1.5 12.0 8.0 0.07 1.5 0.040 0.030 1.5 11.0 9.0 0.08 1.5 0.040 0.030 1.5 12.0

Cr Mo 11.5 13.5 11.5 13.0 11.5 13.0 11.5 13.0 15.0 17.0 17.0 19.0 17.0 19.0 18.0 21.0 18.0 21.0

N

Nb

0.5 0.2 0.5 1.0 1.0 0.7 1.5 0.10 0.20 8xC 1.00

Cu

GRADE & HEAT TREATMENT Grade and UNS GX 2 CrNiMo 19 11 2 GX 2 CrNiMoN 19 11 2 GX 5 CrNiMo 19 11 2 GX 6 CrNiMoNb 19 11 2 GX 2 CrNiMo 19 11 3 GX 2 CrNiMoN 19 11 3 GX 5 CrNiMo 19 11 3 GX 2 CrNiCuMoN 26 5 3 3 GX 2 CrNiMoN 26 5 3 A

Heat A Treatment ST ST ST ST ST ST ST ST ST


Mpa 440

MECHANICAL PROPERTIES (minimum unless range given) Yield Red Other Tests Strength Elong A % Impact Ruling Thickness % ksi Mpa (J) (mm) 180 30 80 150

510

230

30

80

150

440

180

30

60

150

440

180

25

40

150

440

180

30

80

150

510

230

30

80

150

440

180

30

60

150

650

450

18

50

150

650

450

18

50

150


Mn

P

S

Si

Ni

9.0 0.03 1.5 0.040 0.030 1.5 12.0 9.0 0.03 1.5 0.040 0.030 1.5 12.0 9.0 0.07 1.5 0.040 0.030 1.5 12.0 9.0 0.08 1.5 0.040 0.030 1.5 12.0 9.0 0.03 1.5 0.040 0.030 1.5 12.0 9.0 0.03 1.5 0.040 0.030 1.5 12.0 9.0 0.07 1.5 0.040 0.030 1.5 12.0 4.5 0.03 1.5 0.035 0.025 1.0 6.5 4.5 0.03 1.5 0.035 0.025 1.0 6.5

Cr Mo 17.0 20.0 17.0 20.0 17.0 20.0 17.0 20.0 17.0 20.0 17.0 20.0 17.0 20.0 25.0 27.0 25.0 27.0

2.0 2.5 2.0 2.5 2.0 2.5 2.0 2.5 3.0 3.5 3.0 3.5 3.0 3.5 2.5 3.5 2.5 3.5

N

Nb

Cu

0.10 0.20 8xC 1.00 0.10 0.20 0.20 0.12 0.25 0.12 0.25

2.5 3.5

See original specifications for additional information

ISO 11973

HEAT-RESISTANT CAST STEELS FOR GENERAL PURPOSES This International Standard covers cast steels for heat resistant service.

GRADE & HEAT TREATMENT Grade and UNS GX 30 CrSi 7 GX 40 CrSi 13 GX 40 CrSi 17 GX 40 CrSi 24 GX 40 CrSi 28 GX 130 CrSi 29

MECHANICAL PROPERTIES (minimum unless range given) Tensile Yield Other Tests Strength Strength Red Heat Elong A C Mn Use Treatment % Hardness ksi MPa ksi MPa % Temp. (HBN) C (C) A or as 0.20 0.50 cast 750 0.35 1.00 0.30 0.50 A B 300 850 0.50 1.00 0.30 0.50 A B 300 900 0.50 1.00 0.30 0.50 A B 300 1050 0.50 1.00 0.30 0.50 A B 320 1100 0.50 1.00 1.20 0.50 A B 400 1100 1.40 1.00

46

CHEMICAL COMPOSITION, % (maximum percent unless range given) P

S

Si

1.00 0.040 0.040 2.50 1.00 0.040 0.030 2.50 1.00 0.040 0.030 2.50 1.00 0.040 0.030 2.50 1.00 0.040 0.030 2.50 1.00 0.040 0.030 2.50

Ni

Cr

6.00 0.50 8.00 12.00 1.00 14.00 16.00 1.00 19.00 23.00 1.00 26.00 27.00 1.00 30.00 27.00 1.00 30.00

Mo

0.50 0.50 0.50 0.50 0.50 0.50

Nb

Co

W

N

N+C W

Fe


MECHANICAL PROPERTIES CHEMICAL COMPOSITION, % (minimum unless range given) (maximum percent unless range given) Tensile Yield Other Tests Strength Strength Red Grade Heat Elong A C Mn P S Si Ni Cr Mo Nb Co W N N+C W Fe Use and UNS Treatment % Hardness ksi MPa ksi MPa % Temp. (HBN) C (C) GX 25 CrNiSi 18-9 450 230 15 0.15 1.00 8.00 17.00 As cast 900 0.35 2.00 0.040 0.030 2.50 10.00 19.00 0.50 GX 25 CrNiSi 20-14 450 230 10 0.15 1.00 13.00 19.00 As cast 900 0.35 2.00 0.040 0.030 2.50 15.00 21.00 0.50 GX 40 CrNiSi 22-10 450 230 8 0.30 1.00 9.00 21.00 As cast 950 0.50 2.00 0.040 0.030 2.50 11.00 23.00 0.50 GX 40 CrNiSiNb 24-24 400 220 4 0.25 1.00 23.00 23.00 1.20 As cast 1050 0.50 2.00 0.040 0.030 2.50 25.00 25.00 0.50 1.80 GX 40 CrNiSi 25-12 450 220 6 0.30 1.00 11.00 24.00 As cast 1050 0.50 2.00 0.040 0.030 2.50 14.00 27.00 0.50 GX 40 CrNiSi 25-20 450 220 6 0.30 1.00 19.00 24.00 As cast 1100 0.50 2.00 0.040 0.030 2.50 22.00 27.00 0.50 GX 40 CrNiSi 27-4 400 250 3 0.30 1.00 3.00 25.00 As cast 400 Max 1100 0.50 1.50 0.040 0.030 2.50 6.00 28.00 0.50 GX 40 NiCrCo 20-20-20 400 320 6 0.35 18.00 19.00 2.50 18.00 2.0 As cast 1150 0.60 2.00 0.040 0.030 1.00 22.00 22.00 3.00 22.00 3.0 GX 10 NiCrNb 31-20 440 170 20 0.05 30.00 19.00 0.80 As cast 1000 0.12 1.20 0.040 0.030 1.20 34.00 23.00 0.50 1.50 GX 40 NiCrSi 35-17 420 220 6 0.30 1.00 34.00 16.00 As cast 980 0.50 2.00 0.040 0.030 2.50 36.00 18.00 0.50 GX 40 NiCrSi 35-26 440 220 6 0.30 1.00 33.00 24.00 As cast 1050 0.50 2.00 0.040 0.030 2.50 36.00 27.00 0.50 GX 40 NiCrSiNb 35-26 440 220 4 0.30 1.00 33.00 24.00 0.80 As cast 1050 0.50 2.00 0.040 0.030 2.50 36.00 27.00 0.50 1.80 GX 40 NiCrSi 38-19 420 220 6 0.30 1.00 36.00 18.00 As cast 1050 0.50 2.00 0.040 0.030 2.50 39.00 21.00 0.50 GX 40 NiCrSiNb 38-19 420 220 4 0.30 1.00 36.00 18.00 1.20 As cast 1000 0.50 2.00 0.040 0.030 2.50 39.00 21.00 0.50 1.80 GX 45 NiCrWSi 48-28-5 400 220 3 0.35 1.00 47.00 27.00 4.00 As cast 1200 0.55 1.50 0.040 0.030 2.50 50.00 30.00 6.00 GX 10 NiCrNb 50-50 540 230 8 47.00 1.4 As cast 1050 0.10 0.50 0.020 0.020 0.50 bal. 52.00 0.50 1.7 0.16 0.20 GX 50 NiCr 52-19 440 220 5 0.40 0.50 50.00 16.00 As cast 1100 0.60 1.50 0.040 0.030 2.00 55.00 21.00 0.50 GX 50 NiCr 65-15 400 200 3 0.35 64.00 13.00 As cast 1100 0.65 1.30 0.040 0.030 2.00 69.00 19.00 GX 45 NiCrCoW 35-25-15-5 480 270 5 0.44 1.00 33.00 24.00 14.0 4.0 As cast 1200 0.48 2.00 0.040 0.030 2.00 37.00 26.00 16.0 6.0 GX 30 CoCr 50-28 25.00 48.0 A A A A As cast 1200 0.50 1.00 0.040 0.030 1.00 1.00 30.00 0.50 52.0 20.0 A Properties as agreed upon by manufacturer and purchaser B Maximum hardness in annealed condition – castings may also be supplied in the “as cast” condition, in which case hardness limits will not apply

47

C

Maximum use temperature depends upon the actual use conditions and these values are being given only to aid the user; these are given for oxidising environments, the actual alloy composition will also affect performance

ISO 12725

NICKEL AND NICKEL ALLOY CASTINGS This International Standard specifies requirements for nickel and nickel alloy castings. The grades covered represent types of alloys suitable for a broad range of application in a wide variety of corrosive and high temperature environments.

GRADE & HEAT TREATMENT Grade and UNS C-Ni99, HC C-NiCu30Si C-NiCu30 C-NiCu30Si3 C-NiCu30Nb2Si2 C-NiMo31 C-NiMo30Fe5 -NiCr22Fe20Mo7Cu2 C-NiCr22Mo9Nb4 C-NiCr16Mo16 C-NiMo17Cr16Fe6W4 C-NiCr21Mo14Fe4W3 C-NiCr18Mo18 C-NiCr15Fe C-NiFe30Cr20Mo3CuNb C-NiSi9Cu3 A B

Heat A Treatment As cast As cast As cast As cast As cast WQ WQ WQ WQ WQ WQ WQ WQ WQ AC AC

MECHANICAL PROPERTIES CHEMICAL COMPOSITION, % B (minimum unless range given) (maximum percent unless range given) Tensile Yield Red Other Tests Elong C Co Cr Cu Fe Mn Mo Ni P S Si W Strength Strength A Hardness % % (HBN) ksi MPa ksi MPa 345 125 10 95.0 545 1.00 1.25 3.0 1.50 0.030 0.030 2.00 450 205 25 26.0 650 0.35 33.0 3.5 1.50 bal. 0.030 0.030 2.00 450 170 25 26.0 0.35 33.0 3.5 1.50 bal. 0.030 0.030 1.25 690 415 10 27.0 2.7 890 0.30 33.0 3.5 1.50 bal. 0.030 0.030 3.7 450 225 25 26.0 1.0 0.30 33.0 .5 1.50 bal. 0.030 0.030 2.0 525 275 6 30.0 725 0.03 1.0 3.0 1.00 33.0 bal. 0.030 0.030 1.00 525 275 20 4.0 26.0 725 0.05 1.0 6.0 1.00 33.0 bal. 0.030 0.030 1.00 550 220 30 21.5 1.5 18.0 6.0 750 0.02 5.0 23.5 2.5 21.0 1.00 8.0 bal. 0.025 0.030 1.00 1.50 485 275 25 20.0 8.0 685 0.06 23.0 5.0 1.00 10.0 bal. 0.030 0.030 1.00 495 275 20 15.0 15.0 695 0.02 17.5 2.0 1.00 17.5 bal. 0.030 0.030 0.80 1.00 495 275 4 15.5 4.5 16.0 3.8 695 0.06 17.5 7.5 1.00 18.0 bal. 0.030 0.030 1.00 5.3 550 280 30 20.0 2.0 12.5 2.5 0.02 22.5 6.0 1.00 14.5 bal. 0.025 0.025 0.80 3.5 495 275 25 17.0 17.0 695 0.03 20.0 3.0 1.00 20.0 bal. 0.030 0.030 1.00 485 195 30 14.0 685 0.40 17.0 11.0 1.50 bal. 0.030 0.030 3.00 450 170 25 19.5 1.5 28.0 2.5 0.75 650 0.05 23.5 3.0 32.0 1.00 3.5 bal. 0.030 0.030 1.20 300 2.4 8.5 0.12 1.0 4.0 1.50 bal. 0.030 0.030 10.0

See original specification for full details Single values are maximum limits, except for nickel for which single values are minimum.

48

Nb

V

Nb+Ta

0.5 0.5 1.0 3.0 0.20 0.60 0.5 3.2 4.5 0.20 0.40 0.35

0.70 1.00

ISO 19960

CAST STEELS AND ALLOYS WITH SPECIAL PHYSICAL PROPERTIES The cast steel and alloy grades covered by this international standard are used in applications which require low linear thermal expansion, or low ferromagnetic responses, or low galling properties.

GRADE & HEAT TREATMENT Grade and UNS GX12CrNi18-11 GX2CrNiN18-13 GX2CrNiMoN18-14 GX2CrNiN19-11 GX3CrNiMnSi17-9-8

ST

GX4CrNiMnN22-12-5

GX3NiCo29-17 GX3Ni36 GX3NiS36 G-NiCr13SnBiMo

MIL-C-24707/3

580

290

24

580

290

24


ST + T

570 800 425

315

20

250

15

ST + T ST + T

260

175

20

260

175

20

As cast

P

S

Cr

0.05

.50

0.60 0.030 0.020 0.25

0.05

.50

0.50 0.030 0.020 0.25

0.05

.50

0.05

.50

0.05

.50

0.50 0.030 0.020 0.25 0.10 0.50 0.030 0.20 0.25 11.0 1.50 0.030 0.030 14.0

0.030 0.030

65

ST + T

Mn

0.030

0.030

0.06

ST

Si

16.5 1.50 2.00 0.045 0.030 18.5 16.5 1.50 2.00 0.035 0.020 18.5 16.5 1.50 2.00 0.035 0.020 18.5 18.0 1.50 2.00 0.035 0.020 20.0 3.5 7.0 16.0 4.5 9.0 0.045 0.030 18.0 4.0 20.5 1.00 6.0 0.040 0.030 23.5 4.0 20.0 1.00 6.0 0.025 0.010 21.5

0.15

0.05

ST

GX2CrNiMnMoNNb21-16-5-3 GX3NiCo32

MECHANICAL PROPERTIES (minimum unless range given) Tensile Yield Red Heat Elong Charpy Strength Strength A Treatment ksi MPa ksi MPa % J. min % 440 195 20 80 ST 590 440 210 30 115 ST 640 490 240 30 80 ST 690 440 180 30 ST

Mo

Ni

10.0 0.75 12.0 12.0 1.00 14.0 2.50 13.0 3.00 15.0 10.0 1.00 12.0 8.0 1.00 9.0 1.50 11.5 3.00 13.5 3.0 15.0 3.5 17.0 30.5 1.00 33.5 28.0 1.00 30.0 35.0 1.00 37.0 35.0 1.00 37.0 2.00 3.50 Bal.

N

Co

Cu

Nb

V

Al Fe Bi Sn

0.50 0.10 0.20 0.15 0.25 0.10 0.20 0.08 0.18 0.20 0.40 0.20 0.35

0.50 0.50 0.50 0.50 0.10 0.10 0.50 0.30 0.30 0.50 0.25 4.0 6.5 0.50 16.0 18.0 0.50

0.10

0.50 0.50 0.50

CASTINGS, FERROUS, CORROSION-RESISTANT, AUSTENITIC, CHROMIUM-NICKEL This specification covers austenitic chromium-nickel alloy castings for corrosion-resistant and low magnetic permeability applications. PREVIOUS SPECIFICATION

REPLACEMENT SPECIFICATION MIL-C-24707/3 ASTM specification (grade)

MIL specification (class) MIL-S-17509 (I) MIL-S-17509 (II) MIL-S-17509 (III) MIL-S-867 (I) MIL-S-867 (II) MIL-S-867 (III)

A 744 (CF-8) A 744 (CF-8C) A 744 (CF-8M) A 744 (CF-8) A 744 (CF-8C) A 744 (CF-8M)

49

3.0 3.0 2.0 5.0 5.0

Additional notes for specification are as follows; see original military specification booklet for further information, including Quality Assurance Provisions. Two different levels may be specified; level I has no magnetic restrictions and level II has low relative magnetic permeability. For all grades, supplementary requirements SZ1 (intergranular corrosion test) and SZ2 (tension test) of ASTM A 744 shall be mandatory. When type II is specified, the relative magnetic permeability of the castings shall not exceed 1.3 for first article and 1.6 for quality conformance tests; unless otherwise specified, the field strength shall be 0.5 oersteds for first article testing. Heat treat casting per ASTM A 744 except the minimum temperature shall be 1950 F. After all cleaning and machining, the casting shall be passivated in accordance with QQ-P-35.

MIL-C-24707/6

CASTINGS, FERROUS, CHROMIUM STEEL, FOR PRESSURE-CONTAINING PARTS SUITABLE FOR HIGHTEMPERATURE SERVICE This specification covers 12% chromium steel castings for high temperatures and for impact at low temperatures. PREVIOUS SPECIFICATION

REPLACEMENT SPECIFICATION MIL-C-24707/6 ASTM specification (grade)

MIL specification (class) MIL-S-16993 (1) MIL-S-16993 (2)

A 217 (CA-15) A 487 (CA-15M, class A)

Additional notes for specification are as follows; see original military specification booklet for further information, including Quality Assurance Provisions. ASTM A 757 grade E3N castings are intended for use where either CA-15 or CA-15M is used; grade E3N has better weldability, corrosion and erosion resistance, low temperature properties such as notch toughness, and improved soundness and casting characteristics. CA-15M castings shall be normalized and tempered only with a tempering temperature not less than 1100 F; a liquid quench shall not be used without the permission of the Command or agency concerned.

50

SUMMARY OF MATERIAL SPECIFICATIONS FOR CENTRIFUGALLY CAST STEELS

Below is a list of centrifugally cast steel specifications, with summary details on the following pages. Note that the values given in the summary of the specifications are stated with either U.S. Conventional Units (USCS) or Metric (SI) units, and are to be regarded separately. Units given in brackets are SI units. The values stated in each system are not exact equivalents (soft conversion); therefore, each system must be used independently of the other. Combining values from the two systems, by using conversion equations (hard conversion), may result in nonconformance with the specification. Also note that the values in the table are given in a minimum over maximum format. This means that if the value is a minimum it will be listed in the upper portion of the specification’s table row and in the lower portion of the row if it is a maximum value. Finally, note that tables and their footnotes may be split across two or more pages. ASTM A 426 – 08 ASTM A 451 – 06 ASTM A 608 – 06 ASTM A 660 – 05 ASTM A 872 – 07 ISO 13583-2

Centrifugally Cast Ferritic Alloy Steel Pipe for High-Temperature Service Centrifugally Cast Austenitic Steel Pipe for High-Temperature Service Centrifugally Cast Iron-Chromium-Nickel High-Alloy Tubing for Pressure Application at High Temperatures Centrifugally Cast Carbon Steel Pipe for High Temperature Service Centrifugally Cast Ferritic/Austenitic Stainless Steel Pipe for Corrosive Environments Centrifugally Cast Tube

51

ASTM A 426 – 08

CENTRIFUGALLY CAST FERRITIC ALLOY STEEL PIPE FOR HIGH-TEMPERATURE SERVICE This specification covers centrifugally cast alloy steel pipe intended for use in high-temperature, high-pressure service.

GRADE & HEAT TREATMENT Grade Heat A and UNS Treatment CP1 NT, QT J12521 CP2 NT, QT J11547 CP5 NT, QT J42045 CP5b NT, QT J51545 CP9 NT, QT J82090 CP91 NT, QT 84090 CP11 NT, QT J12072 CP12 NT, QT J11562 CP15 NT, QT J11522 CP21 NT, QT J31545 CP22 NT, QT J21890 CPCA15 NT, QT J91150/71

MECHANICAL PROPERTIES (minimum unless range given) B Tensile Strength Yield Strength Elong Red A Other Tests C % % Hardness (HBN) ksi MPa ksi MPa 65 450 35 240 24 35 201 60 415 30 205 22 35 201 90 620 60 415 18 35 225 60 415 30 205 22 35 225 90 620 60 415 18 35 225 85 585 60 415 18 45 110 760 225 70 485 40 275 20 35 201 60 415 30 205 22 35 201 60 415 30 205 22 35 201 60 415 30 205 22 35 201 70 485 40 275 20 35 201 90 620 65 450 18 30 225


Mn

0.25 0.10 0.20 0.20 0.15 0.20 0.08 0.12 0.05 0.20 0.05 0.15 0.15 0.05 0.15 0.05 0.15 0.15

0.30 0.80 0.30 0.61 0.30 0.70 0.30 0.60 0.30 0.65 0.30 0.60 0.30 0.80 0.30 0.61 0.30 0.60 0.30 0.60 0.30 0.70

P

S

Si

Cr

0.10 0.040 0.045 0.50 0.10 0.50 0.040 0.045 0.50 0.81 4.00 0.040 0.045 0.75 6.50 1.00 4.00 0.040 0.045 2.00 6.00 0.25 8.0 0.040 0.045 1.00 10.0 0.20 8.0 0.030 0.010 0.50 9.5 1.00 0.040 0.045 0.60 1.50 0.80 0.040 0.045 0.50 1.25 0.15 0.040 0.045 1.65 2.65 0.040 0.045 0.50 3.35 2.00 0.040 0.045 0.60 2.75 11.5 1.00 0.040 0.040 1.50 14.0

A

Minimum tempering temperature given Hydrostatic test – see original specification for further details C Elongation in 2 in. (50mm) using a standard round specimen, in either transverse or longitudinal direction. B

52

Mo 0.44 0.65 0.44 0.65 0.45 0.65 0.45 0.65 0.90 1.20 0.85 1.05 0.44 0.65 0.44 0.65 0.44 0.65 0.80 1.06 0.90 1.20 0.50 Max

Ni

Cb

0.40

0.060 0.10

N

0.030 0.070

V

Al

Ti

Zr

0.18 0.25

0.02

0.01

0.01

ASTM A 451 – 93

CENTRIFUGALLY CAST AUSTENITIC STEEL PIPE FOR HIGH-TEMPERATURE SERVICE This specification covers austenitic alloy steel pipe for use in high-temperature, corrosive, or nuclear pressure service.

GRADE & HEAT TREATMENT Grade Heat TreatmentB And UNS CPF3 ST J92500 A CPF3A ST J92500 CPF3M ST J92800 CPF8 ST J92600 A CPF8A ST J92600 CPF8M ST J92900 E CPF10MC ST CPH10 J93402 E CPF8C J92710 CPF8C D (Ta max) CPH8 J93400 CPK20 J94202 CPH20 J93402 CPE 20N

ST ST ST ST ST ST ST

Tensile Strength ksi MPa 70 485

MECHANICAL PROPERTIES (minimum unless range given) Yield Strength Elong Red A % % ksi MPa 30 205 35

77

535

35

240

35

70

485

30

205

30

70

485

30

205

35

77

535

35

240

35

70

485

30

205

30.0

70

485

30

205

20.0

70

485

30

205

30.0

70

485

30

205

30.0

CHEMICAL COMPOSITION, % (maximum percent unless range given) Other Tests C Hydrostatic Test

C

485

30

205

30.0

65

448

28

195

30.0

65

448

28

195

30.0

70

485

30

205

30.0

80

550

40

275

30.0

S

Si

1.50 0.040

0.040

2.00

0.03

1.50 0.040

0.040

2.00

0.03

1.50 0.040

0.040

1.50

0.08

1.50 0.040

0.040

2.00

0.08

1.50 0.040

0.040

2.00

0.08

1.50 0.040

0.040

1.50

0.10

1.50 0.040

0.040

1.50

1.50 0.040

0.040

2.00

0.08

1.50 0.040

0.040

2.00

0.08

1.50 0.040

0.040

2.00

0.08

1.50 0.040

0.040

1.5

0.20

1.50 0.040

0.040

1.75

1.50 0.040

0.040

2.00

1.50 0.040

0.040

1.50

0.20 0.20

A

P

0.03

0.10 70

Mn

F

F

Ni

Cr

8.0 12.0 8.0 12.0 9.0 13.0 8.0 11.0 8.0 11.0 9.0 12.0 13.0 16.0 12.0 15.0 9.0 12.0 9.0 12.0 12.0 15.0 19.0 22.0 12.0 15.0 8.0 11.0

17.0 21.0 17.0 21.0 17.0 21.0 18.0 21.0 18.0 21.0 18.0 21.0 15.0 18.0 22.0 26.0 28.0 21.0 18.0 21.0 22.0 26.0 23.0 27.0 22.0 26.0 23.0 26.0

Mo

Cb

Ta

N

2.0 3.0

2.0 3.0 1.75 10xC Min 2.25 1.2 Max 8xC Min 1.0 Max 8xC Min 1.0 Max

0.10

0.08 0.20

The properties shown are obtained by adjusting the composition within the limits shown in the table to obtain a ferrite-austentite ratio that will result in the higher ultimate yield strengths indicated – a lowering of impact values may develop in these materials when exposed to service temperature above 800 F B The pipe shall receive a solution treatment, ST, at the temperature shown with holding time 2 h/in of thickness [50.8 mm] for CPF10MC, CPF8C, and CPF8C (Ta max), and 1 h/in of thickness for all others, followed by quenching C Hydrostatic test – see original specification for further details D No designation as yet assigned by ASTM or SFSA E Grades CPF10MC and CPF8C have a columbium plus tantalum content maximum of 1.35% F By agreement between the manufacturer and the purchaser, the carbon content of Grade CPH20 may be restricted to 0.10% maximum – when so agreed, the grade designation shall be CPH10

53

ASTM A 608 – 06

CENTRIFUGALLY CAST IRON-CHROMIUM-NICKEL HIGH-ALLOY TUBING FOR PRESSURE APPLICATION AT HIGH TEMPERATURES This specification covers iron-chromium-nickel, high-alloy tubes made by the centrifugal casting process intended for use under pressure at high temperatures. GRADE & HEAT TREATMENT

Grade and UNS HC 30 J92613 HD 50 J92615 HE 35 J93413 HF 30 J92803 HH 30 J93513 A HH 33 J93633 HI 35 J94613 HK 30 J94203 HK 40 J94204 HL 30 N08613 HL 40 N08614 HN 40 J94214 HT 50 N08050 HU 50 N08005 HW 50 N08006 HX 50 N06050 A


Heat Treatment As cast As cast As cast As cast As cast As cast As cast As cast As cast As cast As cast As cast As cast As cast As cast As cast

C 0.25 0.35 0.45 0.55 0.30 0.40 0.25 0.35 0.25 0.35 0.28 0.38 0.30 0.40 0.25 0.35 0.35 0.45 0.25 0.35 0.35 0.45 0.35 0.45 0.40 0.60 0.40 0.60 0.40 0.60 0.40 0.60

Mn

P

S

0.5 1.0

0.04

0.04

1.50

0.04

0.04

1.50

0.04

0.04

1.50

0.04

0.04

1.50

0.04

0.04

1.50

0.04

0.04

1.50

0.04

0.04

1.50

0.04

0.04

1.50

0.04

0.04

1.50

0.04

0.04

1.50

0.04

0.04

1.50

0.04

0.04

1.50

0.04

0.04

1.50

0.04

0.04

1.50

0.04

0.04

1.50

0.04

0.04

Manufacturing control should ensure that this composition contain a minimal amount of ferrite

54

Si 0.50 2.00 0.50 2.00 0.50 2.00 0.50 2.00 0.50 2.00 0.50 2.00 0.50 2.00 0.50 2.00 0.50 2.00 0.50 2.00 0.50 2.00 0.50 2.00 0.50 2.00 0.50 2.00 0.50 2.00 0.50 2.00

Ni 4.0 4 7 8 11 9 12 11 14 12 14 14 18 19 22 19 22 18 22 18 22 23 27 33 37 37 41 58 62 64 68

Cr 26 30 26 30 26 30 19 23 24 28 24 26 26 30 23 27 23 27 28 32 28 32 19 23 15 19 17 21 10 14 15 19

Mo 0.50 0.50 0.50 0.50 0.50 0.50 0.50 0.50 0.50 0.50 0.50 0.50 0.50 0.50 0.50 0.50

ASTM A 660 – 05

CENTRIFUGALLY CAST CARBON STEEL PIPE FOR HIGH TEMPERATURE SERVICE This specification covers carbon steel pipe made by the centrifugal casting process intended for use in high-temperature, highpressure service. Pipe ordered under this specification shall be suitable for fusion welding, bending, and other forming operations.

GRADE & HEAT TREATMENT Grade and UNS WCA J02504 WCB J03003 WCC J02505

Heat Treatment

Tensile Strength

A

ksi

60

MPa

414

MECHANICAL PROPERTIES (minimum unless range given) Yield Strength Elong Red A ksi MPa % % 30 207 24 35


B

C 0.25

70

483

36

248

22

35

70

483

40

276

22

35

C

0.30 0.25

Mn 0.70

C

1.00 D

1.20

D

P

S

Si

0.035

0.035

0.60

0.035

0.035

0.60

0.035

0.035

0.60

A

Heat treatment per design and chemical composition Hydrostatic and flattening tests – see original specification for further details C For each reduction of 0.01% below the specified maximum carbon content, an increase of 0.04% manganese above the specified maximum will be permitted to a maximum of 1.10% D For each reduction of 0.01% below the specified maximum carbon content, an increase of 0.04% manganese above the specified maximum will be permitted to a maximum of 1.40% B

ASTM A 872 – 07

CENTRIFUGALLY CAST FERRITIC/AUSTENITIC STAINLESS STEEL PIPE FOR CORROSIVE ENVIRONMENTS This specification covers centrifugally cast ferritic/austenitic steel pipe intended for general corrosive service. These steels are susceptible to embrittlement if used for prolonged periods at elevated temperatures.

GRADE & HEAT TREATMENT Grade and UNS J93183 J93550 J94300

Heat Treatment


WQ 1920-2100F 90 [1050-1150C] WQ 1920-2100F 90 [1050-1150C] WQ 1900 minimum 110

MPa

620 620 760

MECHANICAL PROPERTIES (minimum unless range given) Red Other Tests Yield Strength Elong C A % Hardness (HBN / HRC) ksi MPa % 65 450 25 290 / 30.5 0.030 65 450 20 297 / 31.5 0.030 70 480 20 0.04

55

CHEMICAL COMPOSITION, % (maximum percent unless range given) Mn

P

S

Si

2.0

0.040

0.030

2.0

2.0 0.50 1.50

0.040 0.04

0.030 0.04

2.0 1.10

Ni

Cr

4.00 6.00 5.00 8.00 4.5 6.0

20.0 23.0 23.0 26.0 24.5 26.5

Mo 2.00 4.00 2.00 4.00 2.5 4.0

N

Cu

0.08 0.25

0.08 0.25

1.00 0.18 0.26

1.00 1.3 3.0

Co 0.50 1.50 0.50 1.50

ISO 13583-2

CENTRIFUGALLY CAST TUBE MECHANICAL PROPERTIES (minimum unless range given)

GRADE Grade and UNS GX30CrNiSi19-9

Tensile

Yield

Mpa

Mpa

450

230

Elong % 15


100 hr. rupture °C 800

MPa 47

GX40CrNiSi25-12

450

230

10

900

34

GX42CrNiSi25-20

450

220

8

900

40

GX30CrNiSiNb24-24

450

220

10

900

48

GX12NiCrSi32-21

440

170

20

800

70

GX40NiCrSi38-18

420

220

6

900

34

GX12NiCrSiNb35-25

440

175

20

800

70

GX42NiCrSiNb35-25

450

220

8

950

40

GX43NiCrSiNb35-25

450

220

8

950

40

GX42NiCrSi35-25

450

220

8

950

42

GX42NiCrWSi35-25-5 GX42NiCrSiNbTi 45-35 GX45NiCrCoW35-25-15-5

450 450 450

220 250 250

4 5 5

950 1050 950

35 21 40

GX48NiCrWSi48-28-5

400

220

5

1050

20

GX48NiCrWCo48-28-5-3

400

220

5

1050

20

GX8NiCrNb50-50 A

550

250

8

900

C

Si

Mn

0.25 0.35 0.35 0.45 0.38 0.45 0.25 0.35 0.08 0.15 0.35 0.45 0.08 0.15 0.38 0.45 0.38 0.48 0.38 0.48 0.38 0.48 0.38 0.48 0.40 0.50 0.40 0.55 0.40 0.55

1.30 1.80 1.00 2.00 1.00 2.00 0.70 2.00 0.50 1.50 1.30 2.00 0.50 1.50 0.50 1.50 1.50 2.50 1.00 2.00 1.00 2.00 1.00 2.00 1.00 2.00 1.00 1.75 1.00 1.75

0.50 1.50 0.50 1.50 0.50 1.50 0.50 1.50 0.50 1.50 0.50 1.50 0.50 1.50 0.50 1.50 0.50 1.50 0.50 1.50 0.50 1.50 0.50 1.50 0.50 1.50 0.50 1.50 0.50 1.50

0.1

0.5

0.50

P

S

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.02

0.02

40

Other micro alloying elements can be substituted for titanium. The total micro alloying elements shall be 0.06% min.

56

Cr

Ni

18.0 20.0 24.0 26.0 24.0 26.0 23.0 25.0 19.0 22.0 17.0 19.0 24.0 27.0 24.0 27.0 24.0 27.0 24.0 27.0 24.0 27.0 33.0 36.0 24.0 26.0 27.0 29.0 27.0 29.0 47.0 52.0

18.0 20.0 24.0 26.0 24.0 26.0 23.0 25.0 32.0 33.0 36.0 39.0 34.0 37.0 34.0 37.0 34.0 37.0 34.0 37.0 34.0 37.0 44.0 47.0 33.0 37.0 47.0 49.0 47.0 49.0 Bal.

Mo

Nb

W

Co

Ti

N

C+N

Fe

0.5 0.5 0.5 0.5 0.5

1.20 1.80 0.60 1.30

0.5 0.5 0.5 0.5 0.5

0.60 1.30 0.60 1.25 0.60 1.80 0.60 1.80 4.00 6.00

0.5 0.5

0.50 1.50

0.06 A Min. 4.00 6.00 4.00 6.00 4.00 6.00

0.5 0.5 0.5 0.5

0.06 A Min.

1.40 1.70

14.0 16.0 2.50 3.50 0.16

0.20

1.0

SUMMARY OF STANDARD TEST METHODS FOR STEEL CASTINGS

Overview Testing is required to ensure that the product will perform safely and economically in service. Excessive testing and overly stringent requirements increase the cost of the product without increasing value. On the other hand, insufficient testing or overly lax requirements are meaningless. Therefore, it becomes the task of the customer to decide what tests and requirements are necessary for his or her application. Mechanical properties and chemical compositional limits are generally the subject of ASTM material specifications. These must be controlled and tested in products ordered to those specifications. Consult the latest revisions of the ASTM Standards referenced in this document for more information.

Mechanical Testing Background Mechanical testing is generally carried out in accordance with methods described in ASTM A 370, “Standard Test Methods and Definitions for Mechanical Testing of Steel Products”. These methods cover procedures and definitions for the mechanical testing of wrought and cast steel products. The various mechanical tests herein described are used to determine properties required in the product specifications. Variations in testing methods are to be avoided and standard methods of testing are to be followed to obtain reproducible and comparable results. The test methods most often used in steel castings include tension testing, hardness testing, and impact testing. The mechanical properties are obtained from test bars and represent the quality of the steel from which the castings have been poured. The properties are not identical with the properties of the castings, which are affected by solidification rates and cooling rates during heat treating, which in turn are influenced by casting thickness, size, and shape. Tension Testing The tension test is the most uniformly applied test used to verify the mechanical performance of the material. The test results include tensile strength, yield strength, elongation and reduction in area. The strength measurements are useful in determining the load bearing capabilities of the material. Ductility measurements give an indication of the ability of the material to undergo deformation. The tension test is used to verify that the mechanical performance of the material is consistent. Evaluating performance in service environments may require information of other material properties such as fracture toughness, fatigue, creep-rupture, etc. Hardness Testing Hardness testing is used as a quick estimation of strength and/or wear resistance. It is particularly useful in the control of heat treatment for carbon and low to medium alloy steels. The most commonly used method for determining hardness in steel castings is the Brinell Test. The Rockwell test uses a much smaller probe and when used on cast steels is subject to variations. Converting numbers must be done with care because the conversions from Brinell to Rockwell is not exact and varies somewhat depending on the actual alloy tested. Stainless cast steels, excluding martensitic grades, are treated for corrosion resistance, not to develop strength and the hardness does not relate to heat treatment. Impact Testing Impact testing gives the amount of energy absorbed by a material. A sample of the material is hit with a hammer that has a known energy. The difference in energy the hammer has after striking the material is the impact strength of the material. This provides a useful measure of toughness or resistance to sudden failure. For low temperature service this test becomes increasingly important because most steels become less tough as the 57

temperature decreases. Impact testing is an ASTM requirement in specifications for material used in low temperature service. The Charpy V-notch is the most commonly applied method.

Nondestructive Examination Background Nondestructive examination testing is done to verify the mechanical integrity or soundness of the steel casting. It can be separated in to surface examination methods which include visual, liquid penetrant, and magnetic particle and subsurface or internal examination methods which include radiography and ultrasonics. Not only must a test method be chosen, but also an acceptance criterion must be applied. Acceptance criteria should be related to the service requirements because overly stringent criteria add directly to the cost. For critical service both surface and internal examination may be required to assure the attainment of the level of soundness specified. Visual Examination Equipment Required

Enables Detection of

Advantages

Limitations

Remarks

Surface comparator

Surface flaws – cracks, porosity, slag inclusions, adhering sand, scale, etc.

Low cost

Applicable to surface defects only

Should always be the primary method of inspection, no matter what other techniques are required

Pocket rule Straight Edge

Can be applied while work is in process, permitting correction of faults

Provides no permanent record

Workmanship standards

ASTM A 802/A 802M – 95

Standard Practice for Steel Castings, Surface Acceptance Standards, Visual Examination

SCRATA Comparators

Steel Casting Research and Trade Association (SCRATA) Comparator Plates for establishing mutually agreeable acceptance criteria for a specific part

ISO DIS 1197(a)

Visual examination of surface quality of steel castings

MSS SP-55-1996

Quality Standard for Steel Castings for Valves, Flanges and Fittings, and Other Piping Components (Visual Method for Evaluation of Surface Irregularities)

Liquid Penetrant Examination (PT) Equipment Required


Advantages

Limitations

Commercial kits, containing fluorescent or dye penetrants and developers

Surface discontinuities not readily visible to the unaided eye

Applicable to magnetic, nonmagnetic materials

Only surface discontinuities are detectable

Application equipment for the developer

Remarks

Easy to use Low cost

A source of ultraviolet light – if fluorescent method is used

ASTM A 903/A 903M – 91

Steel Castings, Surface Acceptance Standards, Magnetic Particle and Liquid Penetrant Inspection

ASTM E 165 – 95

Standard Test Method for Liquid Penetrant Examination

ASTM E 433 – 71

Standard Reference Photographs for Liquid Penetrant Examination

ISO 3452

Non-destructive testing – Penetrant inspection – General principles 58

ISO 4987

Steel castings – Penetrant inspection

MSS SP-93-1987(92)

Quality Standard for Steel Castings and Forgings for Valves, Flanges and Fittings, and Other Piping Components (Liquid Penetrant Examination Method)

Magnetic Particle Examination (MT) Equipment Required


Advantages

Limitations

Remarks

Special commercial equipment

Excellent for detecting surface and subsurface discontinuities to approximately ¼” below the surface – especially cracks

Permits controlled sensitivity

Applicable to ferromagnetic materials only

Elongated discontinuities parallel to the magnetic field may not give pattern; for this reason the filed should be applied from two directions at or near right angles to each other

Magnetic powders – dry or wet form; may be fluorescent for viewing under ultraviolet light

Relatively low cost method

Requires skill in interpretation of indications and recognition of irrelevant patterns Difficult to use on rough surfaces

ASTM A 903/A 903M – 91

Steel Castings, Surface Acceptance Standards, Magnetic Particle and Liquid Penetrant Inspection

ASTM E 709 – 95

Standard Guide for Magnetic Particle Examination

ASTM E 125 – 63

Standard Reference Photographs for Magnetic Particle Indications on Ferrous Castings

ASTM E 1444 – 94a

Standard Practice for Magnetic Particle Examination

ISO 4986

Steel castings – Magnetic particle inspection

MSS SP-53-1995

Quality Standard for Steel Castings and Forgings for Valves, Flanges and Fittings, and Other Piping Components (Magnetic Particle Examination Method)

All the surface examinations require severity levels to be set for acceptance. Methods of establishing severity levels by assigning numerical values to discontinuity attributes are illustrated in Figure 1 for the length of single linear discontinuities and arrays of aligned linear or nonlinear discontinuities. For nonlinear indications, acceptance criteria are typically expressed by limiting the “major” dimension of the indication, the length and width, or the area of the indication. Note, Figure 1 is an example and is not part of any acceptance standard unless agreed upon by the producer and buyer of steel castings.

59

Figure 1: Length measurement of linear discontinuities; linear arrays of linear and non-linear discontinuities

Figure 2: Area measurement; diameter or length, and width measurement of discontinuity arrays

Li, Wi, Di = Length, width, diameter of individual discontinuities, or clusters L, W, D = Length, width, diameter of discontinuity arrays d = Distance between discontinuities, or discontinuity clusters Linear discontinuity = Li ≥ 3Wi Linear array = L ≥ 5W Distance between discontinuities within an array = d < Limax, that is, d < Dimax Limax, Dimax = Largest length, or diameter of discontinuity, or cluster within an array

The ASME Code has methods and acceptance criteria in Section III and Section VIII. In Section VIII (nonnuclear) para. 9-103(a) and 9-230(a) no linear discontinuities are allowed. This is a classic example of overly strict requirements because it requires all discontinuities to be eliminated. In Section III (nuclear) para. NB-2545.3 and NB-2546.3 allow indications of 1/16”. The nuclear section is actually easier to comply with because it does allow for some small indications without rework. The code contains high standards of quality, but these need not be used for all castings for all applications. Rather, the service conditions should be used to help choose appropriate levels of acceptance. 60

Radiographic Examination (RT) Equipment Required


Advantages

Limitations

Remarks

Commercial x-ray or gamma units, made especially for inspecting welds, castings, and forgings

Internal macroscopic flaws – cracks, porosity, blow holes, nonmetallic inclusions, shrinkage, etc.

When the indications are recorded on film, gives a permanent record

Requires skill in choosing angles of exposure, operating equipment, and interpreting indications

Radiographic inspection is required by many codes and specifications

Film and processing facilities

Requires safety precautions Cracks difficult to detect

Useful in qualification of processes Because of cost, its use should be limited to those areas where other methods will not provide the assurance required

ASTM E 94 – 93

Standard Guide for Radiographic Testing

ASTM E 142 – 92

Standard Method for Controlling Quality of Radiographic Testing

ASTM E 446 – 93

Standard Reference Radiographs for Steel Castings up to 2 in. in Thickness (3 Sets; X-rays, Iridium, Cobalt)

ASTM E 186 – 93

Standard Reference Radiographs for Heavy-walled (2 to 4-1/2 in.) Steel Castings (3 Sets; X-ray, Gamma Rays, Betatron)

ASTM E 280 – 93

Standard Reference Radiographs for Heavy-walled (4-1/2 to 12 in.) Steel Castings (2 Sets; X-ray, Betatron)

ASTM E192 – 95

Standard Radiographs of Investment Steel Castings for Aerospace Applications

ISO 4993

Steel castings – Radiographic inspection

ISO 5579

Non-destructive testing – Radiographic examination of metallic materials by Xand gamma rays – Basic rules

MSS SP-54-1995

Quality Standard for Steel Castings for Valves, Flanges and Fittings, and Other Piping Components (Radiographic Examination Method)

Ultrasonic Testing (UT) Equipment Required


Advantages

Limitations

Special commercial equipment, either of the pulse-echo or transmission type

Sub-surface discontinuities, including those too small to be detected by other methods

Very sensitive

Requires high degree of skill in interpreting pulse-echo patterns

Permits probing of joints inaccessible to radiography

Remarks

Permanent record is not readily obtained

Especially for detecting subsurface, planar discontinuities

ASTM A 609/A 609M - 91

Standard Practice for Castings, Carbon, Low-alloy, and Martensitic Stainless Steel, Ultrasonic Examination Thereof

ISO DIS 4992(a)

Steel castings – Ultrasonic inspection

MSS SP-94-1992

Quality Standard for Ferritic and Martensitic Steel Castings for Valves, Flanges and Fittings, and Other Piping Components (Ultrasonic Examination Method)

61

SPECIAL STANDARD PRACTICES

Ferrite Content ASTM A 800/A 800M

STEEL CASTINGS, AUSTENITIC ALLOY, ESTIMATING FERRITE CONTENT THEREOF This practice covers procedures and definitions for estimating ferrite content in certain grades of austenitic iron-chromium-nickel alloy castings that have compositions balanced to create the formation of ferrite as a second phase in amounts controlled to be within specified limits. Methods are described for estimating ferrite content by chemicals, magnetic, and metallographic means. The tensile and impact properties, the weldability, and the corrosion resistance of iron-chromium-nickel alloy castings may be influenced beneficially or detrimentally by the ratio of the amount of ferrite to the amount of austenite in the microstructure. The ferrite content may be limited by purchase order requirements or by the design construction codes governing the equipment in which the castings will be used. The quantity of ferrite in the structure is fundamentally a function of the chemical composition of the alloy and its thermal history. Because of segregation, the chemical composition, and, therefore, the ferrite content, may differ from point to point on a casting. Determination of the ferrite content by any of the procedures described in the following practice ASTM A 800/A 800M is subject to varying degrees of imprecision which must be recognized in setting realistic limits on the range of ferritic content specified. Sources of error include the following: 1. In Determinations from Chemical Composition – Deviations from the actual quantity of each element present because of chemical analysis variance, although possibly minor in each case, can result in substantial differences in the ratio of total ferrite-promoting to total austenite-promoting elements. Therefore, the precision of the ferrite content estimated from chemical composition depends on the accuracy of the chemical analysis procedure. 2. In Determinations from Magnetic Response – Phases other than ferrite and austenite may be formed at certain temperatures and persist at room temperature. These may so alter the magnetic response of the alloy that the indicated ferrite content is quite different from that of the same chemical composition that has undergone different thermal treatment. Also, because the magnets or probes of the various measuring instruments are small, different degrees of surface roughness or surface curvature will vary the magnetic linkage with the material being measured. 3. In Determinations from Metallographic Examinations – Metallographic point count estimates of ferrite percentage may vary with the etching technique used for identification of the ferrite phase and with the number of grid points chosen for the examination, as explained in Test Method E 562.

ISO WD 13520(c)

ESTIMATION OF FERRITE CONTENT IN AUSTENITIC STAINLESS STEEL CASTINGS

See original specification for details.

62

Welding ASTM A 488/A 488M

STEEL CASTINGS, WELDING, QUALIFICATIONS OF PROCEDURES AND PERSONNEL This practice established the qualifications of procedures, welders, and operators for the fabrication and repair of steel castings by electric arc welding.

ISO WD 11970(c)

WELD QUALIFICATION PROCEDURES FOR STEEL CASTINGS

63

CODE AND SPECIFICATION AGENCIES

American Society for Testing and Materials (ASTM) 100 Barr Harbor Drive West Conshohocken, PA 19428 (610) 832-9500 [www.astm.org]

American Bureau of Shipping (ABS) 2 World Trade Center, floor 106 New York, NY 10048 (212) 839-5000 [www.eagle.org]

American National Standards Institute (ANSI) - US International Standards Organization (ISO) member nd th 11 W 42 Street, 13 floor New York, NY 10036 (212) 642-4900 [www.ansi.org]

Lloyd’s Register of Shipping (LR) 20325 Center Ridge Road, Suite 670 Cleveland, OH 44116 (440) 331-3626 [www.lr.org]

American Society of Mechanical Engineers (ASME) - Boiler and Pressure Vessel Code Committee PO Box 2900 Fairfield, NJ 07007 (800) 843-2763 [www.asme.org]

National Association of Corrosion Engineers (NACE) 1440 South Creek Drive Houston, TX 77084 (281) 228-6200 [www.nace.org]

American Petroleum Institute (API) th 275 7 Avenue, floor 9 New York, NY 10001 (212) 366-4040 [www.api.org]

Association of American Railroads (AAR) 50 F Street NW, floor 3 Washington, D.C. 20001 (202) 639-2100 [www.aar.org]

Manufacturers Standardization Society of the Valve and Fitting Industry, Inc. (MSS) 127 Park Street NE Vienna, VA 22180-4602 (703) 281-6613 [www.mss-hq.com]

Defense Automated Printing Service (DAPS) - part of Department of Defense Single Stock Point (DODSSP) for Mil Specs & Standards DODSSP Building 4/Section D 700 Robbins Avenue Philadelphia, PA 19111-5098 (215) 697-2179 [www.dodssp.daps.mil]

Society of Automotive Engineers (SAE) 400 Commonwealth Drive Warrendale, PA 15096-0001 (724) 776-4841 [www.sae.org]

64

STEEL FOUNDERS’ SOCIETY OF AMERICA 780 McArdle Dr. Unit G, Crystal Lake, IL 60014, USA www.sfsa.org

SFSA Supplement 3 DIMENSIONAL CAPABILITIES OF STEEL CASTINGS 1. Introduction Dimensional tolerances are selected by the designer or purchaser to make sure that the part can perform its function reliably and fit into its designed location. Assigning dimensions to a part requires identifying the desired feature size. Tolerances communicate how much variation from the desired size can be tolerated. Overly stringent tolerances are costly and do not add value. They require added work to meet tolerances that may be beyond the process capability. Inadequate tolerances are a problem because parts may be able to meet the tolerance but fail to either fit or function in accordance with the design. To assign dimensions and tolerances to a part that is produced as a casting involves consideration of function and fit of the finished part, allowances for machining operations involved in producing the finished part, and production requirements such as draft and taper. Allowances for castings and the major tolerance considerations in the production of parts as steel castings are presented below. Along with this information a set of tolerance grades is introduced to facilitate communication on tolerances.

2. Allowances The shapes of cast steel components reflect not only the functional requirements of the component, but also manufacturability requirements dictated by the casting process. Castings shapes must incorporate the proper use of draft allowances for successful mold making and machining allowances for surfaces requiring more precision and better surface finishes than can be achieved in the as-cast conditions. Draft and machine finish allowance guidelines and practices are presented to assist in the specification of draft and machining allowances for castings. Similarly, size or pattern allowances must be incorporated into the production of patterns and coreboxes from which steel castings are made. These pattern allowances (sometimes call shrink rules) must also be correctly applied to ensure that final castings can meet customer dimensional tolerance requirements without extra pattern dimension adjustment cycles. Other castability guidelines that influence the recommended geometry of steel castings are discussed in “Steel 1 Casting Design”.

2.1 Draft (Taper) Allowances Draft should be designated on the casting drawing in consultation with the casting producer— typically in a drawing note. The draft angle selected should be no less than can be tolerated in the design. Figure 2.1 illustrates the use of draft on a typical pattern and corebox.

1

Figure 2.1 - Schematic illustration of a full split pattern and core box to produce a wheeltype casting. Note that draft is required on the vertical surfaces to allow the pattern to be drawn away from the mold. The core that will be made in the core box will form a cylindrical cavity to reduce machining.

2.1.1 Draft (Taper) Allowance Recommendations Table 2.1 presents general draft recommendations for steel castings. To ensure moldability, it is helpful to meet or exceed these draft allowances indicated on all surfaces perpendicular to the mold parting line. Table 2.1: Typical Draft (Taper) Allowances Molding Process Green Sand - Manual Green Sand - Automated No-bake & shell molding

Typical Draft (Taper) Angles Most Features Deep Pockets 1.5 ° 2.0 ° 1.0 ° 1.5 ° 1.0 ° 1.5 °

2.1.2 Factors Affecting Recommended Draft Allowances Machine molding will require a minimum amount of draft. Interior surfaces in green sand molds usually require more draft than exterior surfaces. Draft can be eliminated in some cases through special molding techniques, such as investment casting or through the use of cores. These situations and the specific amount of draft required should be discussed with personnel of the foundry that will produce the casting.

2

A specific dimensional tolerance on a drafted surface is generally referenced from the drafted surface rather than from the surface dimension before draft is applied. That is, draft is added to casting surfaces first before dimensional tolerances or geometric tolerances applied, Figure 2.2. Draft allowances can be incorporated into dimensional tolerances or geometric tolerances only upon consultation with the foundry. The dimensional changes needed to incorporate draft can be expressed as follows: DA = L tan Where: DA = Draft allowance L = Length = Draft angle

3

Figure 2.3 Dimensional tolerance zones on drafted (tapered) features (CT is the casting dimensional tolerance as defined in ISO- 8062)

2.2 Required Machining Allowance Guideline Castings that are to be machined must have sufficient metal stock on all surfaces requiring machining. The necessary allowance, commonly called the required machining allowance (RMA), machine finish allowance, or machining allowance, depends upon the size and shape of the casting, the surface to be machined, the hardness of the steel, roughness of the casting surface, and the tendency to distort. The required machining allowance is superimposed upon draft and pattern allowances. Required machining allowances are typically called out in drawings with a general note.

4

2.2.1 Required Machining Allowance

Table 2.2 - Required machining allowances (RMA) in millimeters for steel castings based on ISO 8062. Largest dimension mm over

Required machining allowance mm Note: A minimum of 6 mm RMA required on all cope casting surfaces Required machining allowance grade

up to and including 40

E

F

G

H

J

K

40 63 100 160 250 400

63 100 160 250 400 630

0.4 0.4 0.7 1.1 1.4 1.8 2.2

630

1000

2.5

3.5

5

7

10

14

1000

1600

2.8

4

5.5

8

11

16

1600

2500

3.2

4.5

6

9

13

18

2500

4000

3.5

5

7

10

14

20

4000

6300

4

5.5

8

11

16

22

6300

10000

4.5

6

9

12

17

24

-

0.5 0.5 1 1.5 2 2.5 3

0.5 0.7 1.4 2.2 2.8 3.5 4

0.7 1 2 3 4 5 6

1 1.4 2.8 4 5.5 7 9

1.4 2 4 6 8 10 12

Sand casting, hand molded use grade G – K Sand casting, machine molded (and shell) use grade F – H Investment casting use grade E

5

Table 2.2 - Required Machining allowance (RMA) in inches for steel castings based on ISO 8062. Largest dimension in. over

up to and including

Required machining allowance mm Note: A minimum of 0.25 in. RMA Required machining allowance grade E

F

H

J

1.6

1.6 2.5

0.016 0.016

0.020 0.020

0.020 0.028

0.028 0.040

0.040 0.055

0.055 0.080

2.5 6 10 16 25

4 10 16 25 40

0.028 0.055 0.070 0.087 0.100

0.040 0.080 0.100 0.120 0.140

0.055 0.110 0.140 0.160 0.200

0.080 0.160 0.200 0.240 0.280

0.110 0.220 0.280 0.360 0.400

0.160 0.320 0.400 0.480 0.560

40

60

0.110

0.160

0.220

0.310

0.430

0.630

60

100

0.130

0.180

0.240

0.350

0.510

0.710

100

160

0.140

0.200

0.280

0.390

0.550

0.790

160

250

0.160

0.220

0.310

0.430

0.630

0.870

250

400

0.180

0.240

0.350

0.470

0.670

0.940

-

G

K

2.2.2 Factors Affecting Required Machining Allowances The allowances expressed in Table 2.2 are conservative and should apply to short production run castings. They may be reduced for high production run castings when adequate preliminary consultation and machining trials have been carried out. Machine allowances for castings of very large size, such as greater than 15 ft (5000mm), should be determined through consultation with the foundry. The required machining allowance, when considered along with the casting feature dimensional tolerance, should be interpreted as shown in Figure 2.4.

6

A – Machining on one side of feature

B – External machining of boss

7

C – Internal machining

D – Machining of step dimension

Figure 2.4 Interpretation of required machining allowances along with casting feature tolerances. The dimensional allowance to be added to the casting section for machining purposes will depend on the design of the casting. Certain faces of a casting may require larger allowances than others as a result of their position in the mold. In particular, the cope surfaces of a large casting will require larger machining allowances than the drag surfaces or side walls. For cope surfaces in particular required machining allowances for cope surfaces of less than 0.25 inches (6mm) are generally not recommended. For this reason, it is recommended that critical machined surfaces be molded in the drag whenever possible. Sufficient excess metal should be allowed to satisfactorily accomplish the necessary machining operations. One very good rule is to allow enough “machining stock” so that the first cut remains below the cast surface on the metal by at least 1/16 in. (1.5 mm). Required machining allowances must be chosen with care. Critical surfaces that are fixtured using as-cast locators are sometimes preferred to avoid excess machine stock on critical surfaces.

8

3. Dimensional Tolerances Tolerances for dimensions of as-cast features are a matter for agreement between the producer and purchaser (We do not know who the consumer is) of the castings. However, to minimize the rejection of castings for dimensional reasons, the tolerances selected should be compatible with the capability of the process selected. Tolerances affect the cost and delivery of the castings. Most castings have only a few critical dimensions which require tight tolerances. Placing tight tolerances on dimensions which are not critical merely increases the final casting cost without benefit to the purchaser. However, where tolerances tighter than the process can normally produce are required, dimensional upgrading using one of the operations discussed later may be the least expensive method of satisfying the requirements. The best way to make this determination is through a joint effort in a value engineering or value analysis project. Good communications of requirements on the one hand and the processes needed to meet them on the other is the key. The International Organization for Standardization (ISO) has issued, ISO 8062, Castings – System of Dimensional Tolerances. This standard provides a system of tolerances and machining allowances for all castings, including steel castings. It assigns different dimensional tolerance grades based on the metal cast, the molding process used, the length of the casting feature, and the production quantity. The ISO 8062-1994 tolerancing scheme is the basis from which improved dimensional tolerances for steel castings have been developed by the SFSA. These SFSA 2000 steel casting dimensional tolerances should be used instead of the specific steel casting tolerance recommendation contained within ISO-8062-1994 for steel castings. These new dimensional tolerance also supersede the 1997 (SFSA developed) “T grades” dimensional tolerances. The production quantities, the casting design and the dimension type play an important role in determining the tolerances which can be met with the process because the complex contraction behavior of steel during solidification and cooling must be adequately compensated for in the construction of the pattern. The production of castings in large numbers usually provides the opportunities to make dimensional adjustments in pattern equipment or to compensate for unpredictable casting contraction behavior with one or more reverse engineering steps. These costly reverse engineering steps to adjust pattern dimensions are a function of the dimensional tolerance requirements established by the customer as well as the foundry’s process variability. The SFSA-2000 dimensional tolerances presented here are based on a statistical analysis of more than 140,000 casting features on production steel castings weighing from 6.5 to 12,000 lbs. for common steel molding processes. The dimensional capabilities from which these tolerances have been developed account for both the expected casting process variability and dimension centering errors that can be expected for typical short production series and long production series casting production, Tables 3.1-3.4.

9

3.1 SFSA 2000 Dimensional Tolerances for Steel Castings Table 3.1 Casting dimensional tolerance grades from ISO 8062-1994. These grade designations also used for SFSA 2000 steel casting tolerances

Raw Casting basic dimensions, mm

Total casting tolerance mm

Over

Casting tolerance grade CT

Up to & including

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

10

0.09

0.13

0.18

0.26

0.36

0.52

0.74

1

2

2

2.8

4.2

-

-

-

-

10

16

0.10

0.14

0.20

0.28

0.38

0.54

0.78

1.1

1.6

2.2

3

4.4

-

-

-

16

25

0.11

0.15

0.22

0.3

0.42

0.58

0.82

1.2

1.7

2.4

3.2

4.6

6

8

10

12

25

40

0.12

0.17

0.24

0.32

0.46

0.64

0.9

1.3

1.8

2.6

3.6

5

7

9

11

14

40

63

0.13

0.18

0.26

0.36

0.50

0.70

1

1.4

2

2.8

4

5.6

8

10

12

16

63

100

0.14

0.20

0.28

0.40

0.56

0.78

1.1

1.6

2.2

3.2

4.4

6

9

11

14

18

100

160

0.15

0.22

0.30

0.44

0.62

0.88

1.2

1.8

2.5

3.6

5

7

10

12

16

20

160

250

-

0.24

0.34

0.50

0.70

1

1.4

2

2.8

4

5.6

8

11

14

18

22

250

400

-

-

0.40

0.56

0.78

1.1

1.6

2.2

3.2

4.4

6.2

9

12

16

20

25

400

630

-

-

-

0.64

0.90

1.2

1.8

2.6

3.6

5

7

10

14

18

22

28

1

1.4

2

2.8

4

6

8

11

16

20

25

32

1.6

2.2

3.2

4.6

7

9

13

18

23

29

37

2.6

3.8

5.4

8

10

15

21

26

33

42

4

6.2

9

12

17

24

30

38

49

7

10

14

20

28

35

44

56

11

16

23

32

40

50

64

-

630

1000

-

-

-

-

1000

1600

-

-

-

-

-

1600

2500

-

-

-

-

-

-

2500

4000

-

-

-

-

-

-

-

4000

6300

-

-

-

-

-

-

-

-

6300

10000

-

-

-

-

-

-

-

-

-

-

10

Table 3.2 Casting dimensional tolerances adapted from ISO 8062-1994, (inches), also used for SFSA 2000 steel casting tolerances Raw Casting basic dimensions, in.

Total casting tolerance in.

Over


Up to & including

2

1 -

3

4

5

6

7

8

9

10

11

12

13

14

15

16

0.4

0.01

0.01

0.01

0.01

0.01

0.02

0.03

0.04

0.06

0.08

0.11

0.17

-

-

-

-

0.4

0.6

0.01

0.01

0.01

0.01

0.02

0.02

0.03

0.04

0.06

0.09

0.12

0.17

-

-

-

-

0.6

1

0.01

0.01

0.01

0.01

0.02

0.02

0.03

0.05

0.07

0.09

0.13

0.18

0.24

0.32

0.39

0.47

1

1.6

0.01

0.01

0.01

0.01

0.02

0.03

0.04

0.05

0.07

0.1

0.14

0.2

0.28

0.35

0.43

0.55

1.6

2.5

0.01

0.01

0.01

0.01

0.02

0.03

0.04

0.06

0.08

0.11

0.16

0.22

0.32

0.39

0.47

0.63

2.5

4

0.01

0.01

0.01

0.02

0.02

0.03

0.04

0.06

0.09

0.13

0.17

0.24

0.35

0.43

0.55

0.7

4

6

0.01

0.01

0.01

0.02

0.02

0.04

0.05

0.07

0.1

0.14

0.2

0.27

0.39

0.47

0.63

0.79

6

10

-

0.01

0.01

0.02

0.03

0.04

0.06

0.08

0.11

0.16

0.22

0.32

0.43

0.55

0.7

0.87

10

16

-

-

0.02

0.02

0.03

0.04

0.06

0.09

0.13

0.17

0.24

0.35

0.47

0.63

0.79

0.98

16

25

-

-

-

0.03

0.04

0.05

0.07

0.1

0.14

0.2

0.28

0.39

0.55

0.7

0.87

1.1

25

40

-

-

-

-

0.04

0.06

0.08

0.11

0.16

0.24

0.32

0.43

0.63

0.79

0.98

1.26

40

60

-

-

-

-

-

0.06

0.09

0.13

0.18

0.28

0.35

0.57

0.7

0.91

1.14

1.46

0.1

60

100

-

-

-

-

-

-

0.15

0.21

0.32

0.39

0.59

0.83

1.02

1.3

1.65

100

160

-

-

-

-

-

-

-

0.17

0.24

0.35

0.47

0.67

0.95

1.18

1.5

1.93

160

250

-

-

-

-

-

-

-

-

0.28

0.39

0.55

0.79

1.1

1.38

1.73

2.21

250

400

-

-

-

-

-

-

-

-

-

0.43

0.63

0.91

1.26

1.58

1.97

2.52

Table 3.3 SFSA 2000 for steel casting tolerance long-production series. Conditions

Select Tolerance Grades

All sand molding process fully capable, most appropriate for large castings

CT 12-14

Appropriate for most casting types and sand molding processes

CT 10-12

Within process capabilities, but not appropriate for all casting types and sand molding processes

CT 8-10

Investment Casting

CT 5-7

11

Table 3.4 SFSA 2000 steel casting tolerances for short-production series steel castings Conditions

Select Tolerance Grades

All sand molding process fully capable, most appropriate for large castings

CT 13-15

Appropriate for most casting types and sand molding processes

CT 11-13

Within process capabilities, but not appropriate for all casting types and sand molding processes

CT 9-11

Additional comments on the use of the SFSA 2000 steel casting dimensional tolerances can be found in the Appendix.

3.2 Variables Affecting Dimensional Tolerances The aforementioned steel casting dimensional tolerance recommendations are general recommendations that can be readily used by casting customers. Comprehensive SFSA steel casting dimensional capability studies have developed more detailed information on the process and geometric factors influencing the repeatability of steel casting dimensions. Overall industry dimensional capabilities as well as the capabilities of individual foundries are fully described. This information can be used by foundries to benchmark their dimensional capabilities, and to better quantify the effects of key variables affecting dimensional capabilities. The dimensional capability data presented here includes measurement uncertainty multiplying factors applied to the dimensional variability data from which it is based. This accounts for small non-centering errors expected during tooling validation sampling. The short production series dimensional capability prediction equations include a larger multiplying factor that accounts for non-centering errors from less rigorous sampling for tooling validation. Casting dimensional tolerance capabilities are expressed in terms of 10%, 50%, and 90% capabilities as follows: 10% Capability = 10% of the feature capabilities were less than this limit. 50% Capability = Average capability. 90% Capability = 90% of the feature capabilities were less than this limit. Figures 3.6-3.8 show the 10%, 50%, and 90% dimensional capabilities of 15 steel foundries using various sand molding processes compared to ISO casting tolerance (CT) grades. The foundry-tofoundry differences in dimensional capabilities reflect the broad range of casting sizes and shapes produced and the different sand molding processes used, as well as differences in process control. These keys factors influencing dimensional capabilities are presented here as a guide to both the casting customer and the casting producer.

12

3.2.1 Production Quantity Issues The production of castings in large numbers usually provides the opportunities to make dimensional adjustments in pattern equipment or to compensate for unpredictable casting contraction behavior with one or more reverse engineering steps. These costly reverse engineering steps to achieve dimensions may only be appropriate for high production castings. It requires the detailed dimensional characterization of many “first article” castings prior to making accurate pattern adjustments. Figure 3.1 illustrates the influence of centering on overall dimensional capabilities. The thoroughness of the casting dimensional inspection required to make adequate pattern adjustments depends on the tolerances assigned to a feature as well as to the foundries process variability.

Figure 3.1 Schematic representation of total dimensional capability including sampling Uncertainty errors (e) The number of replicate castings that must be inspected to minimize the “centering error” component of dimensional capability depends on the ratio of the foundry’s process capability compared to the casting dimensional tolerances required. This has been termed the “process capability ratio” (PCR). PCR = Total process variability Total customer tolerance Table 3.5 indicates minimum desired lot sizes to be used for sample casting inspection based on the process capability ratio. The process capability ratio is the ratio of the foundries expected feature dimensional variability (6) compared to the casting feature total dimensional tolerance. If fewer sample castings than the desired number are used during pattern validation, a variability multiplying factor shown in Table 3.6 must be used to reflect additional sampling errors that are a part of the foundry’s dimensional capabilities.

13

Table 3.5 Statistically determined minimum number of sample castings to minimize numbers of sample castings sampling errors for various process capability ratios (for =0.05 and =0.05) Process Capability Ratio less than 0.1 0.1-0.2 0.2-0.3 0.3-0.4 0.4-0.5 0.5-0.6 > 0.6

Number of sample castings (N) 1 2 2 3 5 11 44

Table 3.6 Dimensional variability multiplying factors for determining dimensional capabilities from dimensional variability estimates

Actual number of castings sampled (n) 1 2 3 5 11 44

Minimum desired sample size (from Table A1) (N) 1 2 3 5 11 44 Dimensional Variability (6) Multiplying Factors 1 1.32 1.32 1.32 1.32 1.32 1 1 1.23 1.23 1.23 1.23 1 1 1 1.18 1.18 1.18 1 1 1 1 1.14 1.14 1 1 1 1 1 1.09 1 1 1 1 1 1

These multiplying factors can be used to more correctly access dimensional capabilities from the process variability estimates. As casting tolerances tighten, more sample castings must be inspected to minimize sampling errors. The information from Table 3.6 has been used to estimate the short production series multiplier of 1.32 and the long production series multiplier of 1.09 used as the basis for the SFSA 2000 steel casting dimensional capability’s guidelines presented here. 3.2.2 Dimensional Capability Models Major factors that influence the dimensional tolerance, which can be held, are casting geometry, the molding process, and production techniques. In general the dimensional capabilities of green sand process are similar to that of other sand molding processes for smaller castings below 50 lbs. Above 200 lbs. the no-bake process typically produces castings with tighter tolerances than green sand. The shell molding process can produce castings with the tightest tolerances of all sand molding techniques, but is limited in casting size. It is important that these statements are not taken simply at face value. It is possible for foundries to have developed great expertise and process control to produce castings to tighter tolerance standards than would be normally anticipated. When requiring tolerance requirements tighter than these indicated in the guidelines presented here, the purchaser should discuss these molding process selection issues with the foundries concerned. Table 3.7 and Table 3.8 present dimensional capability prediction models for the various molding processes. Dimensional capabilities are expressed at 10%, 50% (average) and 90% total tolerance capabilities. For example, 90% capabilities indicate that 90% of the features measured had less variability than the total tolerance capability limit. These models have been developed from comprehensive dimensional studies of steel castings in the heat treated condition (as received by the customer) without any dimensional upgrading. The variables included in the models are the most significant factors influencing the dimensional variability of steel casting features.

14

Table 3.7 Dimensional capability models for steel casting (inches) Short Production Series 90% Capability 1.3 0.4 6 = 0.2050+0.0020*L +0.0098*W 50% Capability 1.3 0.4 6 = 0.0842+0.0020*L +0.0098*W 10% Capability 1.3 0.4 6 = -0.0363+0.0020*L +0.0098*W

Long Production Series 90% Capability 1.3 0.4 6 = 0.1710+0.0017*L +0.0081*W 50% Capability 1.3 0.4 6 = 0.0701+0.0017*L +0.0081*W 10% Capability 1.3 0.4 6 = -0.0303+0.0017*L +0.0081*W

No-Bake (castings up to 2000 lbs.)

90% Capability 0.9 0.8 6=0.1410+0.010*L +0.0002*W +0.0483*PL 50% Capability 0.9 0.8 6=0.0616+0.0087*L +0.0003*W +0.0484*PL 10% Capability 0.9 0.8 6=-0.0181+0.0073L +0.0003*W +0.0485*PL

90% Capability 0.9 0.8 6 = 0.1180+0.0084*L +0.0002*W +0.0403*PL 50% Capability 0.9 0.8 6 = 0.0513+0.0073*L +0.0002*W +0.0403*PL 10% Capability 0.9 0.8 6 = -0.0151+0.0061*L +0.0002*W +0.0404*PL

Shell (castings less than 100 lbs.)

90% Capability 1.4 6 = 0.0805+0.0039*L +0.0195*PL 1.4 -0.0018*PL*L 50% Capability 1.4 6 = 0.0430+0.0038*L +0.0196*PL 1.4 -0.0018*PL*L 10% Capability 1.4 6 = 0.0054+0.0037*L +0.0198*PL 1.4 -0.0018*PL*L

90% Capability 1.4 1.4 6 =0.0671+0.0032*L +0.162*PL-0.0015*PL*L 50% Capability 1.4 1.4 6 = 0.0358+0.0032*L +0.164*PL-0.0015*PL*L 10% Capability 1.4 1.4 6 = 0.0045+0.0031*L +0.165*PL-0.0015*PL*L

Green sand (castings up to 500 lbs.)

6 = total tolerance capability, in. PL = 1 if feature across the parting line, otherwise 0 L = feature length, in. W = casting weight, lbs.

15

Table 3.8 Dimensional capability models for steel castings (mm) Short Production Series 90% Capability 1.3 0.4 6=5.200+0.0007*L +0.340*W 50% Capability 1.3 0.4 6 = 2.140+0.0007*L +0.340*W 10% Capability 1.3 0.4 6 = -0.922+0.0007*L +0.340*W

Long Production Series 90% Capability 1.3 0.4 6 = 4.330+0.0006*L +0.284*W 50% Capability 1.3 0.4 6 = 1.780+0.0006*L +0.284*W 10% Capability 1.3 0.4 6 = -0.768+0.0006*L +0.284*W

No-Bake (castings up to 900 kg)

90% Capability 0.9 0.8 6=3.590+0.014*L +0.010*W +1.230*P L 50% Capability 0.9 0.8 6=1.560+0.012*L +0.012*W +1.230*P L 10% Capability 0.9 0.8 6=0.460+0.010*L +0.014*W +1.230*P L

90% Capability 0.9 0.8 6 = 2.990+0.018*L +0.009*W +1.020*PL 50% Capability 0.9 0.8 6 = 1.300+0.010*L +0.010*W +1.020*PL 10% Capability 0.9 0.8 6 = -0.383+0.008*L +0.012*W +1.030*PL

Shell (castings less than 50 kg)

90% Capability 1.4 6=2.040+0.001*L +0.494*PL1.4 0.0005*PL*L 50% Capability 1.4 6=1.090+0.001*L +0.499*PL1.4 0.0005*PL*L 10% Capability 1.4 6=0.138+0.001*L +0.504*PL1.4 0.0005*PL*L

90% Capability 1.4 1.4 6 = 1.700+0.0009*L +0.412*PL-0.0004*PL*L 50% Capability 1.4 1.4 6 = 0.909+0.0009*L +0.416*PL-0.0004*PL*L 10% Capability 1.4 1.4 6 = 0.115+0.0008*L +0.420*PL-0.0004*PL*L

Green sand (castings less than 230 kg)

6 = total tolerance capability, mm PL = 1 if feature across the parting line, otherwise 0 L= feature length, mm W = casting weight, kg

These models, from which the steel casting dimensional tolerance guidelines have been based, give a more complete picture of the expected influence of key factor influencing dimensional 2 variability. The correlation coefficients (r ) for these predictive equations ranged from 0.4-0.7, indicating that foundry-to-foundry variations dimensional capabilities were also significant. The ISO 8062-based dimensional tolerance guidelines indicated the feature length alone influences the expected dimensional variability for a given molding process and production series. However, as these models indicate, casting weight and whether or not a casting feature crosses the mold parting line also influences feature dimensional variability. The use of these predictive equations for assigning tolerances for steel casting features better reflects the expected process capabilities for the steel casting industry than the simpler SFSA 2000 dimensional tolerance guidelines.

16

3.2.3 Molding Process The specific molding process used to produce a steel casting can be expected to affect the dimensional capabilities. For a given size and shape sand casting shell molding can be expected to be the most dimensionally capable molding process followed by no-bake molding and green sand molding. However, the differences in dimensional capabilities for the various molding processes are less than the within foundry and foundry-to-foundry variation in dimensional capabilities for a given molding process. Therefore, although a given steel foundry may need to use the more repeatable shell molding process to hold close dimensional tolerances, another foundry may be readily able to achieve these close dimensional tolerances using green sand molding. Figures 3.6-3.8 illustrate the dimensional capabilities of steel foundries for the individual molding processes. They are expressed as 10%, 50%, and 90% capability conformance to ISO 8062 tolerance grades for both short and long production series castings.

a) Short production series

b) Long production series

Figure 3.6 Dimensional capabilities of green sand casting producers



Figure 3.7 Dimensional capabilities of no-bake casting producers

17



Figure 3.8 Dimensional capabilities of shell casting producer 3.2.3 Casting Geometry Features Influencing Dimensional Variability 3.2.3.1 Casting Length and Weight It is more difficult to maintain close feature tolerances in larger castings than on small castings. Both the casting weight and the feature length influence the process capability relative to dimensional tolerances in a nonlinear fashion as shown in the predictive equations shown previously in Table 3.7 and 3.8. As a general guideline, the expected influence of feature length and casting weight on dimensional variability can be more simply estimated,Table 3.9. Table 3.9 Estimate of the effect of feature length and casting weight on dimensional variability Factor

Dimensional Variability and Influence (in.) (mm.)

Feature length

0.006 in. additional 6 variability per inch of feature length

0.06 mm. additional 6 per mm of feature length

Casting Weight

0.00004 in. additional 6 variability per lb. of casting weight

0.002 mm. additional 6 variability per kg of casting weight

3.2.3.2 Mold Parting Line Many casting features cross the mold parting line. The expected dimensional variability of these features perpendicular to the parting line includes a component of parting line variability. The expected magnitude of this parting line variability component depends on the molding process, Table 3.10.

18

Table 3.10 Magnitude of parting line variability Parting Line Dimensional Variability Component Green Sand Molding

No significant additional variability expected

No-bake Molding

0.040 in. (1 mm) additional 6 variability across the parting line

Shell Molding

0.008 in. (0.2 mm) additional 6 variability across the parting line

The additional variability for no-bake casting features that cross the parting line is particularly significant. This parting line variability can be expected to vary significantly from foundry to foundry depending on the molding and tooling systems in use. The parting line component of dimensional variability for no-bake castings must be considered when selecting feature orientation for close-tolerance features. 3.2.3.3 Dimension Type From a manufacturability standpoint various casting feature types can be described depending on whether they are controlled by the mold alone, by a core only, or by combinations of these, with and without the effect of the mold parting line, Figure 3.9. In particular, features created between the mold and a core are affected by core placement during mold closing and the relative tolerances of the core and it’s mating core print. These additional “degrees of freedom” created by multiple mold pieces create additional feature dimensional variables. Similarly, close tolerance casting features exhibiting less dimensional variability can be expected when these features are created from a single component of mold or core tooling.

H

D

G

C

MOLD

CASTING

B

A

MOLD

CASTING

MOLD

A mold to mold across casting B mold to mold across mold C mold to mold across mold and casting D mold to mold across casting/mold/casting

MOLD

CASTING

F

E

Core

CASTING

MOLD

E mold to core across casting F core to core across core G mold to core across casting and core H mold to mold across casting/core/casting

Figure 3.9 Schematics representation of different mold relationships for dimension types

19

3.2.4 Foundry Process Factors Influencing Dimensional Variability The ability of a foundry to control casting feature variability is impacted by their ability to control critical aspects of process variability. The role of individual foundry process factors on dimensional variability have been evaluated independent of casting geometry and molding process. Table 3.11 summarizes the influence of foundry process factors on dimensional variability. Major trends from this Table indicated factors that were statistically significant at confidence levels> 90%. Minor trends were also identified even though no strict statistical significance of these variables was established. Also listed are variables that appeared to have no effect on resultant casting dimensional variability independent of casting size, shape and molding process. Table 3.11 Foundry process factor correlations influencing dimensional variability

Factor

Increase 6 dimensional varaibility

Significant Correlations

Daily, instead of monthly, pin and flask alignment monitoring Very poor pattern condition instead of good pattern condition Use of separate cope and drag instead of match plate patterns Use of weighted instead of clamped molds

0.08 in. (2 mm)

0.04 in. (1 mm)

0.03 in. (0.8 mm)

0.02 in. (0.5 mm)

0.0004 in. (mm) additional 6 variability per in. (mm) of largest casting dimension 0.003 in. (mm) additional 6 variability per in. (mm) of cope or drag height 0.02 in. (0.5 mm) additional 6 variability per unit increase in green sand compactibility number 0.02 in. (0.5 mm) additional 6 variability for features impacted by hills

Lesser Correlations

Largest casting dimension

Cope or drag height

Green sand compactibility

Use of chills

Use of reclaimed sand for molding

0.01 in. (0.25 mm) additional 6 Variability for no-bake molding compared to new sand

No Correlation

Alloy being cast Pour weight Mold area Casting bounding box Projected area of the casting Use of facing sand Use of mold wash

20

3.3 DIMENSIONAL CAPABILITIES – INVESTMENT CASTING Most, if not all, investment castings are produced in long production series, where more thorough sample casting inspection and comprehensive tooling adjustments are performed prior to casting production. Therefore, only long production series capabilities are indicated in the SFSA 2000 guidelines for investment casting. The SFSA 2000 dimensional tolerance guidelines for steel castings include recommended tolerance guidelines for steel investment castings. These recommendations better reflect the dimensional capabilities of steel investment casting than the recommendations contained in ISO 8062, or in alternative dimensional tolerance guidelines promulgated by the Investment Casting Institute. The capability of investment casters to produce castings to the ISO 8062 casting tolerance grades is shown in Figure 3.10, expressed in terms of their 90%, 50% and 10% conformance. Considerable producer-to-producer variation is observed. This overall dimensional behavior is modeled in Table 3.12.

10

90%

90% 50%

90%

ISO CT GRADES

8 90% 90%

6 4

50%

50%

2

90%

50% 10%

10%

90% 50% 50%

50%

10%

10%

10%

10%

10%

0 A

B

C

D

E

F

Overall

Figure 3.10 Long production series dimensional capabilities of investment castings

Table 3.12a Long Production Series Dimensional Capability – Investment Castings (in.) 90% Capability 50% Capability 10% Capability

6 = 0.285 + 0.005L + 0.0002W - 0.005PL 6 = 0.083 + 0.0005L + 0.0002W - 0.005PL 6 = 0.0011 + 0.005L + 0.002W - 0.005PL

Where 6 = total tolerance, in. PL = 1 if feature across the parting line, otherwise 0 L = feature length, in. W = casting weight, lbs.

21

Table 3.12b Long Production Series Dimensional Capabilities – Investment Castings (mm) 90% Capability 50% Capability 10% Capability

6 = 0.724 + 0.005L + 0.012W – 0.013PL 6 = 0.212 + 0.005L + 0.012W – 0.013PL 6 = 0.029 + 0.005L + 0.012W – 0.013PL

Where 6 = total tolerance, mm PL = 1 if feature across the parting line L = feature length, mm W = casting weight, kg

3.4 GAGING AND DIMENSIONAL UPGRADING The appropriate dimensional tolerances of as-cast surfaces are a matter for agreement between the producer and purchaser of the castings. However, to minimize the rejection of castings for dimensional reasons the tolerances selected should be comparable to the process capability for the particular set of operating conditions under consideration. Tolerances tighter than the process capability will necessitate that the casting be subject to special processing to upgrade the dimensional characteristics. Table 3.13 lists some of the additional operations or special manufacturing processes that may be performed to provide castings within tighter tolerance limits than can be expected from standard process capabilities. Table 3.13 – Additional operations employed to provide tighter tolerances

Pattern Upgrading Changes in Construction, mounting and/or material Alteration of patterns after production of sample castings (i.e. movement toward long production series tolerances) Molding and core making Changes in mold making equipment or molding process Upgrading of coreboxes or adjustments in core processes Finishing Gage grinding Straighten or press to gage Coining to gage Machine locating points Rough machine to gage Target machine casting Finish machine part

22

3.5 Weight Tolerances When weight considerations are important to the customer, and weight tolerances are necessary, a weight allowance is necessary to account for variations from average casting weight. Steel casting weight allowances, based on ISO 4990-1986 are summarized in Table 3.14. Table 3.14 Casting Weight (Mass) Tolerances 1

Machine Molded Castings Hand Molded Castings

±5% of average casting mass 2 ±7% of average casting mass

All other castings

< + 15% of calculated casting mass

2

1

Average casting weight based on the average weight of the first five true dimension castings manufactured. 2 Calculated casting weight based on the casting drawing which includes all casting allowances such as machining allowances. 4 Geometric Tolerances Geometric tolerances are tolerances that apply to the shape features of a casting. This category of tolerances is used to control form, profile orientation and location. To completely describe the shape of a component and assign tolerances on all aspects of its shape, geometric tolerances are needed for such features as parallelism, concentricity, flatness, etc. Tables 4.1-4.4 show the geometric tolerances that can be expected for steel castings, these values are based on work involved in the development of ISO 8062-2. The reader is referred to the specification for further details regarding the use of ISO 8062-2. The nominal lengths indicated in Table 4.1-4.4 shall be the largest dimension of the considered feature or features. Table 4.5, indicates which CTG from the previous tables should be used depending on the steel casting molding process used.

Table 4.1a - Tolerances on straightness, mm 1

Over

Total geometrical tolerance mm Casting geometrical tolerance grade (CTG) 4 5 6 7

Up to and including 10 0.18 0.27 0.4 0.6 10 30 0.27 0.4 0.6 0.9 30 100 0.4 0.6 0.9 1.4 100 300 0.6 0.9 1.4 2.0 300 1000 0.9 1.4 2.0 3.0 1000 3000 2.0 3.0 4.6 3000 10000 3.0 4.6 6.8 1) When a value is outside the table, individual tolerances shall be indicated.

23

Table 4.1b - Tolerances on straightness, in. 1

Over

Total geometrical tolerance in . Casting geometrical tolerance grade (CTG) 5 6 7 8

Up to and 4 including 0.4 0.007 0.011 0.016 0.024 0.035 0.4 1.2 0.011 0.016 0.024 0.035 0.055 1.2 4 0.016 0.024 0.035 0.055 0.079 4 12 0.024 0.035 0.055 0.079 0.118 12 40 0.035 0.055 0.079 0.118 0.181 40 120 0.079 0.118 0.181 0.268 120 400 0.118 0.181 0.268 0.343 1) When a value is outside the table, individual tolerances shall be indicated.

Table 4.2a - Tolerances on flatness, mm 1

Raw casting nominal length of the feature, mm Up to and Over including 10 10 30 30 100 100 300 300 1000 1000 3000 3000 10000 10000

Total geometrical tolerance mm *for reference Casting geometrical tolerance grade (CTG) 4 0.27 0.4 0.6 0.9 1.4

5 0.4 0.6 0.9 1.4 2.0 3.0 4.6

6 0.6 0.9 1.4 2.0 3.0 4.6 6.8

7 0.9 1.4 2.0 3.0 4.6 6.8 10

8 1.4 2.0 3.0 4.6 6.8 10 15

1) When a value is outside the table, individual tolerances shall be indicated.

Table 4.2b - Tolerances on flatness, in. Raw casting nominal length of the feature, in. Up to and including Over 0.4 0.4 1.2 1.2 4 4 12 12 40 40 120 120 400

1

Total geometrical tolerance, in . Casting geometrical tolerance grade (CTG) 4 0.011 0.016 0.024 0.035 0.055

5 0.016 0.024 0.035 0.055 0.079 0.118 0.181

6 0.024 0.035 0.055 0.079 0.118 0.181

7 0.035 0.055 0.079 0.118 0.181 0.268

8 0.055 0.079 0.118 0.181 0.268 0.394 0.591

1) When a value is outside the table, individual tolerances shall be indicated.

24

Table 4.3a - Tolerances on circularity, perpendicularity and symmetry. Raw casting; nominal length of the feature, mm

1

Total geometrical tolerance, mm

Casting geometrical tolerance grade (CTG) Up to and 4 5 6 7 8 including 10 0.4 0.6 0.9 1.4 2.0 10 30 0.6 0.9 1.4 2.0 3.0 30 100 0.9 1.4 2.0 3.0 4.6 100 300 1.4 2.0 3 4.6 6.8 300 1000 2.0 3.0 4.6 6.8 10 1000 3000 4.6 6.8 10 15 3000 10000 6.8 10 15 23 1) When a value is outside the table, individual tolerances shall be indicated. Over

Table 4.3b - Tolerances on circularity, perpendicularity and symmetry. Raw casting; nominal length of the feature, in.

1

Total geometrical tolerance,in.

Casting geometrical tolerance grade (CTG) Up to and 4 5 6 7 including 0.4 0.16 0.024 0.055 0.079 0.4 1.2 0.024 0.035 0.079 0.118 1.2 4 0.035 0.055 0.118 0.181 4 12 0.055 0.079 0.181 0.268 12 40 0.079 0.118 0.268 0.343 40 120 0.181 0.343 0.591 120 400 0.268 0.591 0.906 1) When a value is outside the table, individual tolerances shall be indicated. Over

Table 4.4a - Tolerances on coaxiality Raw casting; nominal length of the feature mm

1

Total geometrical tolerance mm

Casting geometrical tolerance grade (CTG) Up to and 4 5 6 7 8 including 10 0.6 0.9 1.4 2.0 3.0 10 30 0.9 1.4 2.0 3.0 4.6 30 100 0.4 2.0 3.0 4.6 6.8 100 300 2.0 3.0 4.6 6.8 10 300 1000 3.0 4.6 6.8 10 15 1000 3000 6.8 10 15 23 3000 10000 10 15 23 35 1) When a value is outside the table, individual tolerances shall be indicated. Over

25

Table 4.4b - Tolerances on coaxiality Raw casting; nominal length of the feature, in.

1

Total geometrical tolerance in .

Casting geometrical tolerance grade (CTG) Up to and 4 5 6 7 8 including 0.4 0.024 0.035 0.055 0.079 0.118 0.4 1.2 0.035 0.055 0.079 0.118 0.181 1.2 4 0.055 0.079 0.118 0.181 0.268 4 12 0.079 0.118 0.181 0.268 0.343 12 40 0.118 0.181 0.268 0.343 0.591 40 120 0.268 0.343 0.591 0.906 120 400 0.343 0.591 0.906 1.378 1) When a value is outside the table, individual tolerances shall be indicated. Over

Table 4.5 – Casting geometrical tolerances grades Method Sand cast, hand molding Sand cast machine molding and shell molding Investment casting

Steel 6 to 8 5 to 7 4 to 6

5. Patterns and Pattern Allowances Patterns are manufactured so that the castings produced from the pattern are typically at the nominal (aim) dimensions of the casting drawing. The pattern and its associated coreboxes must be produced with dimensions that compensate for feature-specific contraction and distortion that takes place during casting, solidification, heat treatment and subsequent processing. This is known as the pattern allowance (or shrink rule). If can be expressed as: Pattern Allowance (PA) = Pattern feature size – Casting feature size x 100% Casting feature size

Foundry-to-foundry differences during processing also must be taken into account when selecting the proper pattern allowance. Castings produced from the same pattern by different foundries, or by different sand molding methods such as green sand or no-bake sand will typically not be dimensionally identical. The type of molding method can be expected to influence the effective overall casting contraction of green sand castings. Harder green sand molds produced with high pressure molding machines may require different pattern allowances that are used for similar castings using manual jolt-squeeze molding methods. Pattern wear, as well as the shrinking and swelling of wood pattern materials due to humidity changes, can also be a source of casting dimensional variability. Dimensional variations will be greater from some pattern materials than for others. Table 5.1 contains a listing of common types of pattern materials for steel castings in order of decreasing pattern dependent dimensional variability.

26

Table 5.1 Degree of Variability in Dimensions for Different Pattern Materials Loose wood pattern Pine pattern, mounted on cope and drag boards Hard wood pattern, mounted on cope and drag boards Plastic pattern, mounted on cope and drag boards Metal pattern, mounted on cope and drag boards Metal matchplate

Greatest variation

Lowest Cost

Least variation

Highest Cost

Table 5.2 summarizes commonly used pattern allowances used for the production of steel castings. These overly simplified pattern allowances “shrink rules” are only a general “rule-ofthumb” that do not consider these important influences of feature type and mold type on the pattern allowance. Even though these standard, uniform pattern allowance “rules-of-thumb” are widely used, the shrinkage of individual casting features can be expected to deviate significantly from these pattern allowance nominal values. Table 5.2 General pattern allowance values for common steel casting alloys Alloy Carbon and low alloy steel High alloy steels

Pattern Allowance 2.08% 1/4 in/ft 2.60% 5/16 in/ft

The pattern allowance value must account for more than just the shrinkage of the metal during solidification and cooling. The mold itself can be expected to undergo dimensional changes during filling, solidification and cooling. Certain casting features are restrained from contraction during solidification by the presence of the mold, others are not. Also oxide scale removed from the casting surface after cooling and subsequent heat treatment result in casting dimensional changes. The heat produced during the cooling of large castings can cause the sand mold to expand before even solidification begins. All of these factors contribute to casting dimensional changes requiring the use of not a single pattern allowance by different feature-dependent pattern allowance values to assure the conformance of all casting feature dimensions to customer dimensional specifications. Table 5.3 gives more detailed information on pattern allowance selection for casting features not crossing the mold parting line. These pattern allowance estimates for high and low alloy steels are based on comprehensive studies of pattern allowances measured in production foundries for green sand, no-bake and shell molding.

27

Table 5.3 Pattern Allowance Summary (for features not crossing the mold parting line) Average Pattern Allowance

80% Confidence Interval for Pattern Allowances

1.96%

1.85 to 2.07%

Green sand molding, overall Un-restrained features Partially restrained features Fully restrained features

1.60% 1.56% 1.74% 1.61%

1.43 to 1.77% 1.15 to 1.97% 1.56 to 1.92% 1.48 to 1.74%

No bake molding, overall Un-restrained features Partially restrained features Fully restrained features

2.39% 2.33% 2.32% 2.03%

2.20 to 2.58% 1.94 to 2.74% 2.06 to 2.59% 1.75 to 2.30%

Shell molding, overall Un-restrained features Partially restrained features Fully restrained features

2.31% 2.87% 2.31% 1.27%

2.10 to 2.51% 2.58 to 3.16% 2.13 to 2.48% 0.91 to 1.63%

2.92%

2.72 to 3.11%

Green sand molding, overall Un-restrained features Partially restrained features Fully restrained features

4.21% 3.62% -5.37%

3.82 to 4.59% 3.34 to 3.83% -4.98 to 5.76%

No bake molding, overall Un-restrained features Partially restrained features* Fully restrained features*

3.50% 4.04% ---

3.08 to 3.92% 3.46 to 4.63% ---

Shell molding, overall Un-restrained features Partially restrained features Fully restrained features

2.58% 2.90% 2.42% 1.57%

2.35 to 2.81% 2.57 to 3.24% 2.29 to 2.54% 1.28 to 1.85%

Condition Low Alloy Steel Overall

High Alloy Steel Overall

28

6. Summary Table 6.1 summarizes the general dimensional and cost considerations for common steel casting methods. It reflects the general capabilities common to the steel foundries. Individual foundries may have even greater dimensional capabilities and lower cost and lead time performance.

Table 6.1 General Comparison of Steel Casting Methods*

Casting Green sand Chemically Shell Investment requirements bonded Surface Fair Good Good Excellent smoothness Minimum metal 6 (0.25) 5 (0.19) 4 (0.16) 2 (0.06) section-mm (in). 3.4 (0.13) 2.5 (0.10) 1.7 (0.07) 0.8 (0.03) Total (6) tolerance for a 100 mm (4in.) features – mm (in.) 3 (0.12) 4 (0.16) 2 (0.06) No parting Added total tolerance-mm (in.) across a parting face Intricacy Fair Good Very good Excellent Most 2 (0.06) Least General Machine 6 (0.25) 5 (0.19) 0.5 (0.02) Finish allowances **mm (in.) Normalized 100% 80% 250% 175% Pattern costs Lead time 18 weeks 12 weeks 20 weeks 22 weeks (pattern) Lead time 6 weeks 6 weeks 6 weeks 8 weeks (existing pattern) * Values are presented for comparison only and should not be used directly as design tolerances on drawings, or for pattern procurement. References (1) (2)

th

Steel Casting Handbook, 5 Edition, SFSA (1980). Karve, A., J. Chandra, and R. Voigt, "Determining Dimensional Capabilities from Short Run Sample Casting Inspection", AFS Transactions (1998).

29

Appendix: Guidelines for the use of SFSA 2000 Dimensional Tolerances General The tolerance guidelines are provided for information to be used by foundries and customers to address dimensional deviations. A customer can express the dimensional accuracy desired. A foundry can, with reference to the tolerance grade, give information on which tolerance grade or grades it normally attains with different molding methods and for different casting types. It is recommended that the customer ask the foundry about the dimensional accuracy obtained with different molding methods and resources at its disposal. With this knowledge, the designer can decide if closer tolerances are needed for selected dimensions. Scope This appendix describes the tolerances, which may be achieved on steel castings produced in sand molds and for steel investment castings. Steel sand castings may be produced by molding processes such as green sand, chemically bonded sands, shell and other processes. Purchasing information The customer should indicate on the drawing the dimensions which are to be subject to the tolerance tables and the tolerance grades to be achieved. The required machining allowance should also be indicated when a machined part drawing is used. Where the purchaser has supplied a drawing which indicates the machined surfaces and the machining allowance, but has not indicated the tolerance grade required for these surfaces, the foundry is free to supply the casting to their normal performance capability. Tolerance grades Typically, the lowest sand molding tolerance values may be expected in castings produced by the shell process. However, manufacturers may be able to achieve similar tolerances with other molding processes. The lower number tolerance grades are more applicable to shell and no-bake molding methods. Higher number tolerance grades are applicable for many green sand-molding processes where few pattern changes and/or process adjustments can be made. The tolerance grade specified should also reflect the extent of pattern dimensional re-engineering to center casting feature dimensions within the specified tolerances. The extent of inspection required to achieve the specified tolerance values is indicated by the selection of short production series or long production series tolerance values. Where tighter tolerances than those found in the tables are required, these shall be agreed between the purchaser and supplier.

Inspection The foundry will determine the compliance of the part with the purchasers’ requirements. The SFSA-2000 tolerance grades (Tables A1 to A4) are to be applied to heat treated and shot blasted production steel castings which have not been upgraded by gaging, grinding, coining, pressing or other dimensional upgrading procedures. They express the 90% conformance of foundries in terms of ISO-8062 dimensional tolerance grades.

30

Table A.1 Casting dimensional tolerance grades from ISO 8062-1994. These grade designations also used for SFSA 2000 steel casting tolerances

Raw Casting basic dimensions, mm

Total casting tolerance, mm

Over


Up to & including

1 -

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

10

0.09

0.13

0.18

0.26

0.36

0.52

0.74

1

2

2

2.8

4.2

-

-

-

-

10

16

0.10

0.14

0.20

0.28

0.38

0.54

0.78

1.1

1.6

2.2

3

4.4

-

-

-

-

16

25

0.11

0.15

0.22

0.3

0.42

0.58

0.82

1.2

1.7

2.4

3.2

4.6

6

25

40

0.12

0.17

0.24

0.32

0.46

0.64

0.9

1.3

1.8

2.6

3.6

5

40

63

0.13

0.18

0.26

0.36

0.50

0.70

1

1.4

2

2.8

4

5.6

63

100

0.14

0.20

0.28

0.40

0.56

0.78

1.1

1.6

2.2

3.2

4.4

100

160

0.15

0.22

0.30

0.44

0.62

0.88

1.2

1.8

2.5

3.6

160

250

-

0.24

0.34

0.50

0.70

1

1.4

2

2.8

4

250

400

-

-

0.40

0.56

0.78

1.1

1.6

2.2

3.2

4.4

400

630

-

-

-

0.64

0.90

1.2

1.8

2.6

3.6

630

1000

-

-

-

-

1

1.4

2

2.8

4

1000

1600

-

-

-

-

-

1.6

2.2

3.2

1600

2500

-

-

-

-

-

-

2.6

2500

4000

-

-

-

-

-

-

-

4000

6300

-

-

-

-

-

-

-

-

6300

10000

-

-

-

-

-

-

-

-

8

10

12

7

9

11

14

8

10

12

16

6

9

11

14

18

5

7

10

12

16

20

5.6

8

11

14

18

22

6.2

9

12

16

20

25

5

7

10

14

18

22

28

6

8

11

16

20

25

32

4.6

7

9

13

18

23

29

37

3.8

5.4

8

10

15

21

26

33

42

4

6.2

9

12

17

24

30

38

49

7

10

14

20

28

35

44

56

11

16

23

32

40

50

64

-

31

Table A.2

Casting dimensional tolerances adapted from ISO 8062-1994 (inches) also used for SFSA 2000 steel casting tolerances

Raw Casting basic dimensions, in.

Total casting tolerance, in.

Over


Up to & including

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

0.4

0.01

0.01

0.01

0.01

0.01

0.02

0.03

0.04

0.06

0.08

0.11

0.17

-

-

-

-

0.4

0.6

0.01

0.01

0.01

0.01

0.02

0.02

0.03

0.04

0.06

0.09

0.12

0.17

-

-

-

-

0.6

1

0.01

0.01

0.01

0.01

0.02

0.02

0.03

0.05

0.07

0.09

0.13

0.18

0.24

0.32

0.39

0.47

1

1.6

0.01

0.01

0.01

0.01

0.02

0.03

0.04

0.05

0.07

0.1

0.14

0.2

0.28

0.35

0.43

0.55

1.6

2.5

0.01

0.01

0.01

0.01

0.02

0.03

0.04

0.06

0.08

0.11

0.16

0.22

0.32

0.39

0.47

0.63

2.5

4

0.01

0.01

0.01

0.02

0.02

0.03

0.04

0.06

0.09

0.13

0.17

0.24

0.35

0.43

0.55

0.7

4

6

0.01

0.01

0.01

0.02

0.02

0.04

0.05

0.07

0.1

0.14

0.2

0.27

0.39

0.47

0.63

0.79

-

6

10

-

0.01

0.01

0.02

0.03

0.04

0.06

0.08

0.11

0.16

0.22

0.32

0.43

0.55

0.7

0.87

10

16

-

-

0.02

0.02

0.03

0.04

0.06

0.09

0.13

0.17

0.24

0.35

0.47

0.63

0.79

0.98

16

25

-

-

-

0.03

0.04

0.05

0.07

0.1

0.14

0.2

0.28

0.39

0.55

0.7

0.87

1.1

25

40

-

-

-

-

0.04

0.06

0.08

0.11

0.16

0.24

0.32

0.43

0.63

0.79

0.98

1.26

40

60

-

-

-

-

-

0.06

0.09

0.13

0.18

0.28

0.35

0.57

0.7

0.91

1.14

1.46

60

100

-

-

-

-

-

-

0.1

0.15

0.21

0.32

0.39

0.59

0.83

1.02

1.3

1.65

100

160

-

-

-

-

-

-

-

0.17

0.24

0.35

0.47

0.67

0.95

1.18

1.5

1.93

160

250

-

-

-

-

-

-

-

-

0.28

0.39

0.55

0.79

1.1

1.38

1.73

2.21

250

400

-

-

-

-

-

-

-

-

-

0.43

0.63

0.91

1.26

1.58

1.97

2.52

Table A.3 SFSA 2000 for steel casting tolerance long-production series. Conditions All sand molding process fully capable, most appropriate for large castings Appropriate for most casting types and sand molding processes Within process capabilities, but not appropriate for all casting types and sand molding processes Investment Casting

Select Tolerance Grades CT 12-14 CT 10-12 CT 8-10 CT 5-7

32

Table A.4 SFSA 2000 steel casting tolerances for short-production series steel castings Conditions All sand molding process fully capable, most appropriate for large castings Appropriate for most casting types and sand molding processes Within process capabilities, but not appropriate for all casting types and sand molding processes

Select Tolerance Grades CT 13-15 CT 11-13 CT 9-11

33

STEEL CASTINGS HANDBOOK Supplement 7 Welding of High Alloy Castings

Steel Founders' Society of America 2004

Welding of high alloy steel castings by E. A. Schoefer Consultant Steel Founders’ Society of America Edited by M. Blair Steel Founders’ Society of America 1. Introduction Iron-base and nickel-base high alloys - by definition those containing eight percent or more of another element - are widely used for construction of industrial process equipment that must resist the deteriorating effect of a corrosive of high temperature environment. Both wrought and cast forms of such alloys may be welded during the manufacture of finished components so the weldability of the alloys often is a matter of concern to the user. The same welding processes are applied to wrought and cast products and, in general, similar techniques and practices are employed. Differences between wrought and cast alloys in chemical composition and microstructure, however, influence the welding characteristics of each form and must be given consideration. In addition, the high alloys differ markedly from carbon and low alloy steels in physical properties such as electrical resistance, thermal expansion and thermal conductivity. It is essential, therefore, to employ procedures allowing for all these factors when welding high alloy castings. 1.1 All the casting alloys have equal or better weldability than the corresponding wrought alloys, but there are variations from grade to grade in the ease with which satisfactory welds are obtained. The low-carbon, austenitic grades usually are considered easier to weld than high-carbon austenitic or straight-chromium ferritic or martensitic types. Nevertheless, each of the standard alloy compositions can be welded successfully in the foundry. Using information derived from the extensive research of Alloy Casting Institute and Steel Founders’ Society of America, the foundryman often is able to tailor the composition balance especially to provide the optimum weldability. Accordingly, castings are readily welded into fabricated structures and welding is considered a regular part of the foundry production process. 1.2 Welding is used a procedure for upgrading casting quality during the course of manufacture through improvement of surface conditions, or by elimination of shrinkage voids. It is also used for producing large or complex assemblies where the size of the completed structure precludes production as a one-piece castings, or where total quality will be improved by dividing the structure into simpler components which can later be welded int an integral assembly. 1.3 Welds properly made do not impair high alloy castings with respect to their corrosion resistance or their mechanical properties from sub-zero to elevated temperatures.

1

Proven welding techniques that are procedurally correct and metallurgically sound involve consideration of the following factors: a. Characteristics of the alloy type b. Choice of filler material c. Preparation of the weld cavity or joint d. The weld process to be used e. Preweld and postweld heat treatment f. Methods of demonstrating weld quality All of these topics will be covered in subsequent sections of this discussion or in the accompanying welding procedure descriptions. 2. Properties of the alloy types At the outset it is necessary to review the microstructures and the physical and mechanical properties of the different high alloy types because the effects of exposure to welding temperatures vary among the alloy grades. The microstructures that are developed during welding influence the physical and mechanical properties of the alloys, and they, in turn, influence the soundness of the welds. Four classes of high alloy castings will be discussed: a) Iron-Chromium, b) Iron-Chromium-Nickel, c) IronNickel-Chromium, and d) Nickel-base. The cast alloys are also classified according to their end use as “corrosion resistant” or “heat resistant” and there are important differences in the alloy compositions used in each group. In the corrosion resistant category by far the greatest tonnage of castings is produced in the iron-chromium-nickel class, with iron-chromium types in second place; whereas in the heat resistant group the iron-nickel-chromium alloy types rank almost equally with the iron-chromium-nickel class. The heat resistant alloys are generally higher in alloy content than the corrosion resistant types and in nearly all cases are substantially higher in carbon content. These differences make it desirable to consider the corrosion and heat groups separately. 2.1 Corrosion resistant grades Electrical resistivity of the corrosion resistant alloys is five to ten times higher than carbon steel. Welding current requirements therefore, are lower than for carbon steel and attention should be given to the amperage and voltage recommendations of the filler metal manufacturer. Excessive heat input should be avoided because the low thermal conductivities of the high alloys (about 50 percent less than steel) combined with the generally higher thermal expansion coefficients (about 50 percent greater than steel) tend to create steep temperature gradients and high thermal stresses in the weld zone. 2.1.1 Iron-chromium alloy types are martensitic or ferritic in microstructure depending on the chromium and carbon content in the composition. They are sub-divided, therefore, into “hardenable” and “non-hardenable” groups. 2.1.1.1 The CA15 and CA40 (11.5 - 14 Cr) hardenable alloys transform to austenite in the weld and in the heat affected zone of the base metal. Transformation of the

austenite to hard, brittle martensite is essentially completed at about 300oF (149oC) on cooling from welding temperature and will promote weld cracking - the higher the carbon content the greater the cracking tendency. For this reason castings are preheated to about 500oF (260oC) and maintained above the martensite transformation temperature during welding. As soon as possible after welding, and without cooling below 300oF (149oC), castings are heated to 1100 - 1450oF (593 - 788oC) and cooled to temper any martensite that has formed and to restore the ductility and impact strength of the metal. Stray arc strikes can cause hard spots and should be avoided. These alloys have coefficients of thermal expansion similar to carbon steel but are sometimes welded using austenitic, iron-chromium-nickel filler metal which has a coefficient about 50 percent greater. In addition to the differences in ductility and hardness, the difference in expansion characteristics of the base and weld metals should be considered before using such filler metal, particularly if the welded structure will be subjected to heating and cooling in service. 2.1.1.2 The CB30 (18 - 22 Cr) and CC50 (26 - 30 Cr) non-hardenable alloys are subject to rapid grain growth during welding which reduces their ductility and promotes cracking. Furthermore, although the alloys are essentially ferritic, it is possible for some austenite to form and subsequently transform to martensite. Preheating to above 400oF (204oC) sometimes as high as 1300oF (704oC) usually is necessary, therefore to obtain satisfactory welds. Postweld heat treatment is required to reduce brittleness in the weld zone. The CB30 alloy customarily is heated to 1450oF (788oC) and the CC50 alloy to 1650oF (899oC) or higher then air cooled. Rapid cooling through the range 1100 - 750oF (593 - 399oC) is advisable to avoid embrittlement. If conditions of service permit the welded area to have mechanical properties different from the remainder of the casting, an austenitic filler metal can be used to improve the ductility of the weld deposit. This does not change the need for pre- and pot-weld heat treatments, however, because the dilution of the base metal with nickel increases the probability of martensite formation. Consideration also must be given to difficulties that might arise from the difference in thermal expansion coefficients of the weld and base metals. 2.1.2 Iron-chromium-nickel alloys with additions of copper (CB7Cu) or copper and molybdenum (CD4MCu) are high-strength, two-phase austenite-martensite or austeniteferrite structures. At elevated temperatures the CB7Cu grade is transformed to austenite most of which forms martensite on cooling below 300oF (149oC). This is a relatively soft martensite, however because of the low carbon content. Copper, retained in the martensite as a super-saturated solution, precipitates sub-microscopically if the alloy is reheated to the range 900-1100oF (482-593oC) and subsequently increases the strength and hardness of the casting. In either the annealed or hardened condition castings can be welded without preheat, although it sometimes desirable to preheat tp 500oF (260oC) when welding heavy sections. Sections which require multi-pass welds are handled better in the annealed condition than after aging since the prolonged heat of welding will introduce non-uniform hardening characteristics to the weld zone. Thus, such castings require a solution heat treatment in the temperature range 1850 -1950oF (1010 -

1066oC) followed by rapid cooling before being hardened by reheating to the precipitation temperature. Only the low temperature aging treatment is needed to harden the weld zone on single pass welds. The CD4MCu alloy has very low carbon content, but the two-phase, austenite-ferrite microstructure is strengthened by the copper and molybdenum contents. Properties of the alloy are influenced critically by the chemical composition balance so it is essential that the filler metal used in welding this grade create a weld deposit closely matching the base metal. Castings are welded in the solution annealed condition and preheat is not required. To restore the ductility and maximum corrosion resistance to the weld zone, castings require a postweld solution heat treatment at 2050oF (1121oC) or higher, slow cooling to 1900oF (1038oC) to allow transformation of some ferrite to austenite, followed by rapid cooling to room temperature. 2.1.3 Iron-chromium-nickel alloy types CE30, CF3, CF8, CF20, CF8C, CF3M, CF8M, CG8M, CH20 and CK20 are all austenitic in microstructure. Depending on the balance in the chemical composition among the austenite-promoting elements (nickel, carbon, manganese and nitrogen) and the ferrite-promoting elements (chromium, silicon, molybdenum, and columbium), the structure may vary from wholly austenite to austenite plus ferrite in the range 0 to 40 percent. In this respect the casting alloys differ from the corresponding wrought stainless steels which normally are balanced to be wholly austenitic since partially ferritic alloys have inferior rolling qualitites. The corrosion resistance of the alloys is greatest when the carbon is completely dissolved and this accomplished by heating them to 1900oF (1038oC) or higher, followed by rapid cooling through the range 1600 to 800oF 871 tp 427oC). If the alloys cool slowly through the “sensitizing” temperature range, there is a danger that the carbon will combine with some of the chromium and precipitate as chromium carbide. Since a high chromium content is essential to maximum corrosion resistance, any area that has been depleted of chromium by the precipitation of chromium carbide will be subject to increased corrosive attack. This is so-called “weld-decay” in which severe corrosion is experienced in the heat affected zone adjacent to a weld.

When wholly austenitic microstructures such as usually found in wrought alloys are exposed to sensitizing temperatures they suffer from intergranular corrosion because the chromium carbides precipitate along the grain boundaries and thus form a continuous network along which corrosion can proceed. Due to the presence of some ferrite in castings, on the other hand, the carbides precipitate in the discontinuous ferrite pools so that intergranular attack is less likely to occur. Nevertheless, to restore maximum corrosion resistance to the weld zone, the carbides must be redissolved by a high temperature heat treatment and a rapid quench. The extra-low carbon content of alloys CF3 and CF3M can be welded without postweld heat treatment because very little chromium carbide can be formed. Chromium depletion is avoided in the CF8C alloy type by the intentional addition of columbium carbides instead of chromium carbides.

The presence of ferrite in the microstructure of the austenitic alloys is also helpful in avoiding cracking or microfissuring of welds. Consequently, the CE30, CF3, CF8, CF16F, CF3M, CF8M, CF8C and CG8M grades, which normally contain over 5 percent ferrite, are less susceptible to cracking than the wholly austenitic types CH20 and CK20. Because as previously noted, wrought stainless steels of the AISI 300 series are generally balanced to have wholly austenitic structures, they are prone to cracking when welded so the filler compositions used are usually balanced to a partially ferritic weld deposit and thereby take advantage of the improved resistance to microfissuring provided by this structure. Since may of the casting alloys are themselves partially ferritic, these grades can be welded more readily than the wrought types without the use of filler metal, as in the case of the inert gas tungsten welding process often used for fusion of root passes or elimination of small surface discontinuities. Upper limits on the ferrite contents of castings and weld deposits are frequently set when heavy sections are to be welded or where the service temperature may exceed 800oF (427oC). High chromium alloys held for appreciable times at elevated temperatures may transform partially to the sigma phase with resultant decrease in high temperature strength and room temperature ductility. This transformation can take place after long exposure of alloys that are initially wholly austenitic, but may occur quite rapidly in partially ferritic alloys. Embrittlement and possible cracking of high ferrite content weld deposits may result form the slow cooling of heavy sections so that nominal ferrite contents are usually limited to maximum amounts depending on experience with specific casting configurations. Small amounts of sigma that may form in a ferrite-containing weld of a heavy section will be eliminated, however, through retransformation to ferrite by a postweld solution heat treatment. Although there are several methods for estimating the amount of ferrite present in an austenitic alloy, the one most often used is based on the fact that ferrite is ferromagnetic whereas austenite is not. Instruments for measuring the magnetic attraction of a weld deposit or casting have assumed to be capable of determining the true percentage of ferrite present. Recent investigations have shown, however, that no method is yet available for the accurate determination of absolute ferrite content. Accordingly, a method has bee approved by the Advisory Subcommittee of the Welding Research Council for calibrating magnetic measuring instruments to read in “Ferrite Numbers”. (See Item 20 in the Bibliography.) It should be recognized that considerable variation of indicated ferrite content will occur over the surface of a casting or weld zone, and due allowance should be made for this in any specification. For example, a spread of ferrite number from 4 to 16 should not be unexpected when the nominal value is 10. 2.1.4 The iron-nickel-chromium and nickel-base alloys CN7M, CW12M, CY40, N12M, M-35, and CZ100 are “austenitic” in microstructure and do not undergo change in phase when cooling from welding temperature. They are subject to carbide precipitation, however, and have lowered ductility in the 1200 to 1800oF (649 to 928oC) temperature range. Cracking of the weld zone may occur for this reason if there is substantial restraint, and in such cases preheat is sometimes helpful as indicted on the individual

alloy procedure sheets. Another cause of cracking in high alloys is embrittlement from contamination of the weld by lead, sulfur, phosphorous and other elements such as arsenic and antimony. Producers o castings exert great care to ensure low levels of these contaminants in the alloys, and similar care must be exercised in keeping weld areas and the heat affected zones clean. Anything that might contribute one or more of the detrimental elements-marking crayon, paint, oil and even some degreasing compounds can be such sources - should be removed by a final washing with alcohol, acetone of hot water before starting to weld. Removal of all traces of molding sand by grinding the surface in the weld area is desirable for type —35 and sometimes for other alloys. Castings are usually welded in the solution annealed condition and are given a postweld heat treatment to restore corrosion resistance and relieve stresses. 2.2 Heat resistant grades These have physical properties similar to the corrosion resistant grades so that some of the same considerations apply with regard to electrical characteristics and thermally imposed stresses. The generally higher carbon contents of the heat resistant alloys makes them stronger at elevated temperatures than the corrosion resistant types and the extensive carbide networks in the microstructures result in relatively low room temperature ductility. 2.2.1 Iron-chromium alloy type HA is a hardenable, pearlitic-martensitic alloy that has good oxidation resistance at temperatures up to about 1200oF (649oC). Its behavior in welding is similar to that described for the CA alloys in Section 2.1.1.1. Type HC has the same microstructure and welding characteristics as the CC50 alloy discussed in Section 2.1.1.2. It is especially difficult to weld castings that have been in elevated temperature service because of embrittlement. 2.2.2 Iron-chromium-nickel alloy types HD and HE have two-phase austenite-ferrite microstructures containing chromium carbides. They have substantially better ductility as-cast than the iron-chromium HC type but will become embrittled upon long exposure to temperatures around 1500oF (816oC) through formation of the sigma phase. Ductility of the alloys can be restored by heating them to the range 1800 - 2000oF (982 - 1093oC) and cooling rapidly to below 1200oF (649oC). It is unnecessary to preheat castings for welding and postweld heat treatment is required only for relief of welding stresses in complicated sections. The HF, HH, HI, HK and HL grades, as normally made, have a microstructure of carbides in a wholly austenitic matrix. The HH and HI alloys are borderline and unless balanced to be wholly austenitic will contain some ferrite. Ferrite-free compositions are preferred for high temperature strength and less susceptibility to sigma formation. Because increase in carbon content tends to decrease the microfissuring of wholly austenitic welds, the alloys with carbon at the higher end of the composition range are somewhat easier to weld than those on the low side. Furthermore, welding filler metal

matching the carbon content of the cast alloys is available and is preferred to the lowcarbon, partially ferritic type used for welding corrosion resistant alloys since it provides high temperature strength comparable to the base metal. 2.2.3 Iron-nickel-chromium alloys in which the nickel content exceeds the chromium are grades HN, HT, HU, HW and HX. They are wholly austenitic in microstructure and contain substantial amounts of carbides but do not form sigma phase under any conditions. The ratio of silicon to carbon is important to the weldability of these alloys especially the HT and HU grades. Depending on the actual silicon and carbon contents, a ratio in the general neighborhood of 2:1 is considered to give the best balance between weld soundness and ductility. With sufficiently high carbon, the weld is sound at any silicon level but ductility decreases as carbon content increases. Ductility falls off sharply at high silicon-low carbon ratios and welds are badly fissured. Welding electrodes and filler metal that create weld deposits having silicon and carbon ion the ranges 0.75 to 1.50 percent and 0.40 to 0.55 percent, respectively, are available and are preferred for successful welds. Preheat is not required for welding these alloys in general, but complex shapes and heavy sections of the HN, HT and HU grades have improved weldability if preheated to around 400oF (204oC). Contamination of the weld by lead, sulfur or phosphorous is also very detrimental to these alloys and the same precautions regarding cleaning of the weld zone should be observed as described for the high nickel corrosion resistant grades in Section 2.1.4. 2.3 Welding dissimilar metals Welds between different high alloys or between a high alloy and low alloy or carbon steel, can be made successfully with most of the heat and corrosion resistant grades. When such welds are attempted, the effects of dilution of the filler metal in the weld deposit must be given attention. The microstructure in the weld zone between a wholly austenitic and ferritic alloy, for example, will be different from either of the base materials and will have properties determined by the chemical composition balance of the diluted metal. Prediction of the structure to be expected can be obtained form the Schaeffler diagram. (See items 3 and 12 in the Bibliography.) Filler metals of higher alloy content than the high alloy base metal. are often used when welding high alloys to carbon steel. The use of carbon or low alloy steel filler metal on high alloys must be avoided since brittle, crack-prone welds will result. In order to prevent martensite formation in the weld zone under conditions of restraint, the low alloy should first be “buttered” with a layer of high alloy weld metal which should subsequently be shaped to provide the weld groove. The high alloy piece than can be welded to this prepared groove by using the normal filler metal. 3. Welding as a casting production and utilization process Few processes are more important to the production and utilization of high alloy castings than welding. Although it may be obvious why welding is an important means for incorporating castings into composite structures (pipe lines, for example, where mechanical connections are undesirable), it may seem a misnomer to call welding a foundry “production process”. Welding frequently is looked on as just a repair technique whereby defective castings are salvaged. It is implied, therefore, that improved foundry

practices would result in production of defect-free castings and obviate the need for weld repair. Such a viewpoint overlooks the fact that the use of welding in casting production is dictated largely by specification requirements of the user and by the casting design. 3.1 Surface irregularities on castings are inherent in varying degree in the available molding processes. The foundry often can offer a choice of manufacturing methods and, where relative freedom from surface irregularities is desired, the purchaser’s selection may then be based on economic considerations. If warranted by a large quantity of pieces and savings in cost to the purchaser on subsequent manufacturing processes in his operation, a casting technique requiring the most costly pattern equipment may be selected with the result that little or no welding on the surface of the castings will be involved. On the other hand, if the least costly molding method is chosen, then welding becomes a production tool for the “cosmetic” improvement of surface quality by elimination of excessive irregularities or for the structural rebuilding of surface discontinuities. Where surfaces are machined, machining is the production tool for the improvement of the surface finish, yet it is seldom, if ever, considered a “salvage” or “repair” operation. On occasion, both welding and machining may be required if rough machining discloses shallow sub-surface voids. 3.2 The relative versatility of the casting process among the various methods for producing desired shapes, leads many designers into the belief that any configuration, no mater how complex, should be castable with all sections completely free of internal voids or inclusions. Such is not the case, however, so that if the casting design makes it impossible to feed every portion of the mold effectively, unacceptable shrinkage must be corrected by the deposition of weld metal to fill the voids. 3.2.1 Preparation fo welding involves removal of metal inward from the surface of the as-cast section to eliminate the internal shrinkage or non-metallic inclusion. The cavity is then inspected to determine that all “unsound” metal has been removed before the section is rebuilt with layers of weld beads. This inspection may be visual or it may be specified to be done by radiographic or dye penetrant examination. What constitutes removal of porosity or inclusions to “sound” base metal is subject to interpretation and should be a matter of agreement between the purchaser and the foundry. Visual determination that unsound metal has been removed is usually considered sufficient to allow welding to proceed. If dye penetrant or radiographic examination is required the same criteria of acceptability are often applied to the prepared cavity as those applying (or which would apply, if specified) to the casting a s a whole. 3.2.2 Where design considerations prevent the proper feeding of casting sections, an otherwise uneconomical or impractical configuration may become feasible by welding together several less complex components. When the structure is assembled from two or more smaller and simpler castings, production of the individual parts can be arranged for optimum soundness, and higher over-all quality achieved than possible with a onepiece casting. It is obviously more economical to weld sound cast sections to one another in a preplanned fashion than to search for an internal void by non-destructive

inspection, to remove good as-cast metal in order to get to the flaw, and then rebuild the section with weld metal. The usefulness of cast-weld construction, however, is not confined to exceptionally large or complex castings. Economies also can be obtained, for example, where a part is too big to be machine-molded in one piece but which can be divided into two machine-molded castings and then reunited by welding. For large structures that require machining in only one area, it is sometimes advantageous to cast and machine that portion separately and afterward to weld the two parts together. 3.3 Quality of welds in most of the high alloy types is not affected by the size of the sections or the cavity dimensions. Thus the distinction between so-called “minor” and “major” welds has no real significance and is often over-emphasized in purchase specifications. The strength of properly made welds is equivalent to that of the base metal (if the filler metal used creates a weld deposit of the same alloy composition) so that arbitrary limitations on the amount of welding permitted on castings, or timedelaying inspection and approval requirements prior to welding, are both costly and frequently unnecessary. 4 Welding processes in general use for high alloy castings Cast high alloys can be welded by electric arc, electroslag, and oxyacetylene processes. The great majority of welds are made by arc-welding techniques and of these the shielded metal-arc process is the most popular. All the processes provide protection of the metal from the atmosphere during welding which is essential to ensure quality of the weld. The type of weld to be made and the characteristics of the alloy being welded, however, are influential in the choice of welding process to be employed. 4.1 detailed descriptions of the equipment used in each process, suggested joint designs, and discussions of each welding technique, are contained in equipment manufacturers’ literature and in several of the references listed in the appended bibliography. The appropriate chapters in Volume 6 “Welding and Brazing” of the Metals Handbook, Eight Edition, published by the American Society of Metals, are especially informative. The following comments, therefore, are confined to the application of the processes to high alloy castings. 4.1.1 Shielded metal-arc process Used for repair and fabrication welding on both corrosion and heat resistant alloy types, this process is adaptable to many of the situations encountered in casting manufacture or assembly. Electrodes are available in small or large quantities for all alloy compositions. It is a manual process that lends itself to wide variation in size and configuration of welds and to conditions of shop or filed welding. The slag developed during welding is a drawback, however, since it may result in weld inclusions and must be cleaned carefully from each bead before deposition of the next one. Although in carbon steel weld slags on one bead may sometimes be “floated out” through the next pass, this cannot be relied on in high alloys. Considerable skill is required of the operator in control of the arc and weld metal. Electrode coatings must be guarded against pick up of moisture in order to minimize pinholing.

4.1.2 Gas metal-arc process Known frequently as “MIG” welding but currently designated as “GMAW” by the American Welding Society, this process is used mainly for fabrication welding where advantage can be taken of the high speed and relatively long periods of welding made possible by the continuous feeding of filler metal in the form of uncoated wire. Shielding of the weld by an inert gas practically eliminates development of slag, but slag can be formed by reactions within the molten pool so that cleaning of each weld pass is advisable. In addition to fabrication welding, the process is used for repair welding of some alloy types as noted on the individual welding procedure sheets. The need for protection of the shielding gas from drafts and reduced portability of the equipment make this process less attractive tan shielded metal-arc welding or gas tungsten-arc welding fo casting repair. 4.1.3 Gas tungsten-arc process Like the gas metal-arc process described earlier, gas tungsten-arc (TIG or GTAW) uses an inert gas to protect the weld zone from the atmosphere but heat for fusion is provided by an arc between the casting and a non-consumable tungsten electrode. Thus welds can be made merely by fusion of the base metal without the addition of filler metal, or filler metal, if needed, may be added as bare wire. High heating rates and low heat inputs are characteristic of the tungsten arc which is especially desirable in welding in welding corrosion resistant alloys, particularly where postweld heat treatment is inconvenient. For this reason many superficial welds are made by this process. Gas tungsten-arc welding is also used for the root pass of fabrication welds because of the excellent visibility of the weld pool to the operator and the high quality of welds obtained. Subsequent passes often are laid down by other processes where large welds are involved. The process suffers from the same disadvantage as the gas metal-arc in that the weld zone must be protected from drafts that might dilute the shielding gas and cause inferior weld quality. 4.1.4 Electroslag welding This process is used almost exclusively for the production of fabrication welds joining very large and heavy-walled castings where considerable quantities of metal are required in the joint. Filler metal is added through an electrically conductive molten slag which melts the surface of the base metal, and the entire weld pool is retained by watercooled copper shoes bridging the joint on each side of the pieces being welded. This requires extensive auxiliary equipment for positioning the castings and for automatically feeding the filler metal to the weld. The process is used for high alloys, but because of its limited application, no welding procedure sheets are being issued. 4.1.5 Oxyacetylene welding Welding using the flame of a torch burning a mixture of oxygen and acetylene gases to heat the work and simultaneously protect the weld pool from the air can be done on high alloy castings. As in the GTAW process, filler metal is added to the weld in the form of bare wire. The process is never advisable for use with the corrosion resistant alloys because of the pick up of carbon from the flame which reduces the corrosion resistance of the weld. This is not a serious factor with high-chromium, heat resistant

alloy types, but oxyacetylene welding has no advantage over electric are welding which has almost completely superseded it commercially. 4.2 Individual alloy welding procedures The following pages covering individual alloy types provide specific welding procedure information for may of the standard grades of corrosion resistant and heat resistant casting alloys. Some general comments are in order regarding the production of good welds on high alloy castings and their acceptability. Proper training of welders is essential. Safety precautions should be observed. These are covered by American National Standard Z 49.1, “Safety in Welding and Cutting”. For many types of construction, compliance must be established with the Boiler and Pressure Vessel Code and the American National Standard Code for Pressure Piping both of which are published by the American Society of Mechanical Engineers. The qualification of welders and welding procedures necessary to meet the requirements of these codes are set forth in Section IX of the ASME Boiler and Pressure Vessel Code. Care must be taken to keep the coatings on coated electrodes free from moisture. Once the container in which such electrodes are received is opened, the coating may absorb water from the atmospheric humidity and a porous weld deposit may result. Several hours exposure to high humidity can raise the coating moisture to a detrimental level. For this reason, unused electrodes should be stored at 200oF (93oC) or higher. Electrodes from freshly opened packages are considered best for critical welds. The coatings on electrodes (for direct current welding) can be either the lime of titania type. A large, hot arc pool is characteristic of the lime coatings and the slag freezes quickly. Titania coatings which can be used for either AC or DC welding are distinguished by small arc puddles and a thin, low viscosity slag. Although welds made with titania-coated electrodes have generally smoother surfaces than those made with the lime-coated types, and slag that is easier to remove, lime coatings give better weld pool protection and are more frequently used for welding cast high alloys. The need for cleanliness for the surfaces of prepared cavities or joints cannot be over emphasized. Cleaning of the entire weld zone before, during and after welding is essential to successful welding of high alloy castings. Contamination of the weld itself or the adjacent base metal can seriously affect the performance of the casting in service. The requirements for postweld heat treatment as set forth in Section 12 of the individual alloy welding procedures should be given careful attention. A weld zone that is mechanically sound may be unfit for its intended service if it has not been restored to a microstructure having adequate corrosion resistance. Bibliography For additional information on the subjects covered in the foregoing review, the reader

will find details in the following references: 1. R.D. Thomas, Jr., “Crack Sensitivity of Chromium-Nickel Stainless Steel Weld Metal”, Metal Progress, 50, pp 474 - 479, September, 1946 [Advantages of ferritic limecoated electrodes, danger of changes in weld metal composition from dilution by base metal] 2. D. Rozet, H.C. Campbell and R. D. Thomas, Jr., “Effect of Weld Metal Composition on the Strength and Ductility of 15%Cr - 35%Ni Welds”, Welding Journal, 13, No. 10, pp 481-s to 491-s, 1948 [Importance of Si/C ratio] 3. A.L. Schaeffler, “Constitution Diagram for Stainless Steel Weld Metal”, Metal Progress, 56, pp 680 - 680B, November 1949 [Determination of ferrite content from chemical composition of an alloy] 4. E.M. Anger, W.E. Dundin and G. Thompson “How to Weld High Alloy Castings”, The Welding Engineer, April, May and September, 1953 5. Anon., “Welding Cracks in Columbium - Bearing Stainless Steel”, Metal Progress, 67, pp 109 - 111, May 1955 [cracking in type 347 reduced by 4 - 8 percent ferrite] 6. W. Hirsch and H.W. Fritze, “The Hot Cracking of Austenitic Chromium-Nickel Steel Welds”, Scweissen und Schneiden, 8, No. 3, 1956 [Columbium favors cracking of austenite by forming an austenite - FeCb eutectic; cracking does not occur if ferrite is present] 7. B.I. Medovar and Yu. B. Malevsky, “The Effect of Chemical Composition of Austenitic 25-20 Weld Metal on the Gamma-Sigma Transformation”. Welding Production (Russian), April 1959 [Increase of carbon to 0.20 percent suppresses sigma formation] 8. J.C. Borland and R.N. Younger, “Some Aspects of Cracking in Welded Cr-Ni Austenitic Steels”, British Welding Journal, January, 1960 [Extensive bibliography on subject from 1920 to 1959] 9. R.W. Emerson, R.W. Jackson and C.A. Dauber, “Transition Joints Between Austenitic and Ferritic Steel Piping for High Temperature Steam Service”, Welding Journal, 27, No.9, pp 385-ss to 393-s, 1962 [Use of higher alloy filler metal] 10. R.M. Evans, “Joining of Nickel-Base Alloys, DMIC Report 181, December 20, 1962 11. E.A. Schoefer, “ACI Data Sheets”, Steel Founders’ Society of America [Chemical, physical and mechanical properties of corrosion and heat resistant cast alloys] 12. H.C. Campbell, “Identifying Corrosion and Welding Failures in Stainless Steels”,

Materials Protection, NACE, October 1963 [Distinction between failure of a weld due to its corrosion resistance or to its mechanical characteristics] 13. D.M. Haddrill and R.G. Baker, “Microcracking in Austenitic Weld Metal”, British Welding Journal, August 1965 [Higher carbon in weld reduces cracking] 14. F.C. Hull, “Effects of Delta Ferrite on the Hot Cracking of Stainless Steel”, Welding Journal, 46, No.9, pp 399-s to 490-s 1967 [Ferrite-austenite grain boundaries are not wet by last freezing liquid and hence sustain contraction stresses imposed by restraint; whereas austenite-austenite grain boundaries are so wet and, therefore, cannot resist contraction and cracking results. 5-10 percent ferrite the preferred range] 15. G.E. Linnert, “Weldability of Austenitic Stainless Steel as Affected by Residual Elements”, ASTM Special Technical Publication No. 418, July, 1967 [Possibility of slag formation from reactions within the weld pool] 16. G.E. Linnert, “Welding Characteristics of Stainless Steels”, Metals Engineering Quarterly, ASM, 7, No. 4, pp 16-41 [Details of welding processes and techniques] 17. R.P. Sullivan, “Fusion Welding of Stainless Steel”, Ibid., pp 16 - 41 [Details of welding processes and techniques] 18. K.A. Ebert, “Influencing the Weldability of Austenitic Chromium Nickel Steels by Means of Their Ferrite Contents”, Schweissen und Schneiden, 20, No.2, 1968 [Ferrite is location of precipitated phosphorus, silicon, carbon, etc. in preference to austenite grain boundaries and thus reduces crack sensitivity of weld] 19. American Welding Society Specifications for Electrodes: AWS A5.4-69; AWS A5.969; AWS A5.11-69; AWS A5.12-69; AWS A5.14-69; also “Terms and Definitions”, AWS A3.0-69 20. W.T. Delong, “Calibration Procedure for Instruments to Measure the Delta Ferrite Content of Austenitic Stainless Weld Metal”, published by High Alloys Committee of the Welding Research Council, July 1972 21. American Welding Society Handbook, Section IV, Fifth Edition, 1966, Chapters 64 and 65, “Metals and Their Weldability” 22. American Society for Metals Metals Handbook, Vol. 6, Eighth Edition, “Welding and Brazing”, 1971

Shielded Metal-Arc (SMAW)

Procedure followed by experienced producers of high alloy castings in welding of type CA6NM alloy as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy type CA6NM (11.5-14 Cr, 3.5-4.5 Ni, .40-1.0 Mo) static and centrifugal castings.

2

Filler Metal AWS E410 Ni Mo-15 AWS E410 Ni Mo-16

Lime coated electrode is preferred for DC welding. (This rod should not be used for AC.) Titania coated electrode is preferred for AC welding and may be used for DC. This type rod is useful for welding positions other than vertical-down.

3

Position Whenever possible, all welding is done in the "flat" position. A ±15° angle of the groove with the horizontal plane normally is considered flat.

4

Base Metal Preparation for Repair Defects are removed before attempting any repair. Defect removal is accomplished by arc-air, chipping, gouging, grinding or machining, or by some combination of these operations. Defect removal to sound base metal is assured by the use of one or more of the following inspection processes: Visual, dye penetrant, or radiography. Where dye penetrant or radiographic inspection of a prepared cavity discloses shrinkage of a severity not in excess of that specified for the castings as a whole, acceptable practice is to weld such areas without further preparation (3.2.1).

5

Base Metal Preparation for Fabrication Parts to be fabricated by welding are shaped to provide a groove when placed together. The mating areas are either cast to shape and then ground, or ground or machined so that a good fit of the welding groove can be obtained. Good practice is to machine dry with no lubricant. Components are thoroughly cleaned before assembly. Alcohol and acetone are solvents frequently used for cleaning.

6

Preheat Temperature CA6NM can normally be welded at room temperature (70°F) (21°C). For large welds in heavy or highly stressed sections, castings may be preheated in the range of 212 to 300°F (100 to 150°C), and the interpass temperature may be maintained at 500 to 600°F (260 to 315°C) as a guideline. Welding of castings in the heat treated condition is preferred to welding as-cast metal.

7

Section Size Section size normally is considered unimportant in welding this alloy. If section thickness is under ½ inch, it may be desirable to limit electrode size to 1/8 inch maximum. For section thicknesses over three inches, preheating may be employed.

8

Cavity Dimensions Cavity dimensions are not critical. A minimum included angle of 30° (included angles up to 90° sometimes are used) should be maintained between the sides of the cavity, and a root radius of 3/16 to 1/4 inch should be provided to allow full access to the root.

9

Welding Techniques Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to two to three times the electrode wire diameter, or twice the gas cup orifice diameter. All slag is removed between passes with a hammer and a stainless wire brush, or a needle gun. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, one 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions.

10

Electrical Characteristics Welding normally is done using DC reverse polarity. Electrode sizes from 3/32 to 3/16 inch may be used with the current and voltage suggested by the electrode manufacturer's specifications for the particular size rod. Due to the high electrical resistance of stainless steel, the burn-off rate of the electrode is higher than for carbon steel. Arc length should be maintained as short as possible. A short arc length is very important when starting a weld pass since a long arc can sometimes be caused by initial hand recoil and may result in weld spatter or porosity.

11

Technique for Welding Machined Castings No special technique (9) is necessary for welding machined castings; it is good practice to use small diameter electrodes and low heat to prevent distortion.

12

Post-Weld Heat Treatment Welds normally are heated to the range 1100-1150°F (593-620°C) and then air cooled. In cases where a special hardness requirement must be attained, the welded casting is given a full reheat treatment followed by tempering.

13

Non-Destructive Tests Welds are tested for quality by one or more of the following methods of inspection: Visual, liquid penetrant, magnetic particle, radiography, ultrasonic, or pressure.

14

Summary To produce welds that will satisfy the user's requirements, take the following precautions: 1.

Make sure that all defects have been removed to sound base metal (4), and that surfaces to be welded are thoroughly cleaned (5 and 9).

2.

Use the proper filler metal (2).

3.

Use a welding technique (9) which will produce welds free of porosity, undercutting or lack of penetration.


Procedure followed by experienced producers of high alloy castings in welding of types CA15 and CA40 alloys as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy type CA15 (11.5-14 Cr, 0.15 max. C) static and centrifugal castings.

2

Filler Metal AWS E410-15 AWS E410-16

Lime coated electrode is preferred for DC welding. (This rod should not be used for AC.) Titania coated electrode is preferred for AC welding and may be used for DC. This type rod is useful for welding positions other than vertical-down.

3

Position Whenever possible, all welding is done in the "flat" position. A ±15° angle of the groove with the horizontal plane normally is considered flat.

4

Base Metal Preparation for Repair Defects are removed before attempting any repair. Defect removal is accomplished by arc-air, chipping, gouging, grinding, or machining, or by some combination of these operations. Defect removal to sound base metal is assured by the use of one or more of the following inspection processes: Visual, dye penetrant, or radiography. Where dye penetrant or radiographic inspection of a prepared cavity discloses shrinkage of a severity not in excess of that specified for the casting as a whole, acceptable practice is to weld such areas without further preparation (3.2.1).

5


6

Preheat Temperature Heat this alloy to the range 300-600°F (149-315°C) and maintain the metal above 300°F (149°C) during the welding operation. Welds sometimes are made successfully without preheat, especially if the carbon content of the alloy is less than 0.10 percent. In general, preheat is preferred. Heating in the range 600-1100°F (315-593°C) is avoided because it will result in a loss of ductility and impact strength. Welding of castings in the annealed condition is preferred to welding of as-cast metal.

7

Section Size Section size usually is considered unimportant in welding this alloy. If section thickness is under ½ inch, it may be desirable to limit electrode size to 1/8 inch maximum. For section thicknesses over three inches, preheat temperature should be at the high end of the range.

8

Cavity Dimensions Cavity dimensions are not critical. A minimum included angle of 30° (included angles up to 90° are sometimes used) should be maintained between the sides of the cavity, and a root radius of 3/16 to 1/4 inch should be provided to allow full access to the root.

9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to two to three times the electrode wire diameter. All slag is removed between passes with a hammer and a wire brush, or a needle gun using stainless steel needles. No peening is done unless the welds are large and/or the cavity or weld groove is deep. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. Tack welding should be performed after the casting has been preheated in order to minimize the possibility of initiating a crack at the tack weld (6 and 7).

10

Electrical Characteristics Welding normally is done using DC reverse polarity. Successful welds can be made, however, using AC. Electrode sizes from 3/32 to 3/16 inch may be used with the current and voltage suggested by the electrode manufacturer's specifications for the particular size rod. Due to the high electrical resistance of stainless steel, the burn-off rate of the electrode is higher than for carbon steel. Arc length should be maintained as short as possible. A short arc length is very important when starting a weld pass since a long arc sometimes can be caused by initial hand recoil and may result in weld spatter or porosity.

11

Technique for Welding Machined Castings This process can be used for welding machined castings by keeping heat to a minimum through use of small electrodes, and by cooling to room temperature between passes. Type AWS E309-15 or AWS E310-15 electrodes sometimes are used.

12

Post-Weld Heat Treatment Welds usually are heated to the range 1100-1450°F (593-788°C), and then either air or furnace cooled depending on the specification of mechanical properties for the casting. In some cases where welds are large or located in critical areas of the casting, they are given a full re-heat treatment of heating to 1800°F (982°C) minimum, followed by air cooling and tempering at the specified temperature. Minor, superficial welds sometimes are not post-heat treated when the presence of hard spots resulting from untempered martensite in the weld deposits can be tolerated.

13

Non-Destructive Tests Welds are tested for quality by one or more of the following methods of inspection: Visual, dye penetrant, magnetic particle, radiography, pressure, or ultrasonic.

14



2.


3.


Gas Metal-Arc (GMAW)


Subject/Procedure

1


2

Filler Metal AWS ER410 - Bare wire is used in this process.

3

Position All welding is done in the "flat" position. A ±15° angle of the groove with the horizontal plane normally is considered flat.

4

Base Metal Preparation for Repair Defects are removed before attempting any repair. Defect removal is accomplished by arc-air, chipping, gouging, grinding or machining, or by some combination of these operations. Defect removal to sound base metal is assured by the use of one or more of the following inspection processes: Visual, dye penetrant, or radiography. Where dye penetrant or radiographic inspection of a prepared cavity discloses shrinkage of a severity not in excess of that specified for the casting as a whole, acceptable practice is to weld such areas without further preparation (3.2.1).

5


6


7

Section Size Section size usually is considered unimportant in welding this alloy. For section thicknesses over two inches, preheat should be above 400°F (204°C).

8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result

in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to about the diameter of the gas nozzle. No peening is done. It is customary to remove any defects in the weld by grinding before laying down the next bead. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. Tack welding should be performed after the casting has been preheated in order to minimize the possibility of initiating a crack at the tack weld (6 and 7). 10

Electrical Characteristics Welding is done using DC reverse polarity. Wire diameter range is from 0.035 to 0.094 inch. Currents and voltages suggested by the manufacturer's specifications for the wire size used are normally followed. Shielding gas is usually argon plus two percent (2%) oxygen at a flow rate of 30 to 50 cfh. An alternate mixture of 75 percent argon plus 25 percent carbon dioxide at a flow rate of 20 cfh also is used.

11

Technique for Welding Machined Castings This process is seldom used to weld machined castings; when it is, AWS ER309 or AWS ER310 type electrode wire is used.

12

Post-Weld Heat Treatment Welds usually are heated to the range 1100-1450°F (593-788°C), and then either air or furnace cooled depending on the specification of mechanical properties for the casting. In some cases where welds are large or located in critical areas of the casting, they are given a full re-heat treatment of heating to 1800°F (982°C) minimum, followed by air cooling and tempering at the specified temperature. Minor, superficial welds sometimes are not post-heat treated when the presence of hard spots resulting from untempered martensite in the weld deposits can be tolerated.

13


14



2.


3.


Gas Tungsten-Arc (GTAW)


Subject/Procedure

1


2

Filler Metal AWS ER410 - Bare wire is used to weld this alloy.

3

Position Whenever possible, all welding is done in the "flat" position. A ±15° angle of the groove with the horizontal plane normally is considered flat. Successful welds can be made by this process, however, in all positions.

4

Base Metal Preparation for Repair Defects are removed before attempting any repair. Defect removal is accomplished by grinding. Defect removal to sound base metal is assured by the use of one or more of the following inspection processes: Visual, dye penetrant, or radiography.

5


6


7

Section Size Section size usually is considered unimportant in welding this alloy.

8

Cavity Dimensions This process is used mainly for surface welds, hence very little metal excavation is necessary and dimensions are not critical.

9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is not restricted in extent. Peening may be done between successive passes on deep welds. If parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. Tack welding should be

performed after the casting has been preheated in order to minimize the possibility of initiating a crack at the tack weld (6). 10

Electrical Characteristics Welding is done using DC straight polarity. A non-consumable electrode made of thoriated tungsten (EWTh-2) is used. A high frequency method of starting the arc is preferred over a "scratch start" to avoid tungsten contamination of the weld. The arc should not be struck on a carbon block. Currents and voltages suggested by the manufacturer's specifications for the electrode size used normally are followed. Where filler metal is used, wire sizes range from 1/16 to 3/16 inch. Either helium or argon may be used for the inert shielding gas, but argon is preferred with a flow of 20 to 50 cfh.

11

Technique for Welding Machined Castings No special technique (9) is necessary for welding machined castings; it is good practice, however, to use small rods and low heat to avoid distortion.

12

Post-Weld Heat Treatment Welds usually are heated to the range 1100-1450°F (593-788°C), and then either air or furnace cooled depending on the specification of mechanical properties for the casting. In some cases where welds are large or located in critical areas of the casting, they are given a full re-heat treatment of heating to 1800°F (982°C) minimum, followed by air cooling and then tempering at the specified temperature. Minor, superficial welds often are not post-heat treated.

13


14



2.


3.



Procedure followed by experienced producers of high alloy castings in welding of type CB7Cu alloy as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy types CB7Cu-1 (15.5-17.0 Cr, 3.6-4.6 Ni, 2.5-3.2 Cu, 0.07 max. C) and CB7Cu-2 (14.0-15.5 Cr, 4.5-5.5 Ni, 2.5-3.2 Cu, 0.07 max. C) static and centrifugal castings.

2


Lime coated electrode is preferred for DC welding. This rod should not be used for AC. Titania coated electrode is used for AC welding and may be used for DC.

3


4


5


6

Preheat Temperature Normally this alloy is not preheated; however, if the section size is over 3/4 inch in thickness, and the extent of the weld substantial, the alloy may be preheated to 500°F (260°C).

7

Section Size Section size usually is considered unimportant in welding this alloy. Thick sections may require preheat (6) for satisfactory welds.

8


9


in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to two and one-half times the electrode diameter. Fully hardened castings are frequently preheated (6) and welded with low heat and small rods. No peening is done. All slag is removed with a stainless steel wire brush or slagging hammer, or needle gun using stainless steel needles. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. Tack welding should be performed after the casting has been preheated in order to minimize the possibility of initiating a crack at the tack weld (6 and 7). 10

Electrical Characteristics Welding normally is done using DC reverse polarity. Successful welds can be made, however, using AC. Electrode sizes from 3/32 to 1/4 inch may be used with the amperage and voltage suggested by the electrode manufacturer's specifications for the particular size rod. Due to the high electrical resistance of stainless steel, the burn-off rate of the electrode is higher than for carbon steel. Arc length should be maintained as short as possible. A short arc length is very important when starting a weld pass since a long arc can sometimes be caused by initial hand recoil and may result in weld spatter or porosity.

11

Technique for Welding Machined Castings No special technique (9) is necessary for welding machined castings; it is good practice, however, to use small rods and low heat to avoid distortion. If the welded area will be subject to corrosion, it is desirable to quench the weld zone with a wet cloth between each pass. For small welds on heavy sections, this may not be necessary since the heavy mass will tend to cool the weld zone rapidly.

12

Post-Weld Heat Treatment Both annealed and aged type CB7Cu castings can be restored to specified hardness by low temperature postweld hardening treatment in the range 900-1100°F (482-593°C). But to restore hardenability properties to multiple-pass welds on heavy sections, they are heated to the range 1850-1950°F (1010-1066°C), held until uniformly at temperature, rapidly cooled by quenching in water, oil or air, and followed by the desired aging treatment. Single-pass welds usually do not require postweld solution heat treatment.

13

Non-Destructive Tests Welds are tested for quality by one or more of the following methods of inspection: Visual, dye penetrant, radiography, or pressure.

14



2.


3.




Subject/Procedure

1


2

Filler Metal AWS ER630

Bare wire is used.

3


4

Base Metal Preparation for Repair Defects are removed before attempting any repair. Defect removal is accomplished by arc-air, chipping, gouging, grinding or machining, or by some combination of these operations. Defect removal to sound base metal is assured by the use of one or more of the following inspection processes: Visual, dye penetrant, or radiography. Where dye penetrant or radiographic inspection of a prepared cavity discloses shrinkage of a severity not in excess of that specified for the casting as a whole, acceptable practice is to weld such areas without further preparation (3.2.1.).

5


6


7


8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to two and one-half times the wire diameter. No peening is done. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch

backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. Tack welding should be performed after the casting has been preheated in order to minimize the possibility of initiating a crack at the tack weld (6 and 7). 10

Electrical Characteristics Welding normally is done using DC reverse polarity. Successful welds can be made, however, using AC. Electrode sizes from 3/64 to 3/32 inch may be used with the current and voltage suggested by the electrode manufacturer's specifications for the particular size rod. Due to the high electrical resistance of stainless steel, the burn-off rate of the electrode is much higher than for carbon steel. Arc length should be maintained as short as possible. A short arc length is very important when starting a weld pass since a long arc sometimes can be caused by initial hand recoil and may result in weld spatter or porosity. Shielding gas is usually argon plus two percent (2%) oxygen at a flow rate of 30 to 50 cfh.

11

Technique for Welding Machined Castings No special technique (9) is necessary for welding machined castings; however, use small rods and low heat to avoid distortion. If the welded area will be subject to corrosion, quench the weld zone with a wet cloth between each pass. For small welds on heavy sections, this may not be necessary since the heavy mass will tend to cool the weld zone rapidly.

12

Post-Weld Heat Treatment Both annealed and aged type CB7Cu castings can be restored to specified hardness by low temperature postweld hardening treatment in the range 900-1100°F (482-593°C). But to restore hardenability properties to multiple-pass welds on heavy sections, they are heated to the range 1850-1950°F (1010-1066°C), held until uniformly at temperature, rapidly cooled by quenching in water, oil or air, and followed by the desired aging treatment. Single pass welds usually do not require postweld heat treatment.

13


14



2.


3.




Subject/Procedure

1


2


Bare wire is used. For repair of small surface irregularities, welds are sometimes made without the use of any filler metal.

3


4


5


6


7


8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used, but very little weaving is done. No peening is done. Because no slag is formed during the welding

operation, interpass cleaning is not necessary. If parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. Tack welding should be performed after the casting has been preheated in order to minimize the possibility of initiating a crack at the tack weld (6 and 7). 10

Electrical Characteristics Welding is done using DC straight polarity. A non-consumable electrode made of thoriated tungsten (EWTh-2) is used. A high frequency method of starting the arc is preferred over a "scratch start" to avoid tungsten contamination of the weld. The arc should not be struck on a carbon block. Currents and voltages suggested by the manufacturer's specifications for the electrode size used are normally followed. Where filler metal is used, wire sizes range from 1/16 to 3/16 inch. Either helium or argon may be used for the inert shielding gas, but argon is preferred with a flow of 15 cfh.

11

Technique for Welding Machined Castings No special technique (9) is necessary for welding machined castings; however, use small rods and low heat to avoid distortion. If the welded area will be subject to corrosion, quench the weld zone with a wet cloth between each pass. For small welds on heavy sections, this may not be necessary since the heavy mass will tend to cool the weld zone rapidly.

12

Post-Weld Heat Treatment Both annealed and aged type CB7Cu castings can be restored to specified hardness by low temperature postweld hardening treatment in the range 900-1100°F (482-593°C). But to restore hardenability properties to multiple-pass welds on heavy sections, they are heated to the range 1850-1950°F (1010-1066°C), held until uniformly at temperature, rapidly cooled by quenching in water, oil or air, and followed by the desired aging treatment. Single pass welds usually do not require postweld heat treatment.

13


14



2.


3.



Procedure followed by experienced producers of high alloy castings in welding of type CD4MCu alloy as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy type CD4MCu (24.5-26.5 Cr, 4.75-6 Ni, 1.75-2.25 Mo, 2.75-3.25 Cu, 0.04 max. C) static and centrifugal castings.

2

Filler Metal Lime coated electrodes that will deposit weld metal of the CD4MCu composition are available and are used. The weld deposit should approximate the base metal because the properties of this alloy are influenced critically by the chemical composition, however, some minor variation in composition may be necessary to obtain the desired microstructure.

3

Position All welding is done in the "flat" position. A ± 15° angle of the groove with the horizontal plane normally is considered flat.

4


5

Base Metal Preparation for Fabrication Parts to be fabricated by welding are shaped to provide a groove when placed together. The mating areas are either cast to shape and then ground, or ground or machined so that a good fit of the welding groove can be obtained. Good practice is to machine dry with no lubricant. Components are thoroughly cleaned before assembly.

6

Preheat Temperature No preheat is required for type CD4MCu alloy.

7


8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to two to three times the electrode wire diameter. No peening is done. All slag is removed between passes with a hammer and/or a stainless steel wire brush. If a defect

penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. This alloy cannot be welded satisfactorily to other metals. 10

Electrical Characteristics Welding normally is done using DC reverse polarity. Electrode sizes from 3/32 to 3/16 inch may be used with the current and voltage suggested by the electrode manufacturer's specifications for the particular size rod. Due to the high electrical resistance of stainless steel, the burn-off rate of the electrode is much higher than for carbon steel. Arc length should be maintained as short as possible. A short arc length is very important when starting a weld pass since a long arc can sometimes be caused by initial hand recoil and may result in weld spatter or porosity.

11

Technique for Welding Machined Castings No special technique (9) is necessary for welding machined castings; however, use small rods and low heat to avoid distortion.

12

Post-Weld Heat Treatment To restore maximum corrosion resistance to welded type CD4MCu castings, they are heated to 2050°F (1121°C) minimum, held until uniformly at temperature, furnace cooled to 1900°F (1038°C), and then rapidly cooled by quenching in water, oil or air.

13


14



2.


3.



Procedure followed by experienced producers of high alloy castings in welding of type CD4MCu alloy as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy type CD4MCu (24.5-26.5 Cr, 4.75-6 Ni, 1.75-2.25 Mo, 2.75-3.25 Cu, 0.04 max. C) static and centrifugal castings.

2

Filler Metal Small defects and root passes are sometimes welded by fusion of the base metal only, without the addition of any filler metal. When filler metal is used, it is frequently cast rod of the CD4MCu composition. The weld deposit should approximate the base metal because the properties of this alloy are influenced critically by the chemical composition, however, some minor variation in composition may be necessary to obtain the desired microstructure.

3


4

Base Metal Preparation for Repair Defects usually are removed before attempting any repair. Defect removal is accomplished by grinding. Defect removal to sound base metal is assured by the use of one or more of the following inspection processes: Visual, dye penetrant, or radiography.

5

Base Metal Preparation for Fabrication This process is not being used for fabrications of type CD4MCu castings.

6

Preheat Temperature No preheat is required for type CD4MCu alloy.

7


8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. This alloy cannot be welded satisfactorily to other metals.

10

Electrical Characteristics Welding is done using DC straight polarity. A non-consumable electrode made of thoriated tungsten (EWTh-2) is used. A high frequency method of starting the arc is preferred over a "scratch start" to avoid tungsten contamination of the weld. The arc should not be struck on a carbon block. Currents and voltages suggested by the manufacturer's specifications for the electrode size used are normally followed. Where filler metal is used, wire sizes range from 1/16 to 3/16 inch. Either helium or argon may

be used for the inert shielding gas, but argon is preferred with a flow of 20 to 50 cfh. 11


12

Post-Weld Heat Treatment To restore maximum corrosion resistance to welded type CD4MCu castings, they are heated to 2050°F (1121°C) minimum, held until uniformly at temperature, furnace cooled to 1900°F (1038°C), and then rapidly cooled by quenching in water, oil or air.

13


14



2.


3.



Procedure followed by experienced producers of high alloy castings in welding of type CF8 alloy as reported in a survey of SFSA members Section 1

2

Subject/Procedure Base Metal Alloy type Also types Filler Metal AWS E308-15 AWS E308L-15 AWS E308-16

CF8 (18-21 Cr, 8-11 Ni, 0.08 max. C) static and centrifugal castings. CF3 (17-21 Cr, 8-12 Ni, 0.03 max. C) and CF16F (18-21 Cr, 9-12 Ni, 1.5 max. Mo, 0.20-0.35 Se, 0.16 max. C). Lime-coated electrode is preferred for DC welding. (This rod should not be used for AC.) Used for types CF8 and CF16F. Lime-coated electrode is preferred for DC welding. (This rod should not be used for AC.) Used for type CF3. Titania-coated electrode is used for AC welding and may be used for DC.

3


4


5


6

Preheat Temperature No preheat is required for type CF8 alloy.

7

Section Size Section size usually is considered unimportant in welding this alloy. When sections are under ½ inch in thickness, use an electrode no larger than 1/8 inch.

8


9


in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to two to four times the electrode wire diameter. No peening is done. All slag should be removed between passes with a hammer and/or a stainless steel wire brush, or a needle gun using stainless steel needles. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. 10

Electrical Characteristics Welding normally is done using DC reverse polarity. Successful welds can be made, however, using AC. Electrode sizes from 3/32 to 1/4 inch may be used with the current and voltage suggested by the electrode manufacturer's specifications for the particular size rod. Due to the high electrical resistance of stainless steel, the burn-off rate of the electrode is much higher than for carbon steel. Arc length should be maintained as short as possible. A short arc length is very important when starting a weld pass since a long arc can sometimes be caused by initial hand recoil and may result in weld spatter or porosity.

11

Technique for Welding Machined Castings No special technique (9) is necessary for welding machined castings; however, use small rods and low heat to avoid distortion. If the welded area will be subject to corrosion, quench the weld zone with a wet cloth between each pass. For small welds on heavy sections, this may not be necessary because the heavy mass will tend to cool the weld zone rapidly.

12

Post-Weld Heat Treatment To restore maximum corrosion resistance to welded type CF8 castings, they are heated to 1900°F (1038°C) (2000°F [1093°C] for CF16F and CF20) minimum, held until uniformly at temperature, and then rapidly cooled by quenching in water, oil or air. Small welds which have been made to improve the appearance of casting surfaces that will not be subjected to corrosive attack in service may not require postweld heat treatment. Type CF3 castings may not require postweld heat treatment.

13


14



2.


3.


Gas Metal-Arc (GMAW) Process

Procedure followed by experienced producers of high alloy castings in welding of type CF8 alloy as reported in a survey of SFSA members Section Subject/Procedure 1

2

Base Metal Alloy type Also types Filler Metal AWS ER308L AWS ER308

CF8 (18-21 Cr, 8-11 Ni, 0.08 max. C) static and centrifugal castings. CF3 (17-21 Cr, 8-12 Ni, 0.03 max. C) and CF16F (18-21 Cr, 9-12 Ni, 1.5 max. Mo, 0.20-0.35 Se, 0.16 max. C). Bare wire is used for CF3. Bare wire is used for CF8 and CF16F.

3


4


5


6


7


8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to about ½ inch, or not in excess of the diameter of the gas nozzle. No peening is done. Beads are cleaned between passes with a stainless steel wire brush. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it

extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. 10

Electrical Characteristics Welding is done using DC reverse polarity. Wire diameter range is from 0.035 to 0.094 inch. Currents and voltages suggested by the manufacturer's specifications for the wire size used are normally followed. Shielding gas is usually argon plus two percent (2%) oxygen at a flow rate of 30 to 50 cfh. An alternate mixture of 75 percent argon plus 25 percent carbon dioxide at a flow rate of 20 cfh is also used, but may affect the corrosion resistance of the weld adversely on multipass welds.

11


12


13


14



2.


3.


Gas Tungsten-Arc (GTAW) Process

Procedure followed by experienced producers of high alloy castings in welding of type CF8 alloy as reported in a survey of SFSA members Section Subject/Procedure 1

2

Base Metal Alloy type Also types Filler Metal AWS ER308L AWS ER308

CF8 (18-21 Cr, 8-11 Ni, 0.08 max. C) static and centrifugal castings. CF3 (17-21 Cr, 8-12 Ni, 0.03 max. C) and CF16F (18-21 Cr, 9-12 Ni, 1.5 max. Mo, 0.20-0.35 Se, 0.16 max. C). Bare wire is used for CF3. Small defects and root passes are sometimes welded by fusion of the base metal only, without the addition of any filler metal. Bare wire is used for CF8.

3


4

Base Metal Preparation for Repair Minor, superficial defects are occasionally welded without any preparation other than sandblasting. Defects usually are removed, however, before attempting repair. Removal normally is accomplished by grinding. Defect removal to sound base metal is assured by the use of one or more of the following inspection processes: Visual, dye penetrant, or radiography.

5

Base Metal Preparation for Fabrication This process is seldom used for fabrication of composite castings. It is more frequently used for combining wrought and cast components. Parts to be joined are ground or machined to provide a groove when placed together. Good practice is to machine dry with no lubricant and to clean the parts thoroughly before assembly. A good fit of the mating parts is essential for production of good welds.

6


7

Section Size Section size usually is considered unimportant in welding this alloy. When section thickness is under 1/4 inch, use a copper back-up strip for through welds.

8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited; very little weaving is done in this process. No peening is done and, because no slag is formed during the welding operation, interpass cleaning usually is unnecessary. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in

place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. 10

Electrical Characteristics Welding is done using DC straight polarity. A non-consumable electrode made of thoriated tungsten (EWTh-2) is used. A high frequency method of starting the arc is preferred over a "scratch start" to avoid tungsten contamination of the weld. The arc should not be struck on a carbon block. Currents and voltages suggested by the manufacturer's specifications for the electrode size used are normally followed. Where filler metal is used, wire sizes range from 1/16 to 3/16 inch. Either helium or argon may be used for the inert shielding gas, but argon is preferred with a flow of 20 to 50 cfh.

11


12


13


14



2.


3.



Procedure followed by experienced producers of high alloy castings in welding of type CF8M alloy as reported in a survey of SFSA members Section 1

Subject/Procedure Base Metal Alloy type Also types

2

CF8M (18-21 Cr, 9-12 Ni, 2-3 Mo, 0.08 max. C) static and centrifugal castings. CF3M (17-21 Cr, 9-13 Ni, 2-3 Mo, 0.03 max. C) and CG8M (18-21 Cr, 9-13 Ni, 3-4 Mo, 0.08 max. C).

Filler Metal AWS E308 Mo-15 AWS E316-15 AWS E317-15 *

Lime-coated electrode is preferred for DC welding. (This rod should not be used for AC.)

AWS E316L-15 AWS E308 MoL-15

Used for welding type CF-3M alloy.

AWS E308 Mo-16 AWS E316-16 AWS E317-16 *

Titania-coated electrode is used for AC welding and may be used for DC.

3


4

Base Metal Preparation for Repair Defects are removed before attempting any repair. Defect removal is accomplished by arc-air, chipping, gouging, grinding, or machining, or by some combination of these operations. Defect removal to sound base metal is assured by the use of one or more of the following inspection processes: Visual, dye penetrant, or radiography. Where dye penetrant or radiographic inspection of a prepared cavity discloses shrinkage of a severity not in excess of that specified for the casting as a whole, acceptable practice is to weld such areas without further preparation (3.2.1). * For welding type CG8M castings.

5


6

Preheat Temperature No preheat is required for type CF8M alloy.

7


8

Cavity Dimensions Cavity dimensions are not critical. A minimum included angle of 30° (included angles up

to 90° sometimes are used) should be maintained between the sides of the cavity, and a root radius of 3/16 to 1/4 inch should be provided to allow full access to the root. 9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to two to three times the electrode wire diameter. All slag is removed between passes with a hammer and/or a stainless steel wire brush, or a needle gun using stainless steel needles. No peening is done on most welds, but occasionally light peening of the bead edges may prove beneficial. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions.

10


11

Technique for Welding Machined Castings No special technique (9) is necessary for welding machined castings; however, use small rods and low heat to avoid distortion. If the welded area will be subject to corrosion, it is desirable to quench the weld zone with a wet cloth between each pass. For small welds on heavy sections, this may not be necessary because the heavy mass will tend to cool the weld zone rapidly.

12

Post-Weld Heat Treatment To restore maximum corrosion resistance to welded type CF8M castings, they are heated to 1900°F (1038°C) minimum, held until uniformly at temperature, and then rapidly cooled by quenching in water, oil or air. Small welds which have been made to improve the appearance of casting surfaces that will not be subjected to corrosive attack in service may not require postweld heat treatment. Type CF3M castings may not require postweld heat treatment.

13


14



2.


3.





2


Filler Metal AWS ER308 MoL AWS ER316L

Bare wire is used for CF3M.

AWS ER316 AWS ER308 Mo


AWS ER317

Bare wire is used for type CG8M.

3


4


5


6


7


8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or

weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to about ½ inch, or not in excess of the diameter of the gas nozzle. No peening is done. Beads are cleaned between passes with a stainless steel wire brush. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. 10

Electrical Characteristics Welding is done using DC reverse polarity. Wire diameter range is from 0.035 to 0.063 inch. Currents and voltages suggested by the manufacturer's specifications for the wire size used are normally followed. Shielding gas is usually argon plus two percent (2%) oxygen at a flow rate of 30 to 50 cfh.

11

Technique for Welding Machined Castings No special technique (9) is necessary for welding machined castings; it is good practice, however, to use small rods and low heat to avoid distortion. If the welded area will be subject to corrosion, quench the weld zone with a wet cloth between each pass. For small welds on heavy sections, this may not be necessary because the heavy mass will tend to cool the weld zone rapidly.

12


13


14



2.


3.





2


Filler Metal AWS ER308 MoL AWS ER316L


AWS ER316 AWS ER308 Mo


AWS ER317

Bare wire is used for type CG8M.

Small defects and root passes are sometimes welded by fusion of the base metal only, without the addition of any filler metal. 3


4


5

Base Metal Preparation for Fabrication This process is seldom used for fabrication of composite castings. It is sometimes used for the root pass with subsequent passes laid down by some other process. More frequently, it is used for combining wrought and cast components. Parts to be joined are ground or machined to provide a groove when placed together. A good fit of the mating parts is essential for production of good welds. Good practice is to machine dry with no lubricant and to clean the parts thoroughly before assembly.

6


7


8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited; very little weaving is done in this process. Interpass cleaning usually is not required because no slag is formed unless coated electrodes (even with the coating removed) have been used as filler metal. Any cleaning should be done with a stainless steel wire brush. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions.

10


11

Technique for Welding Machined Castings No special technique (9) is necessary for welding machined castings; however, use small rods and low heat to avoid distortion. If the welded area will be subject to corrosion, it is desirable to quench the weld zone with a wet cloth between each pass. For small welds on heavy sections, this may not be necessary because the heavy mass will tend to cool the weld zone rapidly.

12


13


14



2.


3.



Procedure followed by experienced producers of high alloy castings in welding of type CK20 alloy as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy type CK20 (23-27 Cr, 19-22 Ni, 0.20 max. C) static and centrifugal castings.

2


Lime-coated electrode is preferred for DC welding. (This rod should not be used for AC.) Titania-coated electrode is used for AC welding and may be used for DC.

3


4


5


6

Preheat Temperature No preheat is required for type CK20 alloy.

7


8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to two to three times the electrode wire diameter. All slag is removed between passes with a hammer and/or a stainless steel wire brush, or a needle gun using stainless steel needles. No peening is done on most welds, but light peening of each pass is sometimes helpful in producing sound welds. If a defect penetrates through the casting,

or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. 10


11


12

Post-Weld Heat Treatment To restore maximum corrosion resistance to welded type CK20 castings, they are heated to 2000°F (1093°C) minimum, held until uniformly at temperature, and then rapidly cooled by quenching in water, oil or air. Small welds which have been made to improve the appearance of casting surfaces that will not be subjected to corrosive attack in service may not require postweld heat treatment.

13


14



2.


3.



Procedure followed by experienced producers of high alloy castings in welding of type CK20 alloy as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy type CK20 (23-27 Cr, 19-22 Ni, 0.20 max. C) static and centrifugal castings.

2


Bare wire is preferred in this process.

Small defects and root passes are sometimes welded by fusion of the base metal only, without the addition of any filler metal. 3


4


5

Base Metal Preparation for Fabrication This process is seldom used for fabrication of composite castings. It is sometimes used for the root pass with subsequent passes laid down by some other process. More frequently, it is used for combining wrought and cast components. Parts to be joined are ground or machined to provide a groove when placed together. A good fit of the mating parts is essential for production of good welds. Good practice is to machine dry with no lubricant and to clean the parts thoroughly before assembly.

6

Preheat Temperature No preheat is required for type CK20 alloy.

7


8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Stringer bead placement is used. Beads are cleaned between passes with a stainless steel wire brush if required because of slag formation. No peening is done. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all

directions. 10


11


12

Post-Weld Heat Treatment To restore maximum corrosion resistance to welded type CK20 castings, they are heated to 2000°F (1093°C) minimum, held until uniformly at temperature, and then rapidly cooled by quenching in water, oil or air. Small welds which have been made to improve the appearance of casting surfaces that will not be subjected to corrosive attack in service may not require postweld heat treatment.

13


14



2.


3.



Procedure followed by experienced producers of high alloy castings in welding of type CN7M alloy as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy type CN7M (19-22 Cr, 27.5-30.5 Ni, 2-3 Mo, 3-4 Cu, 0.07 max. C) static and centrifugal castings.

2


Lime-coated electrode is preferred for DC welding. (This rod should not be used for AC.) Titania-coated electrode is used for AC welding and may be used for DC.

3


4


5


6

Preheat Temperature Normally, this alloy is not preheated; however, if the extent of the weld is substantial, the alloy may be preheated to 400-600°F (204-315°C).

7


8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to four times the electrode wire diameter. Interpass temperature is kept as low as possible. All slag is removed with chisel, hammer, and/or stainless steel wire brush.

Beads are lightly peened at edges first, then at center. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. If preheating is done, tack welding should be performed after the casting has been preheated in order to minimize the possibility of initiating a crack at the tack weld. 10

Electrical Characteristics Welding normally is done using DC reverse polarity. Successful welds can be made, however, using AC. Electrode sizes from 3/32 to 3/16 inch may be used with the current and voltage on the low side of the range suggested by the electrode manufacturer's specifications for the particular size rod. Due to the high electrical resistance of stainless steel, the burn-off rate of the electrode is much higher than for carbon steel. Arc length should be maintained as short as possible. A short arc length is very important when starting a weld pass since a long arc can sometimes be caused by initial hand recoil and may result in weld spatter or porosity.

11


12

Post-Weld Heat Treatment To restore maximum corrosion resistance to welded type CN7M castings, they are heated to 2050°F (1121°C) minimum, held until uniformly at temperature, and then rapidly cooled by quenching in water, oil or air. Small welds which have been made to improve the appearance of casting surfaces that will not be subjected to corrosive attack in service may not require postweld heat treatment.

13


14



2.


3.




Subject/Procedure

1


2

Filler Metal AWS ER-320

Bare wire is used in this process.

3


4

Base Metal Preparation for Repair This process is not being used for repair welding of castings.

5


6


7


8

Cavity Dimensions Good fitting, well prepared joints are essential, but dimensions are not critical.

9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Special attention is paid to directing the arc into the side walls and root of the joint. No peening is done. Beads are cleaned between passes with a stainless steel wire brush.

10

Electrical Characteristics Welding is done using DC reverse polarity. Wire diameter range is from 0.035 to 0.094 inch. For root passes, the smaller size wires are used. Currents and voltages suggested by the manufacturer's specifications for the wire size used are normally followed. Shielding gas is usually argon plus two percent (2%) oxygen at a flow rate of 30 to 50 cfh.

11

Technique for Welding Machined Castings This process is not being used to weld machined castings.

12

Post-Weld Heat TreatmentTo restore maximum corrosion resistance to welded type CN7M castings, they are heated to 2050°F (1121°C) minimum, held until uniformly at temperature, and then rapidly cooled by quenching in water, oil or air. Small welds which have been made to improve the appearance of casting surfaces that will not be subjected to corrosive attack in service may not require postweld heat treatment.

13


14


Make sure that surfaces to be welded are thoroughly cleaned (5 and 9).

2.


3.




Subject/Procedure

1


2


Bare wire is used in this process.

Small defects and root passes sometimes are welded by fusion of the base metal only, without the addition of any filler metal. 3


4

Base Metal Preparation for Repair Defects are removed before attempting any repair. Defect removal is accomplished by arc-air, chipping, gouging, grinding, sandblast, or machining, or by some combination of these operations. Defect removal to sound base metal is assured by the use of one or more of the following inspection processes: Visual, dye penetrant, or radiography.

5

Base Metal Preparation for Fabrication This process is not being used for fabrication of castings.

6

Preheat Temperature No preheat is required for type CN7M alloy.

7


8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited. Beads are cleaned with a stainless steel wire brush. No peening is done.

10


11


12

Post-Weld Heat Treatment To restore maximum corrosion resistance to welded type CN7M castings, they are heated to 2050°F (1121°C) minimum, held until uniformly at temperature, and then rapidly cooled by quenching in water, oil or air. Small welds which have been made to improve the appearance of casting surfaces that will not be subjected to corrosive attack in service may not require postweld heat treatment.

13


14



2.


3.



Procedure followed by experienced producers of high alloy castings in welding of type CW12M alloy as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy type CW12M (15.5-20 Cr, 16-20 Mo, 7.5 max. Fe, 5.25 max. W, 2.5 max. Co, 0.12 max. C, balance Ni) static and centrifugal castings.

2

Filler Metal AWS ENiCrMo-4-15 AWS ENiCrMo-5-15

Lime coated electrode is used.

3


4

Base Metal Preparation for Repair Defects are removed before attempting any repair. Defect removal is accomplished by arc-air, grinding, or machining, or by some combination of these operations. Defect removal to sound base metal is assured by the use of one or more of the following inspection processes: Visual, dye penetrant, or radiography. Where dye penetrant or radiographic inspection of a prepared cavity discloses shrinkage of a severity not in excess of that specified for the casting as a whole, acceptable practice is to weld such areas without further preparation (3.2.1).

5

Base Metal Preparation for Fabrication Parts to be fabricated by welding are shaped to provide a groove when placed together. The mating areas are either cast to shape and then ground, or ground or machined so that a good fit of the welding groove can be obtained. It is considered good practice to machine dry with no lubricant. Components are thoroughly cleaned before assembly.

6


7


8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to two and one-half times the electrode wire diameter. All slag is removed between passes with a hammer and/or stainless steel wire brush. Light peening of the first pass is sometimes helpful in producing a sound weld. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is

formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends to a minimum of 3/16 inch beyond the edge of the cavity in all directions. 10


11

Technique for Welding Machined Castings No special technique (9) is necessary for welding machined castings; it is good practice, however, to use small rods and low heat to avoid distortion. If the welded area will be subject to corrosion, it is desirable to quench the weld zone with a wet cloth between each pass. For small welds on heavy sections this may not be necessary since the heavy mass will tend to cool the weld zone rapidly.

12

Post-Weld Heat Treatment To restore maximum corrosion resistance to welded type CW12M castings, they are heated to 2150oF (1177oC) minimum, held for two hours or until uniformly at temperature, and then rapidly cooled by quenching in water, oil or air. Small welds which have been made to improve the appearance of casting surfaces that will not be subjected to corrosive attack in service may not require post weld heat treatment

13


14

Summary In order to produce welds that will satisfy the user's requirements, take the following precautions: 1.


2.


3.



Procedure followed by experienced producers of high alloy castings in welding of type CW12M alloy as reported in a survey of SFSA members

Section

Subject/Procedure

1

Base Metal Alloy type CW12M (15.5-20 Cr, 16-20 Mo, 7.5 max. Fe, 5.25 max. W, 2.5 max. Co, 0.12 max. C, balance Ni) static and centrifugal castings.

2

Filler Metal AWS ENiCrMo-4 Bare wire is used. AWS EniCrMo-5 AWS EniCrMo-7 Small defects and root passes are sometimes welded by fusion of the base metal only, without the addition of any filler metal.

3


4

Base Metal Preparation for Repair Defects are removed before attempting any repair. Defect removal is accomplished by arc-air, grinding, or machining, or by some combination of these operations. Defect removal to sound base metal is assured by the use of one or more of the following inspection processes: Visual, dye penetrant, or radiography. Where dye penetrant or radiographic inspection of a prepared cavity discloses shrinkage of a severity not in excess of that specified for the casting as a whole, acceptable practice is to weld such areas without further preparation (3.2.1).

5

Base Metal Preparation for Fabrication This process is not being used for the fabrication of castings.

6

Preheat Temperature No preheat is required for type CW12M alloy.

7


8

Cavity Dimensions The process is used mainly for surface welds, hence very little metal excavation is necessary and dimensions are not critical.

9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Beads are cleaned with hammer and/or stainless steel wire brush if any slag is present. No peening is done.

10

Electrical Characteristics Welding normally is done using DC reverse polarity. A non-consumable electrode made of thoriated tungsten (EWTh-2) is used. A high frequency method of starting the arc is preferred over a “scratch start” to avoid tungsten contamination of the weld. The arc should not be struck on a carbon block. Amperage and voltage suggested by the electrode manufacturer's specifications for the electrode size used are normally followed. Where filler metal is used, wire sizes range from 1/16 to 3/16 inch. Either helium or argon may be used for the inert shielding gas, but argon is preferred with a flow of 20 to 50 cfh.

11

Technique for Welding Machined Castings No special technique (9) is necessary for welding machined castings; it is good practice, however, to use small rods and low heat to avoid distortion. If the welded area will be subject to corrosion, it is desirable to quench the weld zone with a wet cloth between each pass. For small welds on heavy sections this may not be necessary since the heavy mass will tend to cool the weld zone rapidly.

12

Post-Weld Heat Treatment To restore maximum corrosion resistance to welded type CW12M castings, they are heated to 2150oF (1177oC) minimum, held for two hours or until uniformly at temperature, and then rapidly cooled by quenching in water, oil or air. Small welds which have been made to improve the appearance of casting surfaces that will not be subjected to corrosive attack in service may not require post weld heat treatment

13


14

Summary In order to produce welds that will satisfy the user's requirements, take the following precautions: 1.


2.


3.



Procedure followed by experienced producers of high alloy castings in welding of type CY40 alloy as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy type CY40 (14-17 Cr, 11 max. Fe, balance Ni, 0.40 max. C) static and centrifugal castings.

2

Filler Metal AWS ENiCrFe-1

Coated electrodes of the types listed are used for DC welding.

3


4


5


6


7


8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to two and one-half times the electrode wire diameter. All slag is removed between passes with a hammer and/or stainless steel wire brush. No peening is done. If the casting will be exposed to high temperature in service, remove all traces of slag from the finished weld area. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after

welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. 10


11


12

Post-Weld Heat Treatment Welded type CY40 castings are heated to 1900°F (1038°C) minimum, held until uniformly at temperature, and then rapidly cooled by quenching in water, oil or air. Small welds may not require postweld heat treatment.

13


14



2.


3.



Procedure followed by experienced producers of high alloy castings in welding of type CY40 alloy as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy type CY40 (14-17 Cr, 11 max. Fe, balance Ni, 0.40 max. C) static and centrifugal castings.

2

Filler Metal AWS ERNiCrFe-5

Bare wire is used.



4

Base Metal Preparation for Repair Defects are removed before attempting any repair. Defect removal is accomplished by sandblasting and grinding, or by some combination of these operations. Defect removal to sound base metal is assured by the use of one or more of the following inspection processes: Visual, dye penetrant, or radiography.

5


6

Preheat Temperature No preheat is required for type CY40 alloy.

7


8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Beads are cleaned with hammer and/or stainless steel wire brush if any slag is present. No peening is done.

10


11


12

Post-Weld Heat Treatment Welded type CY40 castings are heated to 1900°F (1038°C) minimum, held until uniformly at temperature, and then rapidly cooled by quenching in water, oil or air. Small welds may not require postweld heat treatment.

13


14



2.


3.



Procedure followed by experienced producers of high alloy castings in welding of type CZ100 alloy as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy type CZ100 (95 min. Ni, 3 max. Fe, 1.00 max. C) static and centrifugal castings.

2

Filler Metal AWS ENi-1

A coated electrode with 0.10 max. carbon.

3


4

Base Metal Preparation for Repair Defects are removed before attempting any repair. Defect removal is accomplished by arc-air, chipping, gouging, grinding, or machining, or by some combination of these operations. Defect removal to sound base metal is assured by the use of one or more of the following inspection processes: Visual, dye penetrant, or radiography.

5


6

Preheat Temperature No preheat is required for type CZ100 alloy. For complicated castings where high stresses may be developed in welding, preheat of 200-300°F (93-149°C) sometimes is desirable.

7

Section Size Section size usually is considered unimportant in welding this alloy. If sections are under ½ inch in thickness, however, use small electrodes and keep the heat low.

8

Cavity Dimensions Cavity dimensions are not critical. A minimum included angle of 80° should be maintained between the sides of the cavity, and a root radius of 3/16 to 1/4 inch should be provided to allow full access to the root.

9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to three times the electrode wire diameter. When breaking the arc, it should be shortened and the rate of travel increased to avoid crater oxidation. All slag is removed between passes and from the completed weld with a hammer and/or stainless steel wire brush, or a needle gun using stainless steel needles. Light peening of the first pass is helpful, but no peening is done on later passes. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of

3/16 inch beyond the edge of the cavity in all directions. Tack welding should be performed after the casting has been preheated in order to minimize the possibility of initiating a crack at the tack weld. 10

Electrical Characteristics Welding normally is done using DC reverse polarity. Successful welds can be made, however, using AC. Electrode sizes from 1/8 or 5/32 inch may be used with the current and voltage suggested by the electrode manufacturer's specifications for the particular size rod. Arc length should be maintained as short as possible. A short arc length is very important when starting a weld pass since a long arc can sometimes be caused by initial hand recoil and may result in weld spatter or porosity.

11


12

Post-Weld Heat Treatment No postweld heat treatment is given to welded type CZ100 alloy.

13


14



2.


3.



Procedure followed by experienced producers of high alloy castings in welding of type N-12M alloy as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy type N-12M (26-33 Mo, 6 max. Fe, balance Ni, 0.12 max. C) static and centrifugal castings.

2

Filler Metal AWS ENiMo-1-15

Lime coated electrode is used.

3


4


5

Base Metal Preparation for Fabrication Parts to be fabricated by welding are shaped to provide a groove when placed together. The mating areas are either cast to shape and then ground, or ground or machined so that a good fit of the welding groove can be obtained. Good practice is to machine dry with no lubricant. Components are thoroughly cleaned before assembly. Cleanliness is especially important in welding this alloy. Minimum weld restraint is arranged.

6

Preheat Temperature Normally this alloy is not preheated: however, if section size is over 3/4 inch in thickness, and the extent of the weld substantial, the alloy may be preheated to 800-1000°F (427538°C).

7

Section Size Section size usually is considered unimportant in welding this alloy (6).

8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to three times the electrode wire diameter. Stringer beads usually are preferred. All slag is removed between passes with a hammer and/or stainless steel wire brush. Light peening of the first pass is sometimes helpful in producing a sound weld. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it

extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. Tack welding should be performed after the casting has been preheated in order to minimize the possibility of initiating a crack at the tack weld. 10

Electrical Characteristics Welding normally is done using DC reverse polarity. Successful welds can be made, however, using AC. Electrode sizes from 1/8 to 5/32 inch may be used with the amperage and voltage suggested by the electrode manufacturer's specifications for the particular size rod. Due to the high electrical resistance of stainless steel, the burn-off rate of the electrode is much higher than for carbon steel. Arc length should be maintained as short as possible. A short arc length is very important when starting a weld pass since a long arc can sometimes be caused by initial hand recoil and may result in weld spatter or porosity.

11

Technique for Welding Machined Castings No special technique (9) is necessary for welding machined castings; it is good practice however, to use small rods and low heat to avoid distortion. If the welded area will be subject to corrosion, it is desirable to quench the weld zone with a wet cloth between each pass. For small welds on heavy sections this may not be necessary since the heavy mass will tend to cool the weld zone rapidly.

12

Post-Weld Heat Treatment To restore maximum corrosion resistance to welded type N-12M castings, they are heated to 2100oF (1149oC) minimum, held until uniformly at temperature, and then rapidly cooled by quenching in water, oil or air.

13


14



2.


3.



Procedure followed by experienced producers of high alloy castings in welding of type N-12M alloy as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy type N-12M (26-33Mo, 6 max. Fe, balance Ni, 0.12 max. C) static and centrifugal castings.

2

Filler Metal AWS ERNiMo-1 AWS ERNiMo-7

Bare wire is used.



4

Base Metal Preparation for Repair Defects are removed before attempting any repair. Defect removal is accomplished by arc-air, grinding, or machining, or by some combination of these operations. Defect removal to sound base metal is assured by the use of one or more of the following inspection processes: Visual, dye penetrant, or radiography.

5


6

Preheat Temperature No preheat is required for type N-12M alloy.

7


8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Stringer bead placement is used. No peening is done. Any slag or oxide present is removed by chipping or brushing with a stainless steel wire brush.

10

Electrical Characteristics Welding is done using DC straight polarity. A non-consumable electrode made of thoriated tungsten (EWTh-2) is used. A high frequency method of starting the arc is preferred over a "scratch start" to avoid tungsten contamination of the weld. The arc should not be struck on a carbon block. Amperages and voltages suggested by the manufacturer's specifications for the electrode size used are normally followed. Where filler metal is used, wire sizes range from 1/16 to 3/16 inch. Either helium or argon may be used for the inert shielding gas, but argon is preferred with a flow of 20 to 50 cfh.

11

Technique for Welding Machined Castings No special technique (9) is necessary for welding machined castings; however, it is good practice, however, to use small rods and low heat to avoid distortion. If the welded area will be subject to corrosion, it is desirable to quench the weld zone with a wet cloth between each pass. For small welds on heavy sections, this may not be necessary because the heavy mass will tend to cool the weld zone rapidly.

12

Post-Weld Heat Treatment To restore maximum corrosion resistance to welded type N-12M castings, they are heated to 2100oF (1149oC) minimum, held until uniformly at temperature, and then rapidly cooled by quenching in water, oil or air. Small welds that have been made to improve the appearance of casting surfaces that will not be subjected to corrosive attack in service, may not require postweld heat treatment.

13


14



2.


3.



Procedure followed by experienced producers of high alloy castings in welding of type M-35 alloy as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy type M-35 (26-33 Cu, 3.5 max. Fe, balance Ni, 0.35 max. C) static and centrifugal castings.

2

Filler Metal AWS ENiCu-7

Electrode is preferred for welding this alloy.

3


4


5


6

Preheat Temperature No preheat is required for type M-35 alloy. For complicated castings where high stresses may be developed in welding, preheat of 200-300°F (93-149°C) is sometimes desirable.

7

Section Size Section size usually is considered unimportant in welding this alloy. For sections under ½ inch in thickness, small electrodes and low current are used to keep temperature as low as possible.

8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to three times the electrode wire diameter. Stringer beads are preferred. All slag is removed between passes with a hammer and/or stainless steel wire brush. No peening is done. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. Tack welding should be performed after the casting has been preheated in

order to minimize the possibility of initiating a crack at the tack weld. 10


11


12

Post-Weld Heat Treatment No postweld heat treatment is used for type M-35 castings.

13


14



2.


3.


4.

Grind surface area around the groove or cavity to be welded to remove silica from molding sand to prevent surface cracking around weld-base metal interface.


Procedure followed by experienced producers of high alloy castings in welding of type M-35 alloy as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy type M-35 (26-33 Cu, 3.5 max. Fe, balance Ni, 0.35 max. C) static and centrifugal castings.

2

Filler Metal AWS ERNiCu-1 AWS ERNiCu-7

Bare wire is used.



4

Base Metal Preparation for Repair Defects are removed before attempting any repair. Defect removal is accomplished by arc-air, grinding, or machining, or by some combination of these operations. Defect removal to sound base metal is assured by the use of one or more of the following inspection processes: Visual, dye penetrant, or radiography.

5


6

Preheat Temperature No preheat is required for type M-35 alloy.

7


8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Agitation of the molten puddle is avoided, and the puddle plus the hot end of filler metal wire is kept within the shielding gas at all times. Care is taken to prevent air contamination of the shielding gas from drafts.

10

Electrical Characteristics Welding is done using DC straight polarity. A non-consumable electrode made of thoriated tungsten (EWTh-2) is used. A high frequency method of starting the arc is preferred over a "scratch start" to avoid tungsten contamination of the weld. The arc should not be struck on a carbon block. Currents and voltages suggested by the manufacturer's specifications

for the electrode size used are normally followed. Where filler metal is used, wire sizes range from 1/16 to 1/8 inch. Either helium or argon may be used for the inert shielding gas, but argon is preferred with a flow of 20 to 50 cfh. 11


12

Post-Weld Heat Treatment No postweld heat treatment is used for type M-35 castings.

13


14



2.


3.


4.

Grind surface area around the groove or cavity to be welded to remove silica from molding sand to prevent surface cracking around weld-base metal interface.


Procedure followed by experienced producers of high alloy castings in welding of type HC alloy as reported in a survey of SFSA members Section 1

Subject/Procedure Base Metal Alloy type HC (26-30Cr, 4max. Ni, 0.50max.C) static and centrifugal castings. NOTE: This alloy is considered extremely difficult to weld because of low ductility and tendency toward cleavage type fractures. Several re-welds may be required.

2

Filler Metal AWS E446-15 Lime coated electrodes are preferred for welding type HC castings. AWS E310-15 AWS E312-15 AWS E329-15

Lime coated electrodes are also used where improved ductility of the weld is required.

3


4

Base Metal Preparation for Repair Defects are removed before attempting any repair. Defect removal is accomplished by arc-air, chipping, gouging, grinding or machining, or by some combination of these operations. Defect removal to sound base metal is assured by the use of one or more of the following inspection processes: Visual, dye penetrant, or radiography.

5


6

Preheat Temperature Preheat temperatures from 400-600°F (204-313°C) are used in welding this alloy.

7

Section Size Section size usually is considered important in welding this alloy. If section thickness is 1/4 inch or less, preheat is sometimes omitted but on heavier sections preheat is required. Although successful welds are made with low preheat temperatures, it may be necessary to go to the high end of the range to obtain good welds. When the depth of a defect exceeds 15 percent of the wall thickness, attempts to repair by welding are often considered to be useless.

8

Cavity Dimensions Cavity dimensions are not critical. A minimum included angle of 30° (included angles up to 90° sometimes are used) should be maintained between the sides of the cavity, and a root radius of 3/16 to 1/4 inch should be provided to allow full access to the root. (Refer to Secs. 6 and 7)

9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to three times the electrode wire diameter. Staggered stringer beads are used on heavy sections. All slag is removed between passes with a hammer and/or wire brush. Generally, peening is not done but a light peen after each pass is sometimes helpful. If parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. Tack welding should be performed after the casting has been preheated in order to minimize the possibility of initiating a crack at the tack weld.

10


11

Technique for Welding Machined Castings No special technique (see Sec. 9) is necessary for welding machined castings; it is good practice, however, to use small rods and low heat to avoid distortion.

12

Post-Weld Heat Treatment Welds are usually heated to the range 1550-1900°F (843-1038°C) and then cooled rapidly.

13

Non-Destructive Tests Welds are tested for quality by one or more of the following methods of inspection: Visual, dye penetrant, radiography or pressure.

14

Summary To produce welds that will satisfy the user's requirements, take the following precautions: 1. Make sure that all defects have been removed to sound base metal (4) and that surfaces to be welded are thoroughly cleaned (5 and 9). 2. Use the proper filler metal (2). 3. Use a welding technique (9) which will produce welds free of porosity, undercutting or lack of penetration.


Procedure followed by experienced producers of high alloy castings in welding of type HC alloy as reported in a survey of SFSA members Section 1

Subject/Procedure Base Metal Alloy type HC (26-30Cr, 4max. Ni, 0.50max.C) centrifugal castings. NOTE: This alloy is considered extremely difficult to weld because of low ductility and tendency toward cleavage type fractures.

2

Filler Metal This process is used mainly for root passes which are welded by fusion of the base metal without the addition of any filler metal. Subsequent passes are laid down by the shield metalarc process (SMAW).

3


4


5


6

Preheat Temperature Preheat temperatures from 400-600°F (204-313°C) are used in welding this alloy.

7

Section Size Section size usually is considered important in welding this alloy. (See procedure for shielded metal-arc welding of type HC alloy.)

8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. If parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. Tack welding should be performed after the casting has been preheated in order to minimize the possibility of initiating a crack at the

tack weld. 10

Electrical Characteristics Welding normally is done using DC straight polarity. A non-consumable electrode made of thoriated tungsten (EWTh-2) is used. A high frequency method of starting the arc is preferred over a "scratch start" to avoid tungsten contamination of the weld. The arc should not be struck on a carbon block. Currents and voltages suggested by the manufacturer's specifications for the electrode size used are normally followed. Either helium or argon may be used for the inert shielding gas, but argon is preferred with a flow of 15 to 25 cfh.

11

Technique for Welding Machined Castings No special technique (9) is necessary for welding machined castings.

12

Post-Weld Heat Treatment Welds are usually heated to the range 1550-1900°F (843-1038°C) and then cooled rapidly.

13


14

Summary In order to produce welds that will satisfy the user's requirements, it is customary to take the following precautions: 1. Make sure that all defects have been removed to sound base metal (4) and that surfaces to be welded are thoroughly cleaned (5 and 9). 2. Use a welding technique (9) which will produce welds free of porosity, undercutting or lack of penetration.


Procedure followed by experienced producers of high alloy castings in welding of type HF alloy as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy type HF (19-23Cr, 9-12Ni, 0.20-0.40C) static and centrifugal castings.

2

Filler Metal AWS E308-15 AWS E310-15 (0.30C) AWS E330-15 AWS E308-16 AWS E309-16

Lime coated electrodes are used for DC welding of this alloy. (These rods should not be used for AC) Titania coated electrodes are preferred for AC welding and may be used for DC.

3


4

Base Metal Preparation for Repair Defects are removed before attempting any repair. Defect removal is accomplished by arc-air, chipping, gouging, grinding or machining, or by some combination of these operations. Defect removal to sound base metal is assured by the use of one or more of the following inspection processes: Visual, dye penetrant, or radiography. Where dye penetrant or radiographic inspection of a prepared cavity discloses shrinkage of a severity not in excess of that specified for the casting as a whole, acceptable practice is to weld such areas without further preparation. (See Introduction, welding (3.2.1).

5


6

Preheat Temperature Normally this alloy is not preheated; however, if the section size is over 3/4 inch in thickness, and the extent of the weld substantial, the alloy may be preheated to 200-400°F (93-204°C). Prior solution annealing at 1800-2100°F (982-1149°C) is often used before welding of aged castings.

7

Section Size Section size usually is considered important in welding this alloy. Heavy sections may require preheat or postheat. (6 and 12)

8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to three times the electrode wire diameter. Sometimes stringer beads are used exclusively, or are used for root passes with weave beads use for later passes. No peening is done. All slag is removed between passes and from finished weld with hammer, grinder and/or wire brush. Residual slag is very corrosive to the alloy at high temperature. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. Tack welding should be performed after the casting has been preheated in order to minimize the possibility of initiating a crack at the tack weld.

10


11


12

Post-Weld Heat Treatment In general no post-weld heat treatment is given to type HF alloy, but when section size exceeds one inch castings may be stress relieved at 1600°F (871°C) after welding.

13


14




Subject/Procedure

1


2

Filler Metal AWS ER310 (0.30C)

Bare wire is used.

3

Position This process is being used mainly for fabrication of tubes positioned horizontally on rolls.

4

Base Metal Preparation for Repair This process is not being used for repair welding of castings.

5


6


7


8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Stringer beads are used on the root pass, then weave beads on subsequent filler passes. Beads are cleaned between passes by wire brushing. No peening is done.

10

Electrical Characteristics Welding is done using DC reverse polarity. Wire diameter range is from 0.035 to 0.062 inch. Currents and voltages suggested by the manufacturer's specifications for the wire size used are normally followed. Shielding gas is usually argon plus 2-5 percent oxygen at a flow rate of 30 to 50 cfh.

11


12

Post-Weld Heat Treatment Welded castings may be stress relieved by heat to 1600°F (871°C) and held for one hour.

13


14

Summary To produce welds that will satisfy the user's requirements, take the following precautions: 1. Make sure that surfaces to be welded are thoroughly cleaned (5 and 9). 2. Use the proper filler metal (2). 3. Use a welding technique (9) which will produce welds free of porosity, undercutting or lack of penetration.



Subject/Procedure

1


2

Filler Metal This process is used mainly for root passes which are welded by fusion of the base metal without the addition of any filler metal. Subsequent passes are laid down by the shield metal-arc process (SMAW).

3


4


5


6

Preheat Temperature No preheat is required for type HF alloy.

7


8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions.

10


11


12

Post-Weld Heat Treatment Usually no postweld heat treatment is required.

13


14

Summary To produce welds that will satisfy the user's requirements, take the following precautions: 1. Make sure that all defects have been removed to sound base metal (4) and that surfaces to be welded are thoroughly cleaned (5 and 9). 2. Use a welding technique (9) which will produce welds free of porosity, undercutting or lack of penetration.


Procedure followed by experienced producers of high alloy castings in welding of type HH alloy as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy type HH (24-28CR, 11-14Ni, 0.20-0.50C) static and centrifugal castings. Also types HE (26-30Cr, 8-11Ni, 0.20-0.50C) and HI (26-30Cr, 14-19Ni, 0.20-0.50C)

2

Filler Metal AWS E309-15HC Lime coated, high carbon electrode is preferred for DC welding. (Should not be used for AC) AWS E309-16HC Titania coated, high carbon electrode is used for AC welding and may be used for DC. AWS E312-15 or AWS E310-15HC are used for welding alloy types HE and HI.

3

Position All welding usually is done in the "flat" position. A ± 15° angle of the groove with the horizontal plane normally is considered flat (8).

4


5


6

Preheat Temperature Normally this alloy is not preheated; however, if the section size is over 3/4 inch in thickness, and the extent of the weld substantial, the alloy may be preheated to 200-400°F (93-204°C). Prior solution annealing at 1800-2100°F (982-1149°C) followed by furnace or air cooling is often used before welding of aged castings.

7

Section Size Section size usually is considered important in welding this alloy. When sections are under ½ inch in thickness, good practice is to use an electrode no larger than 1/8 inch diameter.

8

Cavity Dimensions Cavity dimensions are not critical. A minimum included angle of 30° (included angles up to 90° sometimes are used) should be maintained between the sides of the cavity, and a root radius of 3/16 to 1/4 inch should be provided to allow full access to the root. For large defects, a vertical uphill welding position is sometimes used.

9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to three times the electrode wire diameter. All slag is removed between passes and from finished weld with a hammer and/or stainless steel wire brush. Residual slag is very corrosive to the alloy at high temperature. No peening is done. Any undercuts or rough spots in beads are faired in by grinding before next pass. Interpass temperatures are held to 300°F (149°C). If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. Tack welding should be performed after the casting has been preheated in order to minimize the possibility of initiating a crack at the tack weld.

10


11

Technique for Welding Machined Castings No special technique (9) is necessary for welding machined castings; it is good practice, however, to use small rods and low heat to avoid distortion.

12

Post-Weld Heat Treatment Welded castings of alloy types HH, HE and HI usually are not given any post-weld heat treatment. In some cases where welds are large or located in critical areas of geometrically complicated castings, they are given a heat treatment of 3-4 hours at 19002050°F (1038-1121°C) and either furnace cooled or air cooled.

13


14




Subject/Procedure

1


2

Filler Metal AWS ER309 HH alloy.

Bare wire is used with composition modified to match carbon content of the

AWS ER310

Bare wire is used for types HE and HI.

3


4


5


6

Preheat Temperature Normally this alloy is not preheated; however, if the section size is over 3/4 inch in thickness, and the extent of the weld substantial, the alloy may be preheated to 200-400°F (93-204°C). Prior solution annealing at 1800-2100°F (982-1149°C) followed by air or furnace cooling is often used before welding of aged castings.

7


8

Cavity Dimensions Cavity dimensions are not critical. A minimum included angle of 30° (included angles up to 90° are sometimes used) should be maintained between the sides of the cavity, and a root radius of 3/16 to 1/4 inch should be provided to allow full access to the root.

9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to the diameter of the gas nozzle. Maximum bead thickness is held to 1/8 inch. All oxides are cleaned from beads by hammer and/or wire brush. No peening is done. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16

inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. 10

Electrical Characteristics Welding is done using DC reverse polarity. Wire diameter range is from 0.035 to 0.094 inch. Currents and voltages suggested by the manufacturer's specifications for the wire size used are normally followed. Shielding gas is usually argon plus two percent (2%) oxygen at a flow rate of 30 to 50 cfh. An alternate mixture of 75 percent argon plus 25 percent carbon dioxide at a flow rate of 20 cfh is also used but may affect that corrosion resistance of the weld adversely on multipass welds.

11


12

Post-Weld Heat Treatment Welded castings of alloy types HH, HE and HI usually are not given any post-weld heat treatment. In some cases where welds are large or located in critical areas of geometrically complicated castings, they are given a heat treatment of 3-4 hours at 19002050°F (1038-1121°C) and either air cooled or furnace cooled.

13


14




Subject/Procedure

1


2

Filler Metal This process is used mainly for root passes which are welded by fusion of the base metal without the addition of any filler metal. Subsequent passes are laid down by the shield metalarc process. (See procedure for that process.)

3


4


5


6

Preheat Temperature No preheat is required for type HH alloy.

7


8


9


10


11


12


13


14

Summary To produce welds that will satisfy the user's requirements, take the following precautions: 1. Make sure that all defects have been removed to sound base metal (4) and that surfaces to be welded are thoroughly cleaned (5 and 9). 2. Use a welding technique (9) which will produce welds free of porosity, undercutting or lack of penetration.


Procedure followed by experienced producers of high alloy castings in welding of type HK alloy as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy type HK (24-28CR, 18-22Ni, 0.20-0.60C) static and centrifugal castings. Also types HL (28-32Cr, 18-22Ni, 0.20-0.60C),HN (19-23Cr, 23-27Ni, 0.20-0.50C) and HP

2

Filler Metal AWS E310-15HC Lime coated, high carbon electrode is preferred for DC welding. (Should not be used for AC) AWS E310-16HC Titania coated, high carbon electrode is used for AC welding and may be used for DC. AWS E330-15HC Lime coated electrode is used for welding alloy type HN. The carbon content of the electrode used is matched to that of the base metal as closely as possible. HP

3

Position All welding usually is done in the "flat" position. A ± 15° angle of the groove with the horizontal plane normally is considered flat (8).

4


5


6

Preheat Temperature Normally this alloy is not preheated; however, if the section size is over 3/4 inch in thickness, and the extent of the weld substantial, the alloy may be preheated to 200-400°F (93-204°C). Prior solution annealing at 1800-2100°F (982-1149°C) followed by furnace or air cooling is often used before welding of aged castings.

7

Section Size Section size usually is considered important in welding this alloy. Changes in welding technique sometimes are made when section thickness exceeds one inch (8 and 9).

8

Cavity Dimensions Cavity dimensions are not critical. A minimum included angle of 30° (included angles up to

90° sometimes are used) should be maintained between the sides of the cavity, and a root radius of 3/16 to 1/4 inch should be provided to allow full access to the root. For large defects, castings may be preheated (6) and a vertical uphill welding position is sometimes used. 9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to three times the electrode wire diameter. On heavy sections, the sides of the cavity or groove are "buttered" with stringer beads before the central portion of the weld is completed. Very little peening is done. All slag is removed between passes and from finished weld with a hammer and/or stainless steel wire brush. Residual slag is very corrosive to the alloy at high temperature. Any undercuts or rough spots in beads are faired in by grinding before next pass. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. Tack welding should be performed after the casting has been preheated in order to minimize the possibility of initiating a crack at the tack weld.

10


11


12

Post-Weld Heat Treatment Welded castings of alloy types HK usually are not given any post-weld heat treatment. For large welds and heavy sections it is sometimes desirable to give a stress relief treatment of one hour at 1600°F (871°C) minimum and either air cool or furnace cool.

13


14




Subject/Procedure

1

Base Metal Alloy type HK (24-28CR, 18-22Ni, 0.20-0.60C) static and centrifugal castings. Also types HL (28-32Cr, 18-22Ni, 0.20-0.60C), HN (19-23Cr, 23-27Ni, 0.20-0.50C), and HP

2

Filler Metal AWS ER310HC Bare wire with carbon content matched to that of the base metal as closely as possible. AWS ER330HC Bare wire is used for welding type HN. HP

3


4

Base Metal Preparation for Repair This process is not being used for repair of casting defects.

5


6

Preheat Temperature Normally this alloy is not preheated; however, if the section size is over 3/4 inch in thickness, and the extent of the weld substantial, the alloy may be preheated to 200-400°F (93-204°C). Prior solution annealing at 1800-2100°F (982-1149°C) followed by air or furnace cooling is often used before welding of aged castings.

7


8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to filler passes after stringer bead root pass. Beads are carefully cleaned between passes with a stainless steel wire brush. No peening is done.

10

Electrical Characteristics

Welding is done using DC reverse polarity. Wire diameter range is from 0.035 to 0.062 inch. Currents and voltages suggested by the manufacturer's specifications for the wire size used are normally followed. Shielding gas is usually argon plus two percent (2%) oxygen at a flow rate of 30 to 50 cfh. 11


12

Post-Weld Heat Treatment Welded castings of type HK alloy usually are not given any post-weld heat treatment. For large welds and heavy sections it is sometimes desirable to give a stress relief treatment of one hour at 1600°F (871°C) minimum.

13


14




Subject/Procedure

1

Base Metal Alloy type HK (24-28CR, 18-22Ni, 0.20-0.60C) static and centrifugal castings. Also types HL (28-32Cr, 18-22Ni, 0.20-0.60C), HN (19-23Cr, 23-27Ni, 0.20-0.50C), and HP

2

Filler Metal AWS ER310HC Bare wire is used for filler passes on multipass welds. Root passes are usually made by fusion of the base metal without the addition of any filler metal. Subsequent passes are laid down by this or by the shielded metal-arc process (SMAW). Carbon content of wire is matched to that of the base metal. AWS ER330HC Bare wire is used for welding type HN. HP

3


4

Base Metal Preparation for Repair Defects are removed before attempting any repair. Defect removal is accomplished by arc-air, chipping, gouging, grinding or machining, or by some combination of these operations. Defect removal to sound base metal is assured by the use of one or more of the following inspection processes: Visual, dye penetrant, or radiography. Where dye penetrant or radiographic inspection of a prepared cavity discloses shrinkage of a severity not in excess of that specified for the casting as a whole, acceptable practice is to weld such areas without further preparation(3.2.1).

5


6

Preheat Temperature No preheat is required for type HK alloy.

7


8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or

weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to 3/8 inch. No peening is done. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. 10

Electrical Characteristics Welding is done using DC straight polarity. A non-consumable electrode made of thoriated tungsten (EWTh-2) is used. A high frequency method of starting the arc is preferred over a "scratch start" to avoid tungsten contamination of the weld. The arc should not be struck on a carbon block. Currents and voltages suggested by the manufacturer's specifications for the electrode size used are normally followed. Where filler metal is used, wire size is 1/16 inch. Either helium or argon may be used for the inert shielding gas, but argon is preferred with a flow of 20 to 50 cfh.

11

Technique for Welding Machined Castings No special technique (9) is necessary for welding machined castings; however, use low heat to avoid distortion.

12


13


14



Procedure followed by experienced producers of high alloy castings in welding of type HT alloy as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy type HT (15-19CR, 33-37Ni, 0.35-0.75C) static and centrifugal castings.

2

Filler Metal AWS E330-15 Lime coated electrodes is modified to deposit weld metal with carbon content approximately matching the composition of the base metal are preferred.

3

Position Whenever possible, all welding is done in the "flat" position. A ± 15° angle of the groove with the horizontal plane normally is considered flat. (8)

4


5


6

Preheat Temperature Normally this alloy is not preheated; however, if the section size is over 3/4 inch in thickness, and the extent of the weld substantial, the alloy may be preheated to 200-400°F (93-204°C). Prior solution annealing at 1800-2100°F (982-1149°C) followed by furnace cooling is often used before welding of aged castings.

7

Section Size Section size usually is considered important in welding this alloy. When sections are under ½ inch in thickness, good practice is to use an electrode no larger than 1/8 inch diameter. For sections thicker than 3/4 inch, preheat may be helpful (6).

8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is

limited to three times the electrode wire diameter. Sides of the cavities are sometimes "buttered" to minimize dilution of weld deposit by base metal. Any undercuts or rough spots in beads are faired in by grinding before next pass. No peening is done. All slag is removed between passes and from finished weld with a hammer and/or stainless steel wire brush. Residual slag is very corrosive to the alloy at high temperature. Interpass temperatures are held to 300°F (149°C). Inspection of weld quality during course of work is desirable (13). If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. Tack welding should be performed after the casting has been preheated in order to minimize the possibility of initiating a crack at the tack weld. 10


11

Technique for Welding Machined Castings No special technique (9) is necessary for welding machined castings; however, use small rods and low heat to avoid distortion. Weld beads are peened to counteract contraction.

12

Post-Weld Heat Treatment Welded castings of alloy types HT usually are not given any post-weld heat treatment. In some cases where welds are large or located in critical areas of geometrically complicated castings, they are heat treated for 3-4 hours at 1900-2100°F (1038-1149°C) and furnace cooled.

13


14




Subject/Procedure

1


2

Filler Metal AWS ER330 Bare wire with composition modified to deposit weld metal approximately matching the carbon content of the base metal.

3


4


5


6


7

Section Size Section size usually is considered unimportant in welding this alloy. In welding sections over ½ inch thick the type of weld bead is changed (9).

8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to sections thicker than ½ inch. Parts to be welded are carefully tacked to maintain good fit and matching of groove lands.

10

Electrical Characteristics Welding is done using DC reverse polarity. Wire diameter range is from 0.035 to 1/16 inch. Currents and voltages suggested by the manufacturer's specifications for the wire size used are normally followed. Shielding gas is usually 100 percent argon at a flow rate of 30 to 35 cfh.

11

Technique for Welding Machined Castings This process is not being used for welding of machined castings.

12

Post-Weld Heat Treatment Welded castings of type HT alloy usually are not given any post-weld heat treatment. In some cases where welds are large or located in critical areas of geometrically complicated castings, they are heat treated for 3-4 hours at 1900-2100°F (1038-1149°C) and furnace cooled.

13


14




Subject/Procedure

1


2

Filler Metal This process is used mainly for root passes which are welded by fusion of the base metal without the addition of any filler metal. Subsequent passes are laid down by the shielded metal-arc process (SMAW).

3


4


5


6

Preheat Temperature No preheat is required for type HT alloy.

7


8


9


10

Electrical Characteristics Welding is done using DC straight polarity. A non-consumable electrode made of thoriated tungsten (EWTh-2) is used. A high frequency method of starting the arc is preferred over a "scratch start" to avoid tungsten contamination of the weld. The arc should not be struck on a carbon block. Currents and voltages suggested by the manufacturer's specifications for the electrode size used are normally followed. Either helium or argon may be used for the inert shielding gas, but argon is preferred with a flow of 20 to 50 cfh.

11


12


13


14



Procedure followed by experienced producers of high alloy castings in welding of type HU alloy as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy type HU (17-21CR, 37-41Ni, 0.35-0.75C) static and centrifugal castings.

2

Filler Metal AWS E330-15 Lime coated electrodes modified to deposit weld metal with carbon content approximately matching the composition of the base metal.

3

Position All welding is done in the "flat" position. A ± 15° angle of the groove with the horizontal plane normally is considered flat (8).

4


5


6

Preheat Temperature Normally this alloy is not preheated; however, if the section size is over 3/4 inch in thickness, and the extent of the weld substantial, the alloy may be preheated to 200-400°F (93-204°C). Prior solution annealing at 1800-2100°F (982-1149°C) is often used before welding.

7

Section Size Section size usually is considered important in welding this alloy. When sections are under ½ inch in thickness, good practice is to use an electrode no larger than 1/8 inch diameter. For sections thicker than 3/4 inch, preheat may be helpful (6).

8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to three times the electrode wire diameter. Sides of the cavities are sometimes "buttered" to

minimize dilution of weld deposit by base metal. Any undercuts or rough spots in beads are faired in by grinding before next pass. No peening is done. All slag is removed between passes and from finished weld with a hammer, stainless steel wire brush, or needle gun using stainless steel needles. Residual slag may be corrosive to the alloy at high temperature. Interpass temperatures are held to 300°F (149°C). Inspection of weld quality during course of work is desirable (13). If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. Tack welding should be performed after the casting has been preheated in order to minimize the possibility of initiating a crack at the tack weld. 10


11

Technique for Welding Machined Castings No special technique (9) is necessary for welding machined castings; however, use small rods and low heat to avoid distortion. Weld beads are peened to counteract contraction.

12

Post-Weld Heat Treatment Welded castings of alloy types HU usually are not given any post-weld heat treatment. In some cases where welds are large or located in critical areas of geometrically complicated castings, they are heat treated for 3-4 hours at 1900-2050°F (1038-1121°C) and furnace cooled.

13


14




Subject/Procedure

1


2

Filler Metal AWS ER330 Bare wire with composition modified to deposit weld material approximately matching the carbon content of the base metal.

3


4


5


6

Preheat Temperature Normally this alloy is not preheated; however, if the section size is over 3/4 inch in thickness, and the extent of the weld substantial, the alloy may be preheated to 200-400°F (93-204°C). Prior solution annealing at 1800-2100°F (982-1149°C) followed by furnace cooling is often used before welding.

7

Section Size Section size usually is considered unimportant in welding this alloy. In welding sections over ½ inch thick the type of weld bead is changed (9).

8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to sections thicker than ½ inch. Parts to be welded are carefully tacked to maintain good fit and matching of groove lands.

10

Electrical Characteristics Welding is done using DC reverse polarity. Wire diameter range is from 0.035 to 0.063 inch. Currents and voltages suggested by the manufacturer's specifications for the wire size used are normally followed. Shielding gas is usually argon plus two percent (2%) oxygen at a flow rate of 30 to 50 cfh.

11

Technique for Welding Machined Castings This process is not being used for welding of machined castings.

12

Post-Weld Heat Treatment Welded castings of type HU alloy usually are not given any post-weld heat treatment. In some cases where welds are large or located in critical areas of geometrically complicated castings, they are heat treated for 3-4 hours at 1900-2050°F (1038-1121°C) and furnace cooled.

13


14




Subject/Procedure

1


2

Filler Metal This process is used mainly for root passes which are welded by fusion of the base metal without the addition of any filler metal. Subsequent passes are laid down by the shielded metal-arc or gas metal-arc processes. (See procedure for those processes.) When gas tungsten-arc process is used for entire weld AWS ER330(high carbon), bare wire is used for filler metal.

3


4


5


6

Preheat Temperature No preheat is required for type HU alloy.

7


8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all

directions. 10


11


12

Post-Weld Heat Treatment Welded castings of type HU alloy usually are not given any post-weld heat treatment.

13


14



Procedure followed by experienced producers of high alloy castings in welding of type HW alloy as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy type HW (10-14CR, 58-62Ni, 0.35-0.75C) static and centrifugal castings.

2

Filler Metal AWS ENiCr-1 and AWS EniCrFe-1 Lime coated electrodes are preferred. AWS E330-15 Lime coated electrode is also used.

3

Position Welding is usually done in the "flat" position. A ± 15° angle of the groove with the horizontal plane normally is considered flat. Successful welds can be made in all positions.

4


5


6

Preheat Temperature Normally this alloy is not preheated; however, if the section size is over 3/4 inch in thickness, and the extent of the weld substantial, the alloy may be preheated to 200-400°F (93-204°C). Prior solution annealing at 1800-2100°F (982-1149°C) followed by furnace cooling is often used before welding.

7

Section Size Section size usually is considered important in welding this alloy.

8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to three times the electrode wire diameter. All slag is removed between passes and from finished weld with a hammer and/or stainless steel wire brush. Light peening of each pass before laying down next pass is sometimes helpful. If a defect penetrates through the casting,

or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. 10


11


12

Post-Weld Heat Treatment Welded castings of alloy types HW usually are not given any post-weld heat treatment. In some cases where welds are large or located in critical areas of the casting, they are given a stress relief treatment of heating to 1750°F (955°C) for two hours.

13


14



Procedure followed by experienced producers of high alloy castings in welding of type HX alloy as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy type HX (15-19CR, 64-68Ni, 0.35-0.75C) static and centrifugal castings.

2

Filler Metal AWS ENiCrFe-1 Lime coated electrode is preferred. AWS e330-15HC Lime coated electrode is also used.

3

Position Welding usually is done in the "flat" position. A ± 15° angle of the groove with the horizontal plane normally is considered flat.

4


5


6

Preheat Temperature Normally this alloy is not preheated; however, if the section size is over 3/4 inch in thickness, and the extent of the weld substantial, the alloy may be preheated to 200-400°F (93-204°C). Prior solution annealing at 1800-2100°F (982-1149°C) followed by furnace cooling is often used before welding of aged castings.

7

Section Size Section size usually is considered important in welding this alloy.

8


9

Welding Technique Surfaces to be welded should be dry and cleaned to remove any residue from cavity or weld groove preparation or other previous operations. Lack of attention to this may result in defective welds. Either stringer or weave bead placement is used. Weaving, if any, is limited to three times the electrode wire diameter. All slag is removed between passes and from finished weld with a hammer and/or stainless steel wire brush. Residual slag may be corrosive to the alloy at high temperature. Interpass temperatures held to 200°F (93°C)

maximum is sometimes helpful. Light peening of each pass before laying down next pass is sometimes desirable. If a defect penetrates through the casting, or if parts to be fabricated fit together poorly, a 3/16 inch backing plate is formed to the inside contour of the casting and tack welded in place. The backing plate, which should be removed after welding, is generally of such a size that it extends a minimum of 3/16 inch beyond the edge of the cavity in all directions. 10


11


12

Post-Weld Heat Treatment Welded castings of alloy types HX usually are not given any post-weld heat treatment.

13


14



Procedure followed by experienced producers of high alloy castings in welding of type HX alloy as reported in a survey of SFSA members Section

Subject/Procedure

1

Base Metal Alloy type HX (15-19CR, 64-68Ni, 0.35-0.75C) static and centrifugal castings.

2

Filler Metal This process is used mainly for root passes which are welded by fusion of the base metal without the addition of any filler metal. Subsequent passes are laid down by the shielded metal-arc process (SMAW).

3


4


5


6

Preheat Temperature No preheat is required for type HX alloy.

7


8


9


10

Electrical Characteristics Welding is done using DC straight polarity. A non-consumable electrode made of thoriated tungsten (EWTh-2) is used. A high frequency method of starting the arc is preferred over a "scratch start" to avoid tungsten contamination of the weld. The arc should not be struck on a carbon block. Currents and voltages suggested by the manufacturer's specifications for the electrode size used are normally followed. Either helium or argon may be used for the inert shielding gas, but argon is preferred with a flow of 20 to 50 cfh.

11


12

Post-Weld Heat Treatment Welded castings of type HX alloy usually are not given any post-weld heat treatment.

13


14


STEEL CASTINGS HANDBOOK Supplement 8 High Alloy Data Sheets Corrosion Series


Corrosion Resistant Type CA6NM (UNS J91540)

Description Type CA6NM is an iron-chromiumnickel-molybdenum alloy that is hardenable by heat treatment. It is similar in general corrosion resistance to type CA15, but the addition of nickel and molybdenum to the CA6NM composition improves its resistance to attack by sea water. Although the tensile strength properties of CA6NM are comparable to those of CA15, the impact strength is about twice as high, as is the resistance to damage from cavitation effects. Heavy sections and complex structures are cast in CA6NM with less difficulty than experienced with the CA15 alloy, and for cast-weld construction, or where field welding is involved, type CA6NM offers the advantage of not requiring a preheat. A major application of the alloy has been in large hydraulic turbine runners for power generation. The alloy normally is used in the normalized and tempered condition in which the microstructure is essentially 100 percent martensite. CA6NM can contain appreciable amounts of retained austenite because this structure provides the optimum combination of strength, ductility, hardness, and toughness. Variations in heat treatment can be selected to enhance one or more of these properties. Improved corrosion resistance, particularly resistance to sulfide stress corrosion, can be obtained with a lower carbon as in grade CA6NM Class B (ASTM A487). A lower carbon content, as in grade CA6NM Class B, permits heat treating to a lower maximum hardness (and strength) which results in improved corrosion resistance, particularly resistance to sulfide stress corrosion cracking. Castings of type CA6NM alloy have good machining and welding properties if proper techniques are employed. The alloy is magnetic and has a coefficient of thermal expansion slightly less than that of carbon steel. Thermal conductivity is

Chemical composition - % C Mn Si min. max. 0.060 1.00 1.00

P

S

0.040

0.030

Cr 11.5 14.0

Physical properties Modulus of elasticity, psi x 106 Density, lb/in3 Sp. Heat, Btu/lb.oF, at 70 oF Electrical resistivity, :S.m, at 70 oF Melting point, approximate oF Magnetic permeability

Ni 3.5 4.5

Mo 0.4 1.0

Fe bal

29.0 0.278 0.11 0.78 2750 Ferromagnetic

Thermal conductivity Btu/(ft.h. oF) ______________________

Mean coefficient of Linear thermal expansion : in./(in. oF) _______________________

At 212 oF At 1000 oF

70 - 212 oF 70 - 1000 oF

14.5 16.7

6.0 7.0

Mechanical properties at room temperature Representative tensile properties air cooled from >1900 oF temper at 11001150 oF _______________ Tensile strength, ksi Yield strength, 0.2% offset, ksi Elongation, in 2in., % Reduction of area, % Brinell hardness (HBW) Charpy V-notch, @ -100 oF, ft.lbs

120.0 100.0 24 60 268 -

Minimum tensile & toughness requirements ASTM A743, A757 ______________ 110.0 80.0 15 35 20/12 (A757)A

Toughness and impact properties Impact, Charpy V-notch - see Fig.1 Fracture toughness, Kic - see Fig.2 At elevated temperatures Short time elevated temperature properties - see Fig.3 Creep rupture properties - see Table 1 and Figs. 4 - 6 ______________________ A

20 ft.lb average on three specimens, 15 ft.lb minimum allowed on one specimen only

about 45 percent less than carbon steel but almost 60 percent greater than the CF alloy types. Electrical resistivity is about five times that of carbon steel. Heat Treatment The alloy is hardened by heating between 1900 and 1950°F (1038 to 1066°C) followed by cooling in either air or oil. After the castings have cooled below the martensite finish temperature, which varies with the compositional balance, they should be tempered as soon as possible. Depending on strength requirements, the alloy is tempered at 600°F (316°C) or more commonly in the range of 1100 to 1150°F (593 to 621°C). Tempering in the vicinity of 900°F (482°C) should be avoided because lower toughness will result. Some reaustenitization may occur if tempering temperatures above 1200°F (649°C) are employed, and upon cooling, the microstructure may contain untempered martensite. Double tempers are employed to achieve hardness values below 22 HRC for castings intended for wet H2S environments. A typical double temper heat treatment would consist of a 1250°F (677°C) temper followed by a 1125°F (607°C) temper. Highest strength and hardness are obtained by tempering at 600°F (316°C); however, impact strength is reduced by 50 percent and ductility is reduced to about 12 percent. Holding times for austenitizing and tempering will vary with the thickness of casting sections involved, but should be sufficiently long to heat all sections to a uniform temperature throughout. Applications The following lists of consuming industries, cast parts, and corrosive materials are useful as examples of typical applications where type CA6NM alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Chemical, Marine, Oilfield, Petroleum Refining, Pollution Control, Power Plant. Castings Casings, compressor impellers, diaphragms, diffusers, discharge spacers, Francis runners, hydraulic turbine parts, impulse wheels, packing housings, propellers, pump impellers, suction spacers, valve bodies and parts. Corrosives Boiler feed water [250°F (115°C)], sea water, steam, sulfur, water to 400°F (204°C). NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made to the extensive alphabetical lists of corrodents published by many alloy foundries and to corrosion data surveys published by the NACE to determine whether type CA6NM is suitable for the particular corrosive involved, and the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. The mechanical and physical property data presented in tabular and graphical form are representative for alloy CA6NM. These data are neither average nor minimum values, and should not be used for either specification or design purposes. Specification and/or design information may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in CA6NM alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Complex designs involving light and heavy sections are successfully made in this alloy, but drastic changes in section should be avoided as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allowance for this alloy is 1/4 inch per foot.

Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Welds in light sections and in unstressed areas can be made without preheating. Welding in the heat treated condition is generally preferred. For welding very heavy sections or highly stressed regions, castings may require preheating in the range of 212 to 350°F (100 to 176°C) and should be maintained at 300 to 500°F (176 to 260°C) during welding as a guideline. After welding, cool to at least 212°F (100°C) or below the martensite finish temperature prior to re-tempering at 1100 to 1150°F (593 to 621°C). Cooling through the range of 1100 to 950°F (593 to 266°C) should be as rapid as possible to avoid loss in toughness. Welding procedure utilizing SMAW technique is described in this section. Machining Most machining operations can be performed satisfactorily on castings of CA6NM alloy. The work-hardening rate of this grade is much lower than the iron-chromium-nickel types, but it is advisable in all cases that the tool be kept continually entering into the metal. Slow feeds, deep cuts, and powerful, rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Chips are stringy but not abrasive. Chip curlers are recommended for carbide tools. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy Cast ASTM: A743 (CA6NM), A757 (E3N), A487 (CA6NM), A352 (CA6NM). Wrought A-182, Grade F6NM.

Table 1 Creep-Rupture Properties for CA6NMB [Air cooled from above 1900°F (1038°C);Tempered at 1100-1150°F (593-621°C)] Rupture strength, ksi o

C

104 hrs

105 hrs

800

427

54.5

41.0

850

454

39.0

29.0

900

482

28.0

20.0

950

510

19.7

14.3

1000

538

14.2

10.1

F

o

Creep strength, ksi o

B

F

o

C

0.1%/1000 hrs.

0.01%/1000 hrs.

800

427

41.0

31.0

850

454

29.6

22.5

900

482

22.0

16.3

950

510

16.0

11.8

1000

538

11.8

--

"The Elevated Temperature Properties of Alloy CA6NM", G.V. Smith, CAST METALS FOR STRUCTURAL AND PRESSURE CONTAINMENT APPLICATIONS, ASME 1979.

Corrosion Resistant Type CA15 (UNS J91150)

Description Type CA15 is an iron-chromium alloy containing the minimum amount of chromium necessary to make the metal virtually rustproof, and is similar to the original "stainless steel" used for cutlery. In addition to good atmospheric corrosion resistance, the alloy provides excellent resistance to corrosion or staining by many organic media in relatively mild service. The alloy has a high hardenability so that a wide range of hardness (144 to about 400 BHN) and other mechanical properties may be obtained even in heavy sections. In the annealed condition, the ferrite matrix contains agglomerated carbide particles. Depending on the temperature of heat treatment, the hardened alloy exhibits a pearlitic to martensitic structure that results in a tough, erosion resistant material. Castings of type CA15 alloy have fairly good machining and welding properties if proper techniques are employed. For improved machinability, this grade is sometimes made with the addition of selenium. The alloy is magnetic and has a coefficient of thermal expansion less than that of carbon steel. Heat Treatment

Chemical composition, % C Mn Si min. max. 0.15 1.00 1.50 1 Mo not intentionally added

P

S

0.04

0.04

Cr 11.5 14.0

Ni

Mo

Fe

1.0

0.51

bal

Physical propeties Modulus of elasticity, psi x 106 Density, lb/in3 Sp. Heat, Btu/lb.oF, at 70 oF Electrical resistivity, :S.m, at 70 oF Melting point, approximate oF Magnetic permeability (at H = 100 Oersted) Thermal conductivity Btu/(ft.h. oF)

Mean coefficient of Linear thermal expansion : in./(in. oF) ______________________

______________________ At 212 oF At 1000 oF

29.0 0.275 0.11 0.56 2750 500

70 - 212 oF 70 - 1000 oF 70 - 1300 oF

14.5 16.7

5.5 6.4 6.7

Mechanical properties at room temperature Minimum tensile requirements ASTM A743

Representative values air cooled from 1800 oF Tempered at, oF

600 1100 1200 1450 _______________________________ _________

Tensile strength, ksi 200 Yield strength, 0.2% offset, ksi 150 Elongation, in 2 in % 7 Reduction of area, % 25 Brinell hardness (HBW) 390 Charpy, keyhole, ft.lbs 15

135

115

100

90

115 17 55 260

100 22 55 225

75 30 60 185

65 18 30

To obtain maximum softness, castings of type CA15 alloy may be annealed at a 1450°F (788°C) minimum, usually 1550 to 1650°F (843 to 899°C), and slowly 10 20 35 furnace cooled. The alloy is hardened by heating to 1800 to 1850°F (982 to a 241 max. unless otherwise specified 1010°C), and cooling in oil or air. After hardening, castings should be tempered At elevated temperatures as soon as possible at 600°F (316°C) Short-time elevated temperature tensile properties - See Fig. 1 maximum, or in the range 1100 to 1500°F (593 to 816°C). Tempering in the vicinity of 900°F (482°C) should be avoided because low impact strength will result. Highest strength and hardness is obtained by tempering at 600°F (316°C) or below, and the alloy has best corrosion resistance in this fully hardened condition. When tempered above 1100°F (593°C), castings have improved ductility and impact strength, but corrosion resistance

is somewhat decreased. Poorest corrosion resistance results from tempering around 1100°F (593°C). Holding times for hardening and tempering will vary with the thickness of casting sections involved, but should be sufficiently long to heat all sections to a uniform temperature throughout. Applications The following lists of consuming industries, cast parts, and corrosive materials are useful as examples of typical applications where type CA15 alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Aircraft, Architecture, Chemical Processing, Food Processing, Marine, Oil Refining, Metallurgical, Power Plant, Pulp and Paper. Castings Burning torch gas distributor heads, bushings and liners, catalyst trays, fittings, furnace burner tips and pilot cones, gears, hydrafiner parts, impellers, jet engine components, letters, plaques, pump casings, railings, shafts, ship propellers, skimmer ladles, stuffing boxes, turbine blades, valve bodies, valve trim. Corrosives Abrasive chemicals, alkaline liquors, ammonia water, atmosphere, boiler feed water, brass dross, coke oven gas, corrosive oils at high pressures and temperatures, food products, oxidizing acids, pulp, sodium carbonate, sodium nitrate, steam. NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made to the extensive alphabetical lists of corrodents published by many alloy foundries and to corrosion data surveys published by the NACE to determine whether type CA15 is suitable for the particular corrosive involved, and the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. The mechanical and physical property data presented in tabular and graphical form are representative for alloy CA15. These data are neither average nor minimum values, and should not be used for either specification or design purposes. Specification and/or design information may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in CA15 alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Some difficulty is encountered in running thin sections, however, and designs involving appreciable changes in section should be avoided. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Unless the hardness and strength attainable with CA15 (or physical properties such as expansion coefficient or heat conductivity) are required, consideration should be given to other grades when designs are intricate. Normally used patternmakers' shrinkage allowance for this alloy is 1/4 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type CA15 castings can be welded by metal-arc, inert-gas arc, and oxyacetylene gas methods. Metal-arc is most frequently used. Oxyacetylene welding is not advisable because of possible impairment of corrosion resistance caused by carbon pick-up. Castings should be heated in the range 400 to 600°F (204 to 316°C) before welding. After welding, cool to not less than 300°F (149°C), heat to 1125 to 1400°F (607 to 760°C), hold until uniform temperature throughout, then air cool.

Welding procedures utilizing SMAW, GMAW and GTAW techniques are described in this section. Machining Most machining operations can be performed satisfactorily on castings of CA15 alloy. The workhardening rate of this grade is much lower than the iron-chromium-nickel types, but it is advisable in all cases that the tool be kept continually entering into the metal. The alloy should not be too soft; hardness of about 225 BHN is recommended. Slow feeds, deep cuts, and powerful, rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Chips are stringy but not abrasive. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is recommended for high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy Cast ASTM: A217 (CA15), A426 (CFCA15), A743 (CA15), A487 (CA15), SAE 60410, MIL-S 16993A(1), AMS 5351B. Wrought AISI 410.

Corrosion Resistant Type CA40 (UNS J91153)

Description

Type CA40 is an iron-chromium alloy similar to type CA15, but its higher carbon content permits hardening this grade to a maximum of about 500 BHN. Corrosion resistance and other characteristics are about the same as for the lower carbon CA15 alloy. Heat Treatment To obtain maximum softness, castings of type CA40 alloy may be annealed at 1450°F (788°C) minimum, usually 1550 to 1650°F (843 to 899°C), and slowly furnace cooled. The alloy is hardened by heating to 1800 to 1850°F (982 to 1010°C), and cooling in oil or air. After hardening, castings should be tempered as soon as possible at 600°F (316°C) maximum, or in the range 1100 to 1500°F (593 to 816°C). Tempering in the vicinity of 900°F (482°C) should be avoided. Highest strength and hardness is obtained by tempering at 600°F (316°C) or below, and the alloy has best corrosion resistance in this fully hardened condition. When tempered above 1100°F (593°C), castings have improved ductility and impact strength, but corrosion resistance is somewhat decreased. Poorest corrosion resistance results from tempering around 1100°F (593°C). Holding times for hardening and tempering will vary with the thickness of casting sections involved, but should be sufficiently long to heat all sections to a uniform temperature throughout. Applications

Chemical composition, % C Mn Si min. 0.20 max. 0.40 1.00 1.50

P

S

0.04

0.04

Cr 11.5 14.0

Ni

Mo

Fe

1.0

0.51

bal

1

Mo not intentionally added

Physical properties Modulus of elasticity, psi x 106 Density, lb/in3 Sp. Heat, Btu/lb.oF, at 70 oF Electrical resistivity, :S.m, at 70 oF Melting point, approximate oF Magnetic permeability (at H = 100 Oersted) Thermal conductivity Btu/(ft.h. oF)


______________________ At 212 oF At 1000 oF

29.0 0.275 0.11 0.56 2750 500

70 - 212 oF 70 - 1000 oF 70 - 1300 oF

14.5 16.7

5.5 6.4 6.7

Mechanical properties at room temperature Minimum tensile requirements ASTM A743

Representative values air cooled from 1800 oF Tempered at, oF

600 1100 1200 1450 _______________________________ _________

Tensile strength, ksi Yield strength, 0.2% offset, ksi

200

135

115

100

90

150 Elongation, in 2 in % 7 Reduction of area, % 25 Brinell hardness (HBW) 390 Charpy, keyhole, 1 ft.lbs

115 17 55 260 2

100 22 55 225 4

75 30 60 185 3

65 18 30 2692 -

The following lists of consuming industries, cast parts, and corrosive materials are useful as examples of 2 Maximum typical applications where type CA40 alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses.

Industries Food Processing, Glass, Oil Refining, Power Plants, Pulp and Paper. Castings Choppers, cutting blades, cylinder liners, dies, grinding plugs, hot oil plungers, flow control, molds, pump parts, casings, impellers, pump sleeve, shredder sleeves, steam turbine parts, valve trim, seat rings, and wedges. Corrosives Air, abrasives, dilute oxidizing acids, food products, glass, oxidizing atmosphere to 1200°F, sour crude oil (hot, high pressure), steam. NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made to the extensive alphabetical lists of corrodents published by many alloy foundries and to corrosion data surveys published by the NACE to determine whether type CA40 is suitable for the particular corrosive involved, and the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. The mechanical and physical property data presented in tabular and graphical form are representative for alloy CA40. These data are neither average nor minimum values, and should not be used for either specification or design purposes. Specification and/or design information may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in CA40 alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Some difficulty is encountered in running thin sections, however, and designs involving appreciable changes in section should be avoided. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Unless the hardness and strength attainable with CA40 (or physical properties such as expansion coefficient or heat conductivity) are required, consideration should be given to other grades when designs are intricate. Normally used patternmakers' shrinkage allowance for this alloy is 1/4 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type CA40 castings can be welded by metal-arc, inert-gas arc, and oxyacetylene gas methods. Metal-arc is most frequently used. Oxyacetylene welding is not advisable because of possible impairment of corrosion resistance caused by carbon pick-up. Castings should be heated in the range 400 to 600°F (204 to 316°C) before welding. After welding, cool to not less than 300°F (149°C), heat to 1125 to 1400°F (607 to 760°C), hold until uniform temperature throughout, then air cool. The welding procedures outlined for alloy CA15 are applicable to alloy CA40. Welding procedures utilizing SMAW, GMAW and GTAW techniques are described in this section. Machining Most machining operations can be performed satisfactorily on castings of CA40 alloy. The workhardening rate of this grade is much lower than the iron-chromium-nickel types, but it is advisable in all cases that the tool be kept continually entering into the metal. Hardness of about 225 BHN is recommended. Slow feeds, deep cuts, and powerful, rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Chips are stringy and abrasive to tools. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur

and about 8 to 10 percent fatty oil is recommended for high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast ASTM: A743 (CA40), SAE 60420. Wrought AISI 420.

Corrosion Resistant Type CB7Cu (UNS J92110 [CB7Cu-2]) (UNS J92180 [CB7Cu-1])

Description Type CB7Cu is a high strength, precipitation hardenable iron-chromium-nickel-copper alloy having corrosion resistance intermediate between the non-hardenable austenitic type CF alloys and the hardenable martensitic type CA grades. Castings of type CB7Cu have good resistance to atmospheric corrosion and many aqueous corrodents including sea water, food products, and paper mill liquors. Because of the range of mechanical properties attainable, the alloy finds wide application in service requiring both corrosion resistance and high strength at temperatures up to 600°F (316°C). It is especially useful where machining is involved since the work can be done when castings are in the solution annealed condition. Subsequent precipitation hardening to the desired mechanical strength may then be conducted at relatively low temperature so that there is little danger of cracking, distortion or oxidation of the machined surfaces. As shown in the table of properties, the broad alloy type covers two sub-grades differing only in chromium and nickel contents. Although the mechanical properties are essentially the same for both grades, the 15 Cr, 4 Ni type CB7Cu-2 retains ductility somewhat better than the 17 Cr, 4 Ni type as thickness increases. For this reason, it is useful for parts with heavy sections. In the solution annealed state, the microstructure of the alloy consists of martensite formed upon cooling the casting from the solution temperature at which the original as-cast structure was austenite containing dissolved copper. This copper remains in the martensite as a super-saturated solution but, if the alloy is later reheated to the range 9001150°F (482-621°C), it precipitates submicroscopically and substantially increases the strength and hardness of the casting. Castings of type CB7Cu alloy have good machining and welding properties if proper techniques are employed. The alloy has a low coefficient of thermal expansion similar to

Chemical composition, % C CB7Cu-1 min. max. 0.07 CB7Cu-2

CB7Cu-1 CB7Cu-2

Mn

Si

P

S

0.70

1.00

0.035

0.03

Cr 15.50 17.70 14.00 15.50

min. max.

0.07

0.70

1.00

0.035

0.03

Ni 3.60 4.60

Cu 2.50 3.20

Cb1 0.20 0.35

N

Fe

min. max.

0.05

bal

min. max.

4.50 5.50

2.50 3.20

0.20 0.35

0.05

bal

1

o

Cb not added when alloy is to be hardened by 900 F aging treatment

Physical properties Modulus of elasticity, psi x 106 Density, lb/in3 Sp. Heat, Btu/lb.oF, at 70 oF Electrical resistivity, :S.m, at 70 oF Melting point, approximate oF Magnetic permeability (at H = 100 Oersted)

28.52 0.280 0.11 0.77 2750 ferromagnetic

2

See Fig.1 for effect of temperature on modulus

Thermal conductivity Btu/(ft.h. oF) ______________________


At 212 oF At 500 oF At 860 oF At 900 oF

Aged at 70 - 200 oF 70 - 400 oF 70 - 600 oF 70 - 800 oF

9.9 11.3 13.0 13.1

900 oF 6.0 6.1 6.3 6.5

1100oF 6.6 6.9 7.1 7.2

Mechanical properties at room temperature Representative values air cooled from 1925 oF Aged at, oF Tensile strength, ksi Yield strength, 0.2% offset, ksi

900 925 1025 1075 1100 1150 ________________________________________ 187

189

165

155

145

140

161 Elongation, in 2 in % 10 Reduction of area, % 21 Brinell hardness (HBW) 412 Impact, Charpy V ft.lbs 7

165 11 26 412

158 14 35 350

141 14 35 319

132 15 39 315

120 16 42 307

12

22

27

30

37

Minimum requirements - ASTM A747 Aged at, oF Tensile strength, ksi Yield strength, 0.2% offset, ksi

900 925 1025 1075 1100 1150 ________________________________________ 170

175

150

145

135

125

145 Elongation, in 2 in % 5 Reduction of area, % Brinell hardness (HBW) 412 Impact, Charpy V ft.lbs -

150 5 412

140 9 350

115 9 319

110 9 315

97 10 307

-

-

-

-

at Elevated temperatures - see Fig.2

-

the type CA alloys. Electrical resistance is about five times that of carbon steel and thermal conductivity is 40 percent less. Because the alloy is ferromagnetic, magnetic particle testing is sometimes used for nondestructive inspection. If minor amounts of non-magnetic retained austenite occur in the form of stringers, or if untransformed ferrite stringers are present, false linear indications may be obtained. (The type CB7Cu-2 is less susceptible than the type CB7Cu-1 alloy to ferrite stringer formation.) Such stringers do not in any way affect the soundness of the casting. It is preferable to use dye penetrant or fluorescent dye inspection instead of magnetic particle for testing this alloy. Heat Treatment Type CB7Cu castings are supplied in either the solution annealed or hardened condition, depending on the desire of the user. Solution annealing consists of heating the castings to 1925°F (1050°C) ± 50°F (30°C), holding them for 30 minutes per inch of the heaviest section (30 minutes minimum), and then cooling them to below 90°F (30°C). To ensure complete transformation of austenite, it is occasionally necessary to cool the castings in dry ice. Prior to solution annealing, castings sometimes are specified to be given a homogenizing heat treatment consisting of heating the castings to 1900°F (1040°C) minimum, holding them 1.5 hours minimum, and then cooling them to below 90°F (30°C). Castings of type CB7Cu alloy are intended to be used only in the precipitation hardened condition, but may be supplied in the solution annealed condition if machining is to be done prior to hardening. Precipitation hardening involves heating the solution annealed castings: a) at 900°F (480°C) for 1 hour; b) at 925°F (495°C) for 1.5 hours; or c) at 1025°F (550°C), 1075°F (580°C), 1100°F (595°C) or 1150°F (620°C) for 4 hours. After the required time at temperatures the castings are air cooled. Because of the expansion that occurs when austenite transforms to martensite, it is advisable to avoid steep thermal gradients in castings when they are cooling from the solution annealing temperature. Lack of attention to this may result in cracking of the surfaces that cooled earliest on the casting. A dimensional change also takes place upon hardening and should be given consideration when large castings in the solution annealed condition are to be machined to close tolerances prior to hardening. This change is a contraction of 0.0004 to 0.0006 inch per inch. Applications The following lists of consuming industries, cast parts, and corrosive materials are useful as examples of typical applications where type CB7Cu alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Aerospace, Aircraft, Chemical, Food Processing, Gas Turbine, Marine, Petrochemical, Pulp and Paper. Castings Airframe components, centrifuge bowls, compressor impellers, food machinery parts, machine tool parts, propeller shafts, pump impellers, rotors, screw flights, valve bodies, discs, and trim. Corrosives Air, ethylene glycol-water (-65 to 200°F), food products, pulp liquor, sea water, water (up to 400°F). NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made to the extensive alphabetical lists of corrodents published by many alloy foundries and to corrosion data surveys published by the NACE to determine whether type CB7Cu is suitable for the particular corrosive involved, and the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. The mechanical and physical property data presented in tabular and graphical form are representative for alloys

CB7Cu-1 and CB7Cu-2. These data are neither average nor minimum values, and should not be used for either specification or design purposes. Specification and/or design information may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in CB7Cu alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Complex designs involving light and heavy sections are successfully made in this alloy, but drastic changes in section should be avoided as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allowance for this alloy is 1/4 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type CB7Cu castings can be welded by shielded metal-arc, inert-gas arc, and oxyacetylene gas methods. Oxyacetylene welding is not advisable because of possible impairment of both corrosion resistance and mechanical properties caused by carbon pick-up. In either the annealed or overaged condition (i.e., 1000°F or over), castings can be welded without preheat, although it is sometimes desirable to preheat to 500°F (260°C) when welding heavy sections. Sections which require multiple-pass welds are handled better in the annealed condition than after aging because the prolonged heat of welding will introduce non-uniform hardening characteristics to the weld zone. Thus, after welding, such castings may require a solution heat treatment in the temperature range 1875-1975°F (1024-1079°C) followed by rapid cooling before being hardened by reheating to the precipitation temperature. Only the aging treatment is needed to harden the weld zone on single pass welds. Castings having a copper content near the high end of the copper range may suffer underbead cracking when welded. Accordingly, when castings are intended to be welded, it is desirable to have the copper content below 3.00 percent. Welding procedures utilizing SMAW, GMAW and GTAW techniques are described in this section. Machining Most machining operations can be performed satisfactorily on castings of CB7Cu alloy. It is important in all cases that the tool be kept continually entering into the metal in order to avoid work-hardening the surface from rubbing or scraping. Slow feeds, deep cuts, and powerful, rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Type CB7Cu castings can be machined in either the annealed or hardened condition. An advantage of this alloy is that it can be machined in the annealed condition and later hardened by a low temperature heat treatment with minimal scaling or distortion. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is recommended for high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Localized heating such as resulting from heavy grinding or abrasive wheel cutting may cause castings to crack. For this reason, cold sawing is preferred for cutting, and care should be taken to avoid overheating during grinding operations. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26.

Casting designations, specifications, and corresponding wrought alloy The wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast ASTM: A747 (CB7Cu-1 and CB7Cu-2); AMS 5398B. Wrought 17-4PH; 15-5PH.

Corrosion Resistant Type CB30 (UNS J91803)

Description Type CB30 is an iron-chromium alloy sufficiently high in chromium content to provide excellent resistance to corrosion by nitric acid, alkaline solutions, and many organic chemicals. Maximum corrosion resistance is obtained when the carbon content is held below 0.20 percent, but the alloy is normally made with carbon 0.20 to 0.30 percent in order to improve castability. The alloy maintains predominantly ferritic structure, and even at the higher carbon levels only a small amount of ferrite transforms at elevated temperature to austenite for subsequent change to martensite upon cooling. Thus, in contrast to the hardenable CA15 grade, the CB30 type is practically non-hardenable by heat treatment. By balancing the composition toward the low end of the chromium and the high end of the nickel and carbon ranges, however, the hardening characteristics of the alloy are increased. In this case, the grade corresponds more nearly to the wrought alloy AISI type 431, whereas normally the properties of the alloy correspond to those of AISI type 442. Castings of the type CB30 alloy have fair ductility, but poor impact strength. They are readily machinable and can be welded successfully if proper technique is employed. The alloy is magnetic and has a lower coefficient of thermal expansion than carbon steel. Heat Treatment


P

S

0.04

0.04

Cr 18 21

Physical properties Modulus of elasticity, psi x 106 Density, lb/in3 Sp. Heat, Btu/lb.oF, at 70 oF Electrical resistivity, :S.m, at 70 oF Melting point, approximate oF Magnetic permeability Thermal conductivity Btu/(ft.h. oF) ______________________ At 212 oF At 1000 oF

12.8 14.5

Fe

2.0

bal

29.0 0.272 0.11 0.76 2725 Ferromagnetic Mean coefficient of Linear thermal expansion : in./(in. oF) ______________________ 70 - 212 oF 70 - 1000 oF 70 - 1300 oF

Mechanical properties at room temperature Representative values1 Annealed at 1450 oF F.C. to 1000 oF then A.C. _______________ Tensile strength, ksi 95.0 Yield strength, 0.2% offset, ksi 60.0 Elongation, in 2in., % 15 Brinell hardness (HBW) 195 Charpy V-notch, @ -100 oF, ft.lbs Toughness and impact properties ________________________________

Ni

5.7 6.5 6.7

Minimum tensile requirements

ASTM A743 ______________ 65.0 30.0 2

1

Values may vary considerably depending on composition balance and heat treatment 2 241 max unless otherwise specified

Type CB30 castings are normally supplied in the annealed condition. Annealing consists of heating to 1450°F (788°C) minimum, furnace cooling to about 1000°F (538°C), then air cooling. Holding time at temperature will vary with the thickness of casting sections involved, but should be sufficiently long to heat all sections to a uniform temperature throughout. Applications The following lists of consuming industries, cast parts, and corrosive materials are useful as examples of typical applications where type CB30 alloy has been employed successfully; they are not comprehensive, nor are they

intended as guides to alloy selection for specific end uses. Industries Chemical Processing, Food Processing, Heat Treating, Oil Refining, Ore Roasting, Power Plants. Castings Furnace brackets and hangers, pump parts, rabble arms, tube supports, valve bodies, valve parts. Corrosives Food products, hot ore, nitric acid, oil, oxidizing atmospheres to 1400°F (760°C), steam, sulfur atmospheres. NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made to the extensive alphabetical lists of corrodents published by many alloy foundries and to corrosion data surveys published by the NACE to determine whether type CB30 is suitable for the particular corrosive involved, and the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. The mechanical and physical property data presented in tabular and graphical form are representative for alloy CB30. These data are neither average nor minimum values, and should not be used for either specification or design purposes. Specification and/or design information may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in CB30 alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Some difficulty is encountered in running thin sections, however, and designs involving appreciable changes in section should be avoided. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. If toughness is an important requirement, consideration should be given to one of the CF, CH or CK grades unless the greater thermal expansion of these alloys cannot be tolerated. Normally used patternmakers' shrinkage allowance for this alloy is 1/4 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type CB30 castings can be welded by metal-arc, inert-gas arc, and oxyacetylene gas methods. Metal-arc is most frequently used. Oxyacetylene welding is not advisable because of possible impairment of corrosion resistance caused by carbon pick-up. Castings should be heated in the range 600 to 800°F (316 to 427°C) before welding. After welding, cool to 150°F (666°C) or lower, heat to 1450°F (788°C) minimum, hold until uniform temperatures throughout, then air cool. Machining Most machining operations can be performed satisfactorily on castings of CB30 alloy. The workhardening rate of this grade is much lower than the iron-chromium-nickel types, but it is advisable in all cases that the tool be kept continually entering into the metal. Slow feeds, deep cuts, and powerful, rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Chips are short and brittle. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is recommended for high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools.

Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast ASTM: A743 (CB30); SAE 60442. Wrought AISI 442.

Corrosion Resistant Type CC50 (UNS J92615)

Description Type CC50 is an iron-chromium alloy containing about 28 percent chromium and up to 4 percent nickel. It provides excellent resistance to dilute sulfuric acid in mine waters, mixed nitric and sulfuric acids, and oxidizing acids of all types. The alloy has a ferritic structure at all temperatures and for this reason cannot be hardened by heat treatment. The ductility and impact strength are very low unless some nickel is present. In the CC50 type containing over 2 percent nickel, substantial improvement in the strength and ductility is obtained by increasing the nitrogen content to 0.15 percent or more. Castings of the type CC50 alloy are readily machinable. They can be welded successfully if proper technique is employed. The alloy is magnetic and has a lower coefficient of thermal expansion than carbon steel.


Applications

S

0.04

0.04

Cr 26 30

Physical properties Modulus of elasticity, psi x 106 Density, lb/in3 Sp. Heat, Btu/lb.oF, at 70 oF Electrical resistivity, :S.m, at 70 oF Melting point, approximate oF Magnetic permeability Thermal conductivity Btu/(ft.h. oF)

Ni

Fe

4.0

bal

29.0 0.272 0.12 0.77 2725 Ferromagnetic

______________________



70 - 212 oF 70 - 1000 oF

12.6 17.9

5.9 6.4

Mechanical properties at room temperature Representative values Annealed at 1450 oF F.C. to 1000 oF then Air Cool As Cast (a)1____(b)2___(b)2_

Heat Treatment Type CC50 castings are normally supplied in the annealed condition. Annealing consists of heating to 1450°F (788°C) minimum followed by air or furnace cooling. Holding time at temperature will vary with the thickness of casting sections involved, but should be sufficiently long to heat all sections to a uniform temperature throughout. Heating in the range 850 to 950°F (454 to 510°C) will result in a significant loss of ductility and toughness.

P

Tensile strength, ksi 70.0 Yield strength, 0.2% offset, ksi 65.0 Elongation, in 2in., % 2 Brinell hardness (HBW) 212 Impact, Izod V-notch, ft.lbs. 2 ________________________________

95.0 60.0 15 193 45

97.0 65.0 18 210 -

Minimum tensile requirements ASTM A743 _____________ 55.0 -

1

(a) Under 1.0% Ni (b) Over 2.0% Ni with 0.15% N min.

2

The following lists of consuming industries, cast parts, and corrosive materials are useful as examples of typical applications where type CC50 alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Chemical Manufacturing, Mining, Pulp and Paper, Synthetic Fibre Manufacturing. Castings Bushings, cylinder liners, digester parts, pump casings and impellers, valve bodies, valve seats.

Corrosives Acid mine water, alkaline liquors, nitric acid, sulfurous liquors. NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made to the extensive alphabetical lists of corrodents published by many alloy foundries and to corrosion data surveys published by the NACE to determine whether type CC50 is suitable for the particular corrosive involved, and the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. The mechanical and physical property data presented in tabular and graphical form are representative for alloy CC50. These data are neither average nor minimum values, and should not be used for either specification or design purposes. Specification and/or design information may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in CC50 alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Some difficulty is encountered in running thin sections, however, and designs involving appreciable changes in section should be avoided. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. If toughness is an important requirement, consideration should be given to one of the CF, CH or CK grades unless the greater thermal expansion of these alloys cannot be tolerated. Normally used patternmakers' shrinkage allowance for this alloy is 1/4 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type CC50 castings can be welded by metal-arc, inert-gas arc, and oxyacetylene gas methods. Metal-arc is most frequently used. Oxyacetylene welding is not advisable because of possible impairment of corrosion resistance caused by carbon pick-up. Castings should be heated in the range 400 to 1300°F (204 to 704°C) before welding. After welding, heat to 1550 to 1900°F (879 to 1038°C), hold until uniform temperature throughout, then air cool. The welding procedures outlined for alloy HC are applicable to alloy CC50. Welding procedures utilizing SMAW, and GTAW techniques are described in this section. Machining Most machining operations can be performed satisfactorily on castings of CC50 alloy. The workhardening rate of this grade is much lower than the iron-chromium-nickel types, but it is advisable in all cases that the tool be kept continually entering into the metal. Slow feeds, deep cuts, and powerful, rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Chips are short and brittle. Local overheating caused by dull tools or excessive speed may result in cracking the work. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26.

Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast ASTM: A743 (CC50); SAE 60446. Wrought AISI 446.

Corrosion Resistant Types Duplex Stainless Steels;

CD4MCu (UNS J93370), CD4MCuN (UNS J93372), CD3MCuN (J93373),CE8MN (UNSJ93371), CD3MN (UNSJ92205),

Super Duplex Stainless Steels; CE3MN (UNS93404), CD3MWCuN (J93380) Description This data sheet includes both duplex stainless steels and super duplex stainless steels. The difference between duplex stainless steels (DSS) and super duplex stainless steels (SDSS) is a function of the Pitting Resistance Number (PREN). The PREN is a function of the chromium, molybdenum and nitrogen content. For SDSS the PREN is generally 40 or higher. Chemical composition - % ASTM A890 CD4MCu

1

CD4MCuN

1

CD3MCuN1 CE8MN1

C

Mn Si

Ni

Mo

Cu W

4.75 6 4.7 6

1.75 2.25 1.7 2.3

2.7 3.3 2.7 3.3

0.1 0.25

5.6 2.9

1.4

0.22

max. 0.03 1.2 1.1 0.03 0.03 26.7 6.7 3.8

1.9

0.33

min. max. 0.04 1 min. max. 0.04 1

CD3MN

24.5 0.04 0.04 26.5 24.5 0.04 0.04 26.5

1.5 0.04 0.04 25.5 11

min. 1

min.

4.5

0.3

1.75

0.15

0.04 0.04 27

6

2.5

0.25

max. 0.03 1.5 1 1

4.5 2.5

0.04 0.02 23.5 6.5 3.5 0.04 0.04 26

6

4

8

Fe

UTS

YS

Elong.

bal

ksi 100

ksi 70

% 16

bal

95

65

25

bal

95

65

25

bal

90

60

25

bal

100

75

18

bal

100

65

25

bal

100

70

16

bal

100

65

25

0.1

4

24

CD3MWCuN2 min.

3

N

24 21

min.

max. 0.03 1

Cr

22.5 8

max. 0.03 1.5 1 CE3MN2

S

24

min.

max. 0.06 1 1

1

min.

max. 0.08 1 CD6MN1

1

P

0.1 1

0.3 0.1

5

0.3

24

6.5 3

0.5 0.5 0.2

0.03 0.025 26

8.5 4

1

1

0.3

1

DSS 2 SDSS

It should be recognized that the ferrite balance of duplex alloys must be controlled to avoid cracking during processing and welding. To this end nitrogen levels must be controlled. ASTM has addressed this issue by introducing CDMCuN into A890. Although CD4MCu still exists in A890 it is strongly recommended that CD4MCuN be substituted for this grade. Type CD4MCuN is an iron-chromium-nickel-copper-molybdenum alloy having corrosion resistance in many media superior to the CF8 and CF8M types, but having about double the yield strength of those alloys. Combining good ductility with high hardness, castings of type CD4MCuN alloy have excellent resistance to environments involving abrasion or erosion-corrosion. The alloy also shows exceptional resistance to stresscorrosion cracking in chloride-containing solutions or vapors, and is usefully employed in handling both oxidizing and reducing corrodents. As cast, these alloys have a two-phase, ferrite plus austenite structure. Because of the low carbon content (0.04 percent maximum), there are only small amounts of chromium carbides distributed throughout the matrix, but for maximum corrosion resistance, these must be dissolved by suitable heat treatment. Generally these alloys are used only in the solution annealed condition, aging of these grades will result in a loss of ductility and toughness. Elevated temperature applications in the range 500 to 950°F (260 to 510°C) should be avoided

because long time heating at this range will result in a serious loss of ductility and toughness. Castings of these types have good machining and welding characteristics. Thermal expansion of this alloy is about 20 percent greater than for carbon steel, but about 30 percent less than for the CF alloy types. Thermal conductivity and electrical resistivity are comparable to the CF alloys and are roughly five times the values for carbon steel. The alloys are ferromagnetic.

Physical properties CD4MCu Modulus of elasticity, psi x 106 Density, lb/in3 Sp. Heat, Btu/lb.oF, at 70 oF Electrical resistivity, :S.m, at 70 oF Melting point, approximate oF Magnetic permeability Thermal conductivity Btu/(ft.h. oF) ______________________ At 212 oF At 1000 oF

8.8 13.4

2700

29.0 0.28 0.11 0.75 Ferromagnetic

Mean coefficient of Linear thermal expansion : in./(in. oF) ______________________ 70 - 212 oF 70 - 600 oF 70 - 1000 oF 70 - 1200 oF

6.3 6.6 6.9 7.0

Additional properties at room temperature, CD4MCu Representative values Water quenched From 1900 oF __________________

Tensile strength, ksi 108.0 Heat Treatment Yield strength, 0.2% offset, ksi 81.5 For complete solution of Elongation, in 2in., % 25 Reduction of Area, % 45 carbides and maximum Brinell hardness (HBW) 253 corrosion resistance, castings Charpy V-notch see figs.1a and 1b at Elevated temperatures see fig.2 should be heated for a sufficient time to be uniformly at the temperatures shown in Table 1, and quenched in water, oil or air. The temperature from which castings are quenched should be as close to the high side of the previously stated range as is consistent with avoidance of cracking for the casting configuration involved. Time to attain solution temperature will vary with the thickness of casting sections, and should be sufficiently long to heat all sections to a uniform temperature throughout.

The solution treatment temperature shown in Table 1 have been shown to be adequate in dissolving all carbides and intermetallic precipitates. The lower hold temperatures mentioned in Table 1 do not appear to impart any improvement in processing capability or properties of these grades. Applications The following lists of consuming industries, cast parts, and corrosive materials are useful as examples of typical applications where these alloys has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Chemical Processing, Marine, Municipal Water Supply, Naval, Paint, Petroleum Refining, Power Plant, Pulp and Paper, Soap Manufacturing, Textile, Transportation. Castings Compressor cylinders, digester valves, feed screws, impellers, liners, pump casings, runway light fixtures (aircraft carriers, airports), safety valves, seal rings (centrifugal pumps), valve parts. Corrosives Concentrated brine, fatty acids, potable water, pulp liquors at 220°F (104°C), sea water, steam, sulfuric acid [15-30% at 140-160°F (60-71°C)], sulfuric acid [35-40% at 185°F (85°C) plus 5% organics], titanium dioxide plus sulfuric acid solution, titanium sulfate. NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made

to an experienced high alloy foundry and to corrosion data surveys published by the NACE to determine whether DSS and SDSS alloys are suitable for the particular corrosive involved, and the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. The methods in ASTM A923 may be used to determine the presence of detrimental intermetallic precipitates in various duplex stainless steels. The mechanical properties are taken from ASTM. The physical property data presented in tabular and graphical form are representative for the alloy CD4MCu. These data are neither average nor minimum values, and should not be used for either specification or design purposes. Specification and/or design information may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily. Somewhat lighter sections are feasible depending on casting design and pattern equipment. This alloy permits designs involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allowance for this alloy is 1/4 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the molding method and by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding DSS and SDSS castings can be welded with shielded metal-arc and inert-gas arc methods. Matched or overmatched filler metals may be used. Preheating is not required. Matched fillers have a composition which is similar to the base metal and will require post weld heat treatment in accordance with Table 1. Overmatched fillers have approximately 2% more nickel than the base metal to balance the ferrite content due to the high cooling rates of the weld metal. Overmatched rods are particularly suitable for conditions where postweld heat treatment may not be possible such as very large castings of field welds. Having said this it is not uncommon for foundries to carry out a post weld heat treatment on welds made with overmatching fillers. This requirements for post weld heat treatment is often made by customers and specifications. Machining Most machining operations can be performed satisfactorily on DSS and SDSS castings. It is important in all cases that the tool be kept continually entering into the metal in order to avoid work-hardening the surface. Slow feeds, deep cuts, and powerful, rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Because chips are tough and stringy, chip curler tools are recommended. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is recommended for high speed tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Castings Handbook, 6th Edition, Chapter 26.

Casting designations, specifications, and corresponding wrought alloys The American Iron and Steel Institute wrought alloy designations are listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of casting

Cast (ASTM) A890 - CD4MCu, CD4MCuN, A995 - CD4MCuN

Wrought (UNS) S32550

A890 - CD3MCuN A890, A995 - CE8MN, A890, A995 - CD3MN,

S39205

A890, A995 - CE3MN

S32750

A890, A995 - CD3MWCuN

S32760

Table 1: Heat treatment Requirements Grade

Heat Treatment

CD4MCu, CD4MCuN, CD3MCuN

Heat to 1900°F (1040°C) minimum, hold for sufficient time to heat casting uniformly to temperature, quench in water or rapid cool by other means.

CE8MN


CD6MN


CD3MN

Heat to 2050°F (1120°C) minimum, hold for sufficient time to heat casting uniformly to temperature and water quench, or the casting may be furnace cooled to 1850°F (1010°C) minimum, hold for 15 min minimum and then water quench. A rapid cool by other means may be employed in lieu of water quench.

CE3MN

Heat to 2050°F (1120°C) minimum, hold for sufficient time to heat casting to temperature, furnace cool to 1910°F (1045°C) minimum, quench in water or rapid cool by other means.

CD3MWCuN

Heat to 2010°F (1100°C) minimum, hold for sufficient time to heat casting uniformly to temperature, quench in water or cool rapidly by other means.

Corrosion Resistant Type CE30 (UNS J93423)

Description Type CE30 is an iron-chromium-nickel alloy high in chromium but containing sufficient nickel to provide better strength and ductility than can be obtained with the high chromium CC50 type. The alloy is particularly resistant to sulfurous acid and sulfites in the paper industry, dilute sulfuric acid with sulfurous acid, and sulfuric with nitric acid. (Please note that the composition of the heat resistant alloy, type HE, having a carbon content range of 0.20 percent to 0.50 percent and a manganese content of 2.00 percent max., overlaps that of corrosion resistant alloy, type CE30). In the as-cast condition, the alloy has a two-phase, austenite plus ferrite structure containing carbides. The high chromium content and the duplex structure permit a fairly high carbon content without serious loss of corrosion resistance when the alloy is exposed to temperatures in the carbide precipitation range, 800 to 1600°F (427 to 871°C). For this reason, the alloy is useful where castings cannot be heat treated effectively, or where they must be welded without subsequent heat treatment. Long exposure in the range 800-900°F (427-482°C) and 1500-1600°F (816871°C), however, will result in a significant loss of toughness. This loss of toughness increases with increasing ferrite content. On the other hand, resistance to stress-corrosion cracking by chlorides and by polythionic acid increases with increasing ferrite content. Type CE30 cannot be hardened by heat treatment, but the ductility and corrosion resistance can be improved somewhat by quenching the alloy from about 2000°F (1093°C). A modification of the CE30 alloy having the composition balanced to obtain ferrite


P

S

0.04

0.04

Cr 26 30


Fe bal

25.0 0.277 0.14 0.85 2650 > 1.5


____________________ At 212 oF At 600 oF At 1000 oF At 1200 oF

Ni 8 11

70 - 1000 oF 70 - 1200 oF 70 - 1400 oF 70 - 1600 oF

8.5 10.5 12.4 13.5

9.6 9.9 10.2 10.5

Mechanical properties at room temperature

Tensile strength, ksi Yield strength, 0.2% offset, ksi 65.0 Elongation, in 2in., % Brinell hardness (HBW) Charpy, Keyhole, ft. lbs

Representative values As Water quench from Cast 2000 oF to 2050 oF ____________________

Minimum tensile requirements ASTM A743 _____________

95.0

97.0

80.0

45.0 15 190 20

63.0 18 190 7

40.0 10 -

Ratio of Yield and Tesile Strength at Elevated Temperature to Room Temperature Strength Ferrite # 6-8 Ferrite # 40-52 Tensile Yield Tensile Yield Temperature Strength Strength Strength Strength o o C F Ratio Ratio Ratio Ratio 21 50 100 150 200 250 300 350 400 450 500 550 600

70 122 212 302 392 482 572 662 752 842 932 1022 1112

1.000 0.965 0.908 0.859 0.824 0.800 0.781 0.766 0.752 0.731 0.702 0.655 0.580

1.000 0.937 0.835 0.750 0.688 0.650 0.627 0.604 0.583 0.561 0.538 0.511 0.485

1.000 0.965 0.908 0.878 0.863 0.860 0.858 0.853 0.840 0.813 0.745 0.635 0.500

1.000 0.952 0.875 0.802 0.745 0.720 0.711 0.707 0.703 0.695 0.670 0.597 0.487

contents within the range of 5 to 20 percent is being used in oil refinery applications at temperatures around 825°F (440°C). This "controlled ferrite" grade is designated CE30A. This modified grade is more resistant to stress-corrosion cracking by polythionic acid and some chlorides. Castings of the type CE30 alloy have good machining and welding properties. The alloy is magnetic, but not strongly so. Thermal expansion is about 50 percent greater than that of carbon steel or the iron-chromium, CA, CB, and CC types, and is comparable to the CF grades. Heat Treatment Type CE30 castings are used in the as-cast condition for many applications. For maximum corrosion resistance and improved ductility, however, castings should be heated in the range 2000-2050°F (1093-1121°C), and then quenched in water, oil or air to hold as great a portion of the carbides in solution as possible. Holding time at temperature will vary with the thickness of casting sections involved, but should be sufficiently long to heat all sections to a uniform temperature throughout. Applications The following lists of consuming industries, cast parts, and corrosive materials are useful as examples of typical applications where type CE30 alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Chemical Processing, Mining, Oil Refining, Pulp and Paper, Synthetic Fibre Manufacturing. Castings Digester necks and fittings, fittings, circulating systems, fractionating towers, piping, pump bodies and casings, valve bodies and parts. Corrosives Acid mine water, caustic soda, hot nitric acid, hot oil products, organic acids, polythionic acid, sulfite liquors. NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made to the extensive alphabetical lists of corrodents published by many alloy foundries and to corrosion data surveys published by the NACE to determine whether type CE30 is suitable for the particular corrosive involved, and the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. The mechanical and physical property data presented in tabular and graphical form are representative for alloy CE30. These data are neither average nor minimum values, and should not be used for either specification or design purposes. Specification and/or design information may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in CE30 alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Good castability of this alloy permits designs involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allowance for this alloy is 5/16 inch per foot.

Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type CE30 castings can be welded by metal-arc, inert-gas arc, and oxyacetylene gas methods. Metal-arc is most frequently used. Oxyacetylene welding is not advisable because of possible impairment of corrosion resistance caused by carbon pick-up. Preheating is not required, but after welding castings should be quenched from 2000 to 2050°F (1093 to 1121°C) to restore maximum corrosion resistance. Lime coated electrodes of similar composition (AWS E312-15) are recommended for arc welding. Machining Most machining operations can be performed satisfactorily on castings of CE30 alloy. It is important in all cases that the tool be kept continually entering into the metal in order to avoid work-hardening the surface from rubbing or scraping. Slow feeds, deep cuts, and powerful, rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Chips curlers are recommended. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is recommended for high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast ASTM: A743 (CE30). Wrought AISI 312. Also, practices for estimating ferrite content in cast alloys are found in ASTM A799 and A800.

Corrosion Resistant Type CF3 (UNS J92500)

Description Type CF3 is an iron-chromium-nickel alloy of the same family as types CF8 and CF20, but with the carbon content restricted to 0.03 percent maximum. Its corrosion resistance is equal to or better than type CF8 so it is used in similar applications, but particularly in those where post-weld heat treatment is inconvenient or impossible. Damaged ship propellers made of this ductile alloy, for example, can be straightened and repair welded without subsequent heat treatment with no impairment of corrosion resistance. Accordingly, type CF3 is widely used in riverboat service.


P

S

0.04

0.04


Cr 17 21

Ni 8 12

Fe bal

25.0 0.277 0.14 0.85 2650 1.2 to 3.0 Mean coefficient of Linear thermal expansion : in./(in. oF) ______________________

As cast, the alloy has an austenite structure ______________________ containing about 5 to 20 percent ferrite in the form of discontinuous pools, but with At 212 oF 9.2 70 - 212 oF 9.0 virtually no chromium carbides. For this At 1000 oF 12.1 70 - 1000 oF 10.0 reason, the CF-3 grade is suitable for use in many corrodents without the necessity for heat treatment. To be sure of maximum Mechanical properties at room temperature corrosion resistance, however, a solution heat treatment is desirable. If the heat Representative values Minimum treated alloy is later exposed to tensile temperatures around 1200°F (649°C) for Water quench from requirements relatively short times, as would occur in the Above 1950 oF ASTM A743 heat-affected zone of a weld, any chromium _______________ ____________ carbides that are formed would precipitate in the ferrite pools, thereby avoiding any CF3 CF3A CF3 CF3A tendency toward intergranular corrosion in service and eliminating the need for further Tensile strength, ksi 77.0 87.0 70.0 77.0 heat treatment. A "controlled ferrite" grade, Yield strength, 0.2% offset, ksi 36.0 42.0 30.0 35.0 CF3A, has its chemical composition Elongation, in 2in., % 60 50 35 35 balanced so as to obtain the minimum Brinell hardness (HBW) 140 160 ferrite content necessary to ensure meeting Charpy V-notch, ft.lbs 110 100 the high mechanical properties specified for this grade, which has been used extensively in nuclear power plant construction. The CF3A alloy is not considered suitable for service temperatures above about 650°F (343°C). At sub-zero temperatures, impact strength of type CF3 is essentially the same as shown for the CF8 grade. In general, the effect of ferrite on the room-temperature yield and tensile strengths of the type CF3 is the same as that shown for the type CF8. However, because of the lower carbon content of type CF3, the strength values of this type will fall in the lower part, or just below, the "band" of values shown for type CF8. At equal levels of ferrite content, additions of nitrogen result in a significant increase of yield and tensile strengths from room temperature to about 1200°F (649°C). Appropriate ASTM specifications for the CF3 alloy with nitrogen are being prepared.

Castings of the CF3 alloy types have good machining and welding characteristics. Thermal expansion is about 50 percent greater than carbon steel or iron-chromium alloy types CA, CB, and CC. Below about 1600°F (871°C), heat conductivity is 30 to 50 percent less and, above about 1600°F (871°C), the heat conductivities of these materials are nearly equal. Conversely, the electrical resistance of CF3 is five times greater than that of carbon steel and of the iron-chromium alloys below about 1600°F (871°C), but, above this temperature, the electrical resistance of these materials is nearly the same. The alloy is weakly magnetic, with magnetism most pronounced in the CF3A grade. Magnetic permeability of the as-cast alloy may change after heat treatment, depending on the thickness of section and casting configuration. Heat Treatment For maximum corrosion resistance, castings of CF3 alloy should be heated in the range 1900 to 2050°F (1038 to 1121°C), and then quenched in water, oil or air to ensure complete solution of carbides and sigma phase. Holding time at temperature will vary with the thickness of casting sections involved, but should be sufficiently long to heat all sections to a uniform temperature throughout. Applications The following lists of consuming industries, cast parts, and corrosive materials are useful as examples of typical applications where type CF3 alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Beverage, Brewery, Distillery, Food, Heavy Water Manufacturing, Marine, Nuclear Power, Petroleum, Pipe Line, Soap and Detergent. Castings Bowls, discharge cases, impellers, propellers, pump casings, retaining rings, suction manifolds, tubes, valve bodies and parts. Corrosives Brackish water, phosphate solutions, pressurized water at 570°F., sea water, steam. NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made to the extensive alphabetical lists of corrodents published by many alloy foundries and to corrosion data surveys published by the NACE to determine whether type CF3 is suitable for the particular corrosive involved, and the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. The mechanical and physical property data presented in tabular and graphical form are representative for alloy CF3. These data are neither average nor minimum values, and should not be used for either specification or design purposes. Specification and/or design information may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in CF3 alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Good castability of this alloy permits designs involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allowance for this alloy is 5/16 inch per foot.

Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type CF3 castings can be welded by shielded metal-arc, inert-gas arc, and oxyacetylene gas methods. Shielded metal-arc is most frequently used. Oxyacetylene welding is not advisable because of possible impairment of corrosion resistance caused by carbon pick-up. Preheating is not required. Post-weld heat treatment usually is unnecessary for type CF3 castings, but, after welding, quenching from above 1900°F (1038°C) may be desirable for surfaces that will be exposed to severe corrosive attack. Lime coated electrodes of similar composition (AWS E308L-15) are recommended. The welding procedures outlined for alloy CF8 are applicable to alloy CF3. Welding procedures utilizing SMAW, GMAW, and GTAW techniques are described in this section. Machining Most machining operations can be performed satisfactorily on castings of CF3 alloy. It is important in all cases that the tool be kept continually entering into the metal in order to avoid work-hardening the surface. Slow feeds, deep cuts, and powerful, rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Because chips are tough and stringy, chip curler tools are recommended. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is recommended for high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast ASTM: A351 (CF3, CF3A); A451 (CPF3, CPF3A); A743, A744 (CF3). Wrought AISI 304L. Also, practices for estimating ferrite content in cast alloys are found in ASTM A799 and A800.

Corrosion Resistant Type CF3M (UNS J92800)

Description Type CF3M is an iron-chromium-nickelmolybdenum alloy of the same family as type CF8M, but with the carbon content restricted to 0.03 percent maximum. This extra-low carbon limit makes the alloy useful in applications requiring field welding where post-weld heat treatment is inconvenient or impossible. Corrosion resistance of CF3M and general fields of application for the alloy are essentially the same as those of the CF8M grade, and equal to or better than that of the corresponding wrought grade. As normally produced, the CF3M alloy has an austenitic microstructure containing discrete ferrite pools amounting to about 5 percent to 20 percent by volume. When exposed to welding temperatures, these ferrite pools provide a preferred location for precipitation of any carbides that may form, and thus reduce the sensitivity of the alloy by intergranular corrosion caused by grain boundary precipitates. Furthermore, the low carbon content of the alloy limits the formation of significant amounts of chromium carbide in any event, so postweld heat treatment is not required.


P

S

0.04

0.04

Cr 17 21

Physical properties Modulus of elasticity, psi x 106 Density, lb/in3 Sp. Heat, Btu/lb.oF, at 70 oF Electrical resistivity, :S.m, at 70 oF Melting point, approximate oF Magnetic permeability Thermal conductivity Btu/(ft.h. oF) ______________________ At 212 oF At 1000 oF

9.2 12.1

Ni 9 13

Mo 2.0 3.0

Fe bal

28.0 0.28 0.12 0.82 2600 1.5 - 3.0 Mean coefficient of Linear thermal expansion : in./(in. oF) ______________________ -325 - 70 oF -260 - 70 oF -150 - 70 oF 70 - 212 oF 70 - 1000 oF 70 - 1200 oF

8.1 8.2 8.6 9.0 10.0 10.2

Mechanical properties at room temperature Representative values

Minimum

The combination of molybdenum and low tensile carbon content tends to unbalance the Water quench from requirements composition in the direction of high ferrite in above 1900 oF ASTM A743 the alloy microstructure unless the amounts ____________________ _____________ of chromium and nickel are adjusted so as to maintain the ferrite at a low level. Tensile strength, ksi 80.0 90.0 70.0 80.0 Because an increase in ferrite content is Yield strength, 0.2% offset, ksi 38.0 45.0 30.0 30.0 accompanied by an increase in mechanical Elongation, in 2in., % 55 45 30 30 strength, a "controlled ferrite" grade of Brinell hardness (HBW) 150 170 CF3M is made, under the designation of Charpy V-notch, ft lbs 120 100 CF3MA. In this grade, the chemical composition is balanced to obtain a ferrite content sufficiently high to meet minimum yield strength specifications that are about 25 percent higher than for the normal CF3M type. Thermal instability of the microstructure at these high ferrite levels makes the CF3MA alloy generally unsuitable for operation at temperatures above 800°F (427°C). Castings of the CF3M alloy types have good machining and welding characteristics. Thermal expansion is about 50 percent greater than carbon steel or iron-chromium alloy types CA, CB, and CC. Below about 1600°F (871°C), heat conductivity is 30 to 50 percent less and, above about 1600°F (871°C), the heat conductivities of these materials are nearly equal. Conversely, the electrical resistance of CF3M is five

times greater than that of carbon steel and of the iron-chromium alloys below about 1600°F (871°C), but, above this temperature, the electrical resistance of these materials is nearly the same. The alloy is weakly magnetic, with magnetism most pronounced in the CF3MA grade. Magnetic permeability of the as-cast alloy may change after heat treatment, depending on the thickness of section and casting configuration. Heat Treatment For maximum corrosion resistance, castings of CF3M alloy should be heated in the range 1900 to 2050°F (1038 to 1121°C), and then quenched in water, oil or air to ensure complete solution of carbides and sigma phase. Holding time at temperature will vary with the thickness of casting sections involved, but should be sufficiently long to heat all sections to a uniform temperature throughout. Applications The following lists of consuming industries, cast parts, and corrosive materials are useful as examples of typical applications where type CF3M alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Chemical, Copper Mining, Food Processing, Paper Mill, Petroleum, Pipe Line, Power Plant (Fossil Fuel, Hydro, Nuclear), Water Supply. Castings Mixer parts, pump casings and impellers, tubes, valve bodies and parts. Corrosives Acetic acid, calcium carbonate, calcium lactate, potable water, sea water, steam, sulfites. NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made to the extensive alphabetical lists of corrodents published by many alloy foundries and to corrosion data surveys published by the NACE to determine whether type CF3M is suitable for the particular corrosive involved, and the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. The mechanical and physical property data presented in tabular and graphical form are representative for alloy CF3M. These data are neither average nor minimum values, and should not be used for either specification or design purposes. Specification and/or design information may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in CF3M alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Good castability of this alloy permits designs involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allowance for this alloy is 5/16 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot.

Welding Type CF3M castings can be welded by shielded metal-arc, inert-gas arc, and oxyacetylene gas methods. Shielded metal-arc is most frequently used. Oxyacetylene welding is not advisable because of possible impairment of corrosion resistance caused by carbon pick-up. Preheating is not required. Post-weld heat treatment usually is unnecessary for type CF3M castings, but, after welding, quenching from above 1900°F (1038°C) may be desirable for surfaces that will be exposed to severe corrosive attack. Lime coated electrodes of similar composition (AWS E316L-15) are recommended. The welding procedures outlined for alloy CF8M are applicable to alloy CF3M. Welding procedures utilizing SMAW, GMAW, and GTAW techniques are described in this section. Machining Most machining operations can be performed satisfactorily on castings of CF3M alloy. It is important in all cases that the tool be kept continually entering into the metal in order to avoid work-hardening the surface. Slow feeds, deep cuts, and powerful, rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Because chips are tough and stringy, chip curler tools are recommended. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast ASTM: A351 (CF3M, CF3MA); A451 (CPF3M); A743, A744 (CF3M). Wrought AISI 316L. Also, practices for estimating ferrite content in cast alloys are found in ASTM A799 and A800.


Description Type CF8 is an iron-chromium-nickel alloy having good strength and ductility, and excellent resistance to a wide variety of corrodents. The alloy is especially useful in resisting attack by strongly oxidizing media such as boiling nitric acid. Castings of type CF8 alloy have excellent sub-zero properties, retaining high impact strength at temperatures below -400°F (-240°C), as shown in Fig. 2. Corrosion resistance of the cast alloy is equal to or better than the corresponding grade of wrought alloy. As cast, the alloy has a predominantly austenitic structure containing chromium carbides and varying amounts of ferrite distributed throughout the matrix. The carbides must be put into solution by heat treatment to provide maximum corrosion resistance. If the heat treated material is later exposed to temperatures in the range 800 to 1600°F (427 to 871°C), carbides will be reprecipitated; this takes place quite rapidly around 1200°F (649°C). Castings thus "sensitized", as in welding, must be solution heat treated again to restore full corrosion resistance. Type CF8 alloy cannot be hardened by heat treatment, but ductility is improved. The alloy, as normally produced, contains about 10 percent ferrite which takes the form of discrete pools in the microstructure. This ferrite is helpful in avoiding intergranular corrosion in castings exposed to temperatures in the sensitizing range, since carbides are precipitated in the discontinuous ferrite pools rather than in the grain boundaries. It also reduces the tendency for the cracking or microfissuring of welds that is experienced with wholly austenitic alloys. At higher ferrite contents, the strength of the alloy and its resistance to stress corrosion cracking are substantially increased. For this reason, the composition is balanced in the "controlled ferrite", CF8A, grade to obtain considerably higher minimum tensile properties at both room and elevated temperatures up to about 800°F (427°C) than the ordinary CF8 type. The CF8A alloy is not


P

S

0.04

0.04

Cr 18 21

Ni 8 11


bal See Fig. 1 0.28 0.12 0.762 2600 1.0 - 1.3


______________________ At 212 oF At 1000 oF

Fe

-325 - 70 oF -260 - 70 oF -150 - 70 oF 70 - 212 oF 70 - 1000 oF 70 - 1200 oF Mechanical properties at room temperature Representative values Water quench from above 1900 to 2050 oF 9.2 12.1

__________________ CF8

CF8A

8.1 8.2 8.6 9.0 10.0 10.2 Minimum tensile requirements ASTM A743 ____________ CF8

CF8A

Tensile strength, ksi 77.0 95.0 70.0 Yield strength, 0.2% offset, ksi 37.0 45.0 35.0 Elongation, in 2in., % 55 50 30 Brinell hardness (HBW) 140 156 Impact see fig 2 Ratio of Yield and Tesile Strength at Elevated Temperature to Room Temperature Strength

77.0 35.0 35 -

Ferrite # 2-4 TensileYield Temperature Strength o o C F Ratio Ratio

Ferrite # 18-23 TensileYield Strength Ratio Ratio

Ferrite # 33-38 TensileYield Strength Ratio Ratio

21 50 100 150 200 250 300 350 400 450 500 550 600

1.000 0.945 0.865 0.812 0.790 0.787 0.782 0.778 0.772 0.746 0.705 0.640 0.550

1.000 0.945 0.865 0.812 0.790 0.787 0.782 0.778 0.772 0.762 0.735 0.687 0.620

70 122 212 302 392 482 572 662 752 842 932 1022 1112

1.000 0.945 0.865 0.812 0.790 0.787 0.782 0.778 0.772 0.733 0.675 0.588 0.490

1.000 0.911 0.783 0.671 0.590 0.541 0.520 0.509 0.495 0.478 0.458 0.430 0.392

1.000 0.931 0.828 0.738 0.665 0.620 0.605 0.595 0.585 0.570 0.546 0.512 0.462

1.000 0.931 0.828 0.738 0.665 0.620 0.605 0.595 0.585 0.570 0.546 0.512 0.462

Creep - Rupture Properties Estimated Rupture stress, ksi

Estimated Limiting creep stress, ksi

o

100h 1000h

0.01%/h

0.001%/h

1000 1200

38.4 19.4

36.4 9.6

31.6 -

Temperature F

31.3 14.6

considered suitable for service temperatures above about 800°F (427°C). At sub-zero temperatures, alloy compositions balanced to have low ferrite contents have the best impact properties. When non-magnetic castings are needed for an application, compositions can be balanced to be wholly austenitic, but the producer must be notified of this requirement. At equal levels of ferrite content, additions of nitrogen result in a significant increase of yield and tensile strengths from room temperature to about 1200°F (649°C). Appropriate ASTM specifications for the CF8 alloy with nitrogen are being prepared. Castings of the CF8 type have good machining and welding characteristics. Thermal expansion is about 50 percent greater than carbon steel or iron-chromium alloy types CA, CB, and CC. Thermal expansion is about 50 percent greater than that of carbon steel or iron-chromium alloy types CA, CB, and CC. Below about 1600°F (871°C), heat conductivity is 30 to 50 percent less; above about 1600°F (871°C), the thermal conductivity of these materials is nearly equal. Conversely, below about 1600°F (871°C), electrical resistivity is 30 to 50 percent greater than that of carbon steel or the iron-chromium alloys, but above about 1600°F (871°C), the electrical resistivity of these materials is about the same. The alloy varies from non-magnetic to slightly magnetic depending on the composition. Magnetic permeability is not appreciably affected by heat treatment. Heat Treatment For maximum corrosion resistance, castings of CF8 alloy should be heated in the range 1900 to 2050°F (1038 to 1121°C), and then quenched in water, oil or air to ensure complete solution of carbides and sigma phase. Holding time at temperature will vary with the thickness of casting sections involved, but should be sufficiently long to heat all sections to a uniform temperature throughout. Applications The following lists of consuming industries, cast parts, and corrosive materials are useful as examples of typical applications where type CF8 alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Aircraft, Aerospace, Architectural, Beverage and Brewing, Brass Mill, Chemical Processing, Electronic Food Processing, Marine, Military and Naval, Nuclear Power, Oil Refining, Oxygen Manufacturing, Pharmaceutical, Photographic, Plastics, Power Plant, Pulp and Paper, Sewage, Soap Manufacturing, Steel Mill, Synthetic Fibre, Textile. Castings Architectural trim, Army kitchen fittings, autoclaves, blast furnace bushings, catapult parts, computer parts, cooling gauge, cryogenic valves and fittings, dye padder rolls, engine mountings, fan parts, filter press plates and frames, fittings, flanges, guide roller sleeves, hardware, headers, cream pasteurizer, heating coils, Kier and Kier lid, marine fittings, mixing agitators and propellers, mixing kettles, oil burner throat rings, packing rings, periscope tubes, pumps, pump sleeves, radar tubing, redlers, retaining rings, milk coolers, rotary strainers, sanitary fittings (dairy), scrubber castings, shaft sleeves, spray nozzles, stuffing boxes, valve bodies and trim. Corrosives Adipic acid, antibiotics and drugs, bleaching compounds, copper sulfate 190°F (88°C), dye, fatty acids, film developer, fruit juices, gasoline, hot air, hot water, hydrocarbons, hypo, liquid oxygen, mixed H2SO4HNO3, nicotinic acid, nitric acid (hot and concentrated), organic liquids and acids, organic salts, potassium sulfate 1000°F (538°C), sea water, sewage, sodium carbonate, sodium sulfite, steam, sub-zero gases, sulfur dioxide at -20°F (-29°C) 60 psi, 50% sulfuric acid, vinegar, white liquor. NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made

to the extensive alphabetical lists of corrodents published by many alloy foundries and to corrosion data surveys published by the NACE to determine whether type CF8 is suitable for the particular corrosive involved, and the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. The mechanical and physical property data presented in tabular and graphical form are representative for alloy CF8. These data are neither average nor minimum values, and should not be used for either specification or design purposes. Specification and/or design information may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in CF8 alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Good castability of this alloy permits designs involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allowance for this alloy is 5/16 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type CF8 castings can be welded by metal-arc, inert-gas arc, and oxyacetylene gas methods. Metalarc is most frequently used. Oxyacetylene welding is not advisable because of possible impairment of corrosion resistance caused by carbon pick-up. Preheating is not required, but after welding castings should be quenched from 1900 to 2050°F (1038 to 1121°C) to restore maximum corrosion resistance. Lime coated electrodes of similar composition (AWS E308-15) are recommended. Welding procedures utilizing SMAW, GMAW, and GTAW techniques are described in this section. Machining Most machining operations can be performed satisfactorily on castings of CF8 alloy. It is important in all cases that the tool be kept continually entering into the metal in order to avoid work-hardening the surface. Slow feeds, deep cuts, and powerful, rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Because chips are tough and stringy, chip curler tools are recommended. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is recommended for high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast ASTM: A743 (CF8); A351, A743, A744 (CF8, CF8A); A451 (CPF8, CPF8A); SAE 60304; MIL-S-867 (Ships) Class I.

Wrought AISI 304. Also, practices for estimating ferrite content in cast alloys are found in ASTM A799 and A800.

Corrosion Resistant Type CF8C (UNS J92710)

Description Type CF8C is an iron-chromium-nickelcolumbium alloy especially useful for field welding, or for service involving long exposure to elevated temperatures. It is a modification of the CF8 type to which columbium (or columbium plus tantalum) is added to prevent grain boundary precipitation of chromium carbides when the material is heated in the range 8001600°F (427-871°C). The alloy is normally used for the same types of service as type CF8, and provides approximately equivalent corrosion resistance. In the heat treated condition, this alloy has an essentially austenitic structure with small amounts of ferrite (5-20%) distributed throughout the matrix in the form of discontinuous pools. When exposed to temperatures in the range 800-1600°F (427-871°C) for short times (as in welding), or for long times (as in elevated temperature service), precipitation of chromium carbides does not occur if the carbon has been intentionally combined in columbium carbides through prior heat treatment. This circumstance prevents the depletion of chromium along the grain boundary network, and the alloy, therefore, is protected against intergranular corrosion attack. There is no advantage in using this alloy instead of type CF8 if castings can be conveniently solution heat treated after welding, or where there is no danger of exposure to temperatures above 800°F (427°C) in service. Castings of the CF8C type have good machining and excellent welding characteristics. Thermal expansion is about 50 percent greater than carbon steel or iron-chromium alloy types CA, CB, and CC. Below about 1600°F (871°C), heat conductivity is 30 to 50 percent less and, above about 1600°F (871°C), the heat conductivities of these materials are nearly equal. Conversely, the electrical resistance of CF8C is five times greater


P

S

0.04

0.04

Cr 18 21

Ni 9 12

Cb Fe 8xC 1 1.0 bal

Or Cb - Ta 9 x C min., 1.1 max. Physical properties Modulus of elasticity, psi x 106 Density, lb/in3 Sp. Heat, Btu/lb.oF, at 70 oF Electrical resistivity, :S.m, at 70 oF Melting point, approximate oF Magnetic permeability Thermal conductivity Btu/(ft.h. oF)

28 0.28 0.12 0.71 2600 1.2 - 1.8

______________________



70 - 212 oF 70 - 1000 oF

9.3 12.8

9.3 10.3

Mechanical properties at room temperature Representative values Water quench from above 1900 to 2050 oF __________________ Tensile strength, ksi Yield strength, 0.2% offset, ksi Elongation, in 2in., % Brinell hardness (HBW) Charpy, keyhole, ft lbs


77.0 38.0 39 149 30

70.0 30.0 30 -

Ratio of Yield and Tesile Strength at Elevated Temperature to Room Temperature Strength

Temperature o o C F

Tensile Strength Ratio

Yield Strength Ratio

21 50 100 150 200 250 300 350 400 450 500 550 600

1.000 0.924 0.851 0.811 0.788 0.772 0.762 0.752 0.742 0.731 0.713 0.680 0.630

1.000 0.922 0.845 0.791 0.750 0.719 0.692 0.671 0.655 0.639 0.627 0.614 0.601

70 122 212 302 392 482 572 662 752 842 932 1022 1112



o

100h 1000h

0.001%/h

1000 1200

51.6 27.0

43.0 19.5

Temperature F

43.0 19.5

than that of carbon steel and of the iron-chromium alloys below about 1600°F (871°C), but, above this temperature, the electrical resistance of these materials is nearly the same. The alloy is slightly magnetic. Heat Treatment Type CF8C castings can be used as-cast, but they are normally supplied in the heat treated condition. Heat treatment consists of heating in the range 1950-2050°F (1066-1121°C) followed by quenching in water, oil or air to ensure complete solution of any chromium carbides that might have formed in the casting process. A "stabilizing" treatment at 1600 to 1650°F (871 to 899°C) following the solution treatment will cause the preferential precipitation of columbium carbides, and is desirable if castings are for service in the 800 to 1500°F (427 to 816°C) temperature range. Holding times at heat treatment temperatures will vary with the thickness of casting sections involved, but should be sufficiently long to heat all sections to a uniform temperature throughout. Applications The following lists of consuming industries, cast parts, and corrosive materials are useful as examples of typical applications where type CF8C alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Aircraft, Nuclear, Chemical Processing, Marine, Oil Refining, Plastics. Castings Aircraft shroud assemblies, autoclaves, chemical tubing, digesters, engine exhaust fittings, filter press plates, fittings (welding), glands, inlet ring for tank exhaust, jet engine parts, marine fittings, port plates, pump parts, return bends for welding, rotors, tank parts, valve bodies. Corrosives Hydrogen sulfide gas, petroleum products at high temperatures and pressures, plastics, products of combustion of high octane gasoline. NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made to the extensive alphabetical lists of corrodents published by many alloy foundries and to corrosion data surveys published by the NACE to determine whether type CF8C is suitable for the particular corrosive involved, and the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. The mechanical and physical property data presented in tabular and graphical form are representative for alloy CF8C. These data are neither average nor minimum values, and should not be used for either specification or design purposes. Specification and/or design information may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in CF8C alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Good castability of this alloy permits designs involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allowance for this alloy is 11/32 inch per foot.

Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type CF8C castings can be welded by metal-arc, inert-gas arc, and oxyacetylene gas methods. Metal-arc is most frequently used. Oxyacetylene welding is not advisable because of possible impairment of corrosion resistance caused by carbon pick-up. Preheating is not required, but after welding castings may be quenched from 1950 to 2050°F (1066 to 1121°C) to restore maximum corrosion resistance. Postweld heat treatment usually is not necessary. Lime coated electrodes of similar composition (AWS E347-15) are recommended. Machining Most machining operations can be performed satisfactorily on castings of CF8C alloy. It is important in all cases that the tool be kept continually entering into the metal in order to avoid work-hardening the surface. Slow feeds, deep cuts, and powerful, rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. This alloy is somewhat easier to machine than the CF8 type, but the chips are tough and chip curler tools are recommended. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is recommended for high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast ASTM: A351, A743, A744 (CF8C); A451 (CPF8C); AMS 5363B; SAE 60347; MIL-S-867 (Ships) Class II. Wrought AISI 347. Also, practices for estimating ferrite content in cast alloys are found in ASTM A799 and A800.

Effect of Ferrite Content on 0.2% Yield--CF8C #1

Lower limit

Upper limit

% Ferrite

ksi

% Ferrite

ksi

-

-

0

36.875

5

30.625

5

40.313

10

33.750

10

43.438

15

36.563

15

46.250

2

38.438

20

48.125

25

40.000

25

49.375

30

41.563

30

50.313

Effect of Ferrite Content on Tensile Strength of CF8C #2

Lower limit

Upper limit

% Ferrite

ksi

% Ferrite

ksi

0

60.313

0

72.344

5

71.563

5

77.500

10

75.938

10

81.563

15

79.375

15

85.000

20

82.188

20

87.344

25

84.063

25

88.907

30

85.782

30

90.000

Corrosion Resistant Type CF8M (UNS J92900) and CF12M

Description Type CF8M is an iron-chromium-nickelmolybdenum alloy differing only in carbon content. It is a modification of the CF8 type to which molybdenum is added to enhance general corrosion resistance and to provide greater strength at elevated temperatures. The alloy has good resistance to reducing corrosive media, and is substantially more resistant to pitting corrosion than the CF8 grade when exposed to chlorides as in sea water. Although not quite so resistant to strongly oxidizing corrodents such as boiling nitric acid, the molybdenum containing alloy is more stably passive than the CF8 type under weakly oxidizing conditions. Corrosion resistance of the cast alloy is approximately equal to, or better than, corresponding types of wrought alloys. In the heat treated condition, this alloy has a predominantly austenitic structure with small amounts of ferrite (15-25%) distributed throughout the matrix in the form of discontinuous pools. When heated in the range 800 to 1600°F (427 to 871°C) (such as would occur in a welding operation), these pools provide a preferred location for carbides to precipitate, thus tending to reduce susceptibility of the alloy to intergranular corrosion caused by precipitation of carbides at austenite grain boundaries. The amount of ferrite present decreases as carbon content of the alloy is increased. By suitable balancing of the compositions, the alloy can be made wholly austenitic and non-magnetic. At operating temperatures of 1200°F (649°C) or higher, ferrite may transform to the brittle sigma phase. Maximum corrosion resistance, however, is associated with low carbon and high chromium contents, and for this reason, the partially ferritic CF8M type is usually employed at operating temperatures below 1000°F (538°C). Castings of the CF8M type have good machining and welding characteristics. Thermal expansion is about 50 percent

Chemical composition - % C Mn CF8M min. max. 0.08 1.50

2.00

CF12M min. max. 0.12

2.00

1

1.50

Si 1

P

S 0.04

Cr 18 21

Ni 8 11

Mo 2.0 3.0

0.04 0.04

0.04

18 21

8 11

2.0 3.0

Fe bal bal

Si limited to 1.50 max for CF8M in ASTM A351


28 0.28 0.12 0.82 2550 1.5 - 2.5

______________________



70 - 212 oF 70 - 1000 oF

9.2 12.1

8.9 9.7

Mechanical properties at room temperature Representative values Water quench from above 1950 to 2100 oF2 __________________ Tensile strength, ksi Yield strength, 0.2% offset, ksi Elongation, in 2in., % Brinell hardness (HBW) Charpy, keyhole, ft lbs


80.0 42.0 50 156 - 170 See fig 1

70.0 30.0 30 -

2

Type CF12M quenched from above 2000 oF Applies to type CF8M only; CF12M not covered by ASTM A743

3

Ratio of Yield and Tesile Strength at Elevated Temperature to Room Temperature Strength

Temperature o o C F

Ferrite # 16-20 Ferrite # 3-10 Tensile Yield Tensile Strength Strength Strength Ratio Ratio Ratio

Yield Strength Ratio

21 50 100 150 200 250 300 350 400 450 500 550 600

1.000 0.932 0.867 0.831 0.812 0.809 0.807 0.802 0.797 0.785 0.765 0.728 0.663

1.000 0.930 0.839 0.773 0.720 0.680 0.651 0.628 0.607 0.586 0.568 0.548 0.528

70 122 212 302 392 482 572 662 752 842 932 1022 1112

1.000 0.895 0.772 0.692 0.639 0.600 0.571 0.547 0.527 0.510 0.491 0.475 0.460

1.000 0.968 0.920 0.880 0.855 0.849 0.845 0.842 0.839 0.830 0.795 0.740 0.663



o

100h 1000h

0.01%/h

0.001%/h

1000 1200

47.2 24.6

45.2 13.0

41.2 -

Temperature F

42.5 18.2

greater than carbon steel or iron-chromium alloy types CA, CB, and CC. Below about 1600°F (871°C), heat conductivity is 30 to 50 percent less and, above about 1600°F (871°C), the heat conductivities of these materials are nearly equal. Conversely, the electrical resistance of CF8M is five times greater than that of carbon steel and of the iron-chromium alloys below about 1600°F (871°C), but, above this temperature, the electrical resistance of these materials is nearly the same. The alloys are ductile and are the strongest of the 19 Cr, 9 Ni types. Heat Treatment For maximum corrosion resistance, castings of CF8M and CF12M alloys should be heated in the range 1950 to 2100°F (1066 to 1149°C) and then quenched in water, oil or air to ensure complete solution of carbides and sigma phase. Holding time at temperature will vary with the thickness of casting sections involved, but should be sufficiently long to heat all sections to a uniform temperature throughout. The low side of the range may be used for type CF8M castings. Applications The following lists of consuming industries, cast parts, and corrosive materials are useful as examples of typical applications where type CF8M alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Aircraft, A.E.C., Chemical Processing, Electronic, Fertilizer, Food Processing, Guided Missile, Marine, Mining, Oil Refining, Pharmaceutical, Photographic, Plastics, Power Plant, Soap, Synthetic Fibre, Synthetic Rubber, Textile. Castings Agitators, blast plates, centrifuges, evaporator parts, filter press plates and frames, fittings, jet engine components, mixing propellers, pump parts, radar masts, rolls, spool heads, spray nozzles, high pressure steam valves, valve bodies and parts. Corrosives Acetones, acetic acid, alkaline carbonate, amyl-acetate, ash-laden water, benzene, hexachloride, black liquor, bleaching compounds, blood plasma, chloride solutions, copper refining electrolyte, crude methacrylic acid, dyes (hot), fatty acids, high sulfur mine waters, hydrocarbon vapors, hydrogen peroxide, phosphoric acid [to 85%, to 200°F (93°C)], riboflavin syrup, salt water, slurries (phosphoric plus sulfuric and hydrofluoric acids), steam at high pressures and temperatures, sulfate and sulfite liquors, sulfuric acid (dilute or concentrated, oleum), sulfurous acid, vinyl alcohol. NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made to the extensive alphabetical lists of corrodents published by many alloy foundries and to corrosion data surveys published by the NACE to determine whether type CF8M is suitable for the particular corrosive involved, and the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. The mechanical and physical property data presented in tabular and graphical form are representative for alloy CF8M. These data are neither average nor minimum values, and should not be used for either specification or design purposes. Specification and/or design information may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in CF8M alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Good castability of this alloy permits designs

involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allowance for this alloy is 5/16 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type CF8M castings can be welded by metal-arc, inert-gas arc, and oxyacetylene gas methods. Metal-arc is most frequently used. Oxyacetylene welding is not advisable because of possible impairment of corrosion resistance caused by carbon pick-up. Preheating is not required, but after welding castings should be quenched from 1950 to 2100°F (1066 to 1149°C) to restore maximum corrosion resistance. Postweld heat treatment may be omitted provided castings will not be exposed to highly corrosive solutions. Lime coated electrodes of similar composition (AWS E316-15) are recommended. Welding procedures utilizing SMAW, GMAW, and GTAW techniques are described in this section. Machining Most machining operations can be performed satisfactorily on castings of CF8M and CF12M alloys. It is important in all cases that the tool be kept continually entering into the metal in order to avoid workhardening the surface. Slow feeds, deep cuts, and powerful, rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Because chips are tough and stringy, chip curler tools are recommended. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast ASTM: A351, A743, A744 (CF8M); A451 (CPF8M); SAE 60316; MIL-S-867 (Ships) Class III. Wrought AISI 316. Also, practices for estimating ferrite content in cast alloys are found in ASTM A799 and A800.

Corrosion Resistant Type CF16F (UNS J92701)

Description Type CF16F is an iron-chromium-nickel alloy similar to types CF8 and CF20, to which small amounts of selenium, either with or without molybdenum, and phosphorus have been added to improve machinability. Corrosion resistance of this alloy is somewhat inferior to the CF20 type, but it is adequate for many purposes. As cast, this alloy has an austenitic structure containing chromium carbides and varying amounts of ferrite (0-15%) distributed throughout the matrix. The carbides must be put into solution by heat treatment to provide maximum corrosion resistance. Complex selenides, which are present in both the as-cast and heat treated material, contribute a freemachining quality to these alloys by serving as chip breakers. If the heat treated material is later exposed to temperatures in the range 800 to 1600°F (427 to 871°C), carbides will be reprecipitated; this takes place quite rapidly around 1200°F (649°C). Castings thus "sensitized", as in welding, must be solution heat treated again to restore full corrosion resistance. Type CF16F cannot be hardened by heat treatment, but ductility is improved. Castings of the CF16F type have excellent machining and good welding characteristics. Thermal expansion and other physical properties are similar to the CF8 grade.


P

S

0.04

0.04

Cr 18 21

Ni 9 12


Mo 1.50

Fe bal

28 0.28 0.12 0.72 2550 1.0 - 2.0

______________________



70 - 212 oF 70 - 1000 oF

9.4 12.1

Se 0.20 0.35

9.0 9.9

Mechanical properties at room temperature Representative values Water quench from above 2000 oF __________________ Tensile strength, ksi Yield strength, 0.2% offset, ksi Elongation, in 2in., % Brinell hardness (HBW) Charpy, keyhole, ft lbs

77.0 40.0 52 150 75

Minimum tensile requirements ASTM A743 _____________ 70.0 30.0 25 -

Heat Treatment For maximum corrosion resistance, castings of CF16F alloy should be heated in the range 1950 to 2050°F (1066 to 1121°C) and then quenched in water, oil or air to ensure complete solution of carbides. Holding time at temperature will vary with the thickness of casting sections involved, but should be sufficiently long to heat all sections to a uniform temperature throughout. Applications The following lists of consuming industries, cast parts, and corrosive materials are useful as examples of typical applications where type CF16F alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses.

Industries Architectural, Chemical Processing, Explosives Manufacturing, Food and Dairy, Marine, Oil Refinery, Pharmaceutical, Power Plants, Pulp and Paper, Textile. Castings Bearings, bushings, fittings, flanges, machinery parts, pump casings, valves. Corrosives Atmosphere, bleaching compounds, caustic salts, food products, hydrocarbon vapors, sulfite liquor, sulfurous acid. NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made to the extensive alphabetical lists of corrodents published by many alloy foundries and to corrosion data surveys published by the NACE to determine whether type CF16F is generally recommended for the particular corrosive involved, and the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. The mechanical and physical property data presented in tabular and graphical form are representative for alloy CF16F. These data are neither average nor minimum values, and should not be used for either specification or design purposes. Specification and/or design information may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in CF16F alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Good castability of this alloy permits designs involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allowance for this alloy is 5/16 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type CF16F castings can be welded by metal-arc, inert-gas arc, and oxyacetylene gas methods. Metal-arc is most frequently used. Oxyacetylene welding is not advisable because of possible impairment of corrosion resistance caused by carbon pick-up. Preheating is not required, but after welding castings should be quenched from 2000 to 2100°F (1093 to 1149°C) to restore maximum corrosion resistance. Lime coated electrodes of similar composition (AWS E308-15 or E308L-15) are recommended. The welding procedures outlined for alloy CF8 are applicable to alloy CF16F. Welding procedures utilizing SMAW, GMAW, and GTAW techniques are described in this section. Machining Most machining operations can be performed readily on castings of CF16F alloy. It is important in all cases that the tool be kept continually entering into the metal in order to avoid work-hardening the surface. Slow feeds, deep cuts, and powerful, rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Chips tend to free themselves more readily from the tool and break more easily than is the case with other CF grades. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur

without a fatty base oil is recommended for high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast ASTM: A743 (CF16F); SAE 60303 and 60303a. Wrought AISI 303. Also, practices for estimating ferrite content in cast alloys are found in ASTM A799 and A800.


Description Type CF20 is an iron-chromium-nickel alloy containing a maximum of 0.20 percent carbon. The alloy serves satisfactorily in many types of oxidizing corrosion service where its superior ductility and impact strength make it more useful than the ironchromium type CB30. Providing considerably better corrosion resistance than the iron-chromium type CA15, the CF20 alloy is, in general, similar to the low carbon CF8 grade except that it is used for less severe operating conditions. As cast, the alloy has an austenitic structure containing chromium carbides. The carbides must be put into solution by heat treatment to provide maximum corrosion resistance. If the heat treated material is later exposed to temperatures in the range 800 to 1600°F (427 to 871°C), carbides will be reprecipitated; this takes place quite rapidly around 1200°F (649°C). Castings thus "sensitized", as in welding, must be solution heat treated again to restore full corrosion resistance. Type CF20 alloy cannot be hardened by heat treatment. Castings of the CF20 type have good machining and welding characteristics. Thermal expansion is about 50 percent greater than carbon steel or iron-chromium alloy types CA, CB, and CC.


P

S

0.04

0.04

Cr 18 21

Ni 8 11


Fe bal

28 0.28 0.12 0.779 2575 1.01

______________________



70 - 212 oF 70 - 1000 oF

9.2 12.1

9.6 10.4


77.0 36.0 50 163 60


Below about 1600°F (871°C), heat conductivity is 30 to 50 percent less and, above about 1600°F (871°C), the heat conductivities of these materials are nearly equal. Conversely, the electrical resistance of CF-20 is five times greater than that of carbon steel and of the iron-chromium alloys below about 1600°F (871°C), but, above this temperature, the electrical resistance of these materials is nearly the same. In contrast to the CF8 type, the higher carbon content of the CF20 alloy makes it virtually non-magnetic. Heat Treatment For maximum corrosion resistance, castings of CF20 alloy should be heated in the range 2000 to 2100°F (1093 to 1149°C) and then quenched in water, oil or air to ensure complete solution of carbides. Holding time at temperature will vary with the thickness of casting sections involved, but should be sufficiently long to heat all sections to a uniform temperature throughout.

Applications The following lists of consuming industries, cast parts, and corrosive materials are useful as examples of typical applications where type CF20 alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Architectural, Chemical Processing, Explosives Manufacturing, Food and Dairy, Marine, Oil Refinery, Pharmaceutical, Power Plants, Pulp and Paper, Textile. Castings Circuit breaker parts, cylinder liners and sleeves, pumps, return bends, rolls, street markers, valve bodies and parts. Corrosives Atmosphere, bleaching compounds, caustic salts, food products, hydrocarbon vapors, sulfite liquor, sulfurous acid. NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made to the extensive alphabetical lists of corrodents published by many alloy foundries and to corrosion data surveys published by the NACE to determine whether type CF20 is suitable for the particular corrosive involved, and the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. The mechanical and physical property data presented in tabular and graphical form are representative for alloy CF20. These data are neither average nor minimum values, and should not be used for either specification or design purposes. Specification and/or design information may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in CF20 alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Good castability of this alloy permits designs involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allowance for this alloy is 11/16 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type CF20 castings can be welded by metal-arc, inert-gas arc, and oxyacetylene gas methods. Metal-arc is most frequently used. Oxyacetylene welding is not advisable because of possible impairment of corrosion resistance caused by carbon pick-up. Preheating is not required, but after welding castings should be quenched from 2000 to 2100°F (1093 to 1149°C) to restore maximum corrosion resistance. Lime coated electrodes of similar composition (AWS E308-15) are recommended. The welding procedures outlined for alloy CF8 are applicable to alloy CF20. Welding procedures utilizing SMAW, GMAW, and GTAW techniques are described in this section. Machining Most machining operations can be performed satisfactorily on castings of CF20 alloy. It is important in all cases that the tool be kept continually entering into the metal in order to avoid work-hardening the surface. Slow feeds, deep cuts, and powerful, rigid machines are necessary for best results. Work should be firmly

mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Because chips are tough and stringy, chip curler tools are recommended. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is recommended for high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast ASTM: A743 (CF20); SAE 60302. Wrought AISI 302.

Corrosion Resistant Type CG8M (UNS J93000)

Description Type CG8M is an iron-chromium-nickelmolybdenum alloy with excellent resistance to corrosion by reducing media. Except for its higher molybdenum content, the CG8M alloy is similar to the widely used CF8M grade. The addition of approximately one percent more molybdenum, however, increases the resistance of the alloy to sulfurous and sulfuric acid solutions, and to the pitting action of halogen compounds. Thus, it is preferred to CF8M in applications where improved resistance to such corrodents is required. It is not suitable for use in nitric acid or other strongly oxidizing environments. After heat treatment, the normal microstructure of the alloy consists of an austenitic matrix in which 15 to 35 percent of ferrite is distributed in the form of discontinuous pools. This ferrite content gives the alloy considerable resistance to stress corrosion cracking, and high strength at room and elevated temperatures. It should be noted that long exposure to temperatures above 1200°F (649°C) may cause the alloy to become embrittled from transformation of some ferrite to the sigma phase. Castings of the CG8M alloy type have good machining and welding characteristics. Thermal expansion is about 50 percent greater than carbon steel or the iron-chromium alloy types CA, CB, and CC.


P

S

0.04

0.04

Cr 18 21

Ni 9 13


Mo 3.0 4.0

bal

28 0.28 0.12 0.82 2550 1.5 - 3.0

______________________



70 - 212 oF 70 - 1000 oF

9.4 12.1

Fe

8.9 9.7

Mechanical properties at room temperature Representative values Water quench from above 1900 oF __________________ Tensile strength, ksi Yield strength, 0.2% offset, ksi Elongation, in 2in., % Brinell hardness (HBW) Charpy V-notch, ft lbs 80


82.5 44.0 45 176

75.0 35.0 30 -

Below about 1600°F (871°C), heat conductivity is about 30 percent less and, above about 1600°F (871°C), the heat conductivities of these materials are nearly equal. Conversely, the electrical resistance of CG8M is five times greater than that of carbon steel and of the iron-chromium alloys below about 1600°F (871°C), but, above this temperature, the electrical resistance of these materials is nearly the same. The alloy is ductile and retains good strength at temperatures in the 600 to 800°F (316 to 427°C) range. Heat Treatment For maximum corrosion resistance, castings of CG8M alloy should be heated in the range 1950 to 2050°F (1065 to 1121°C) and then quenched in water, oil or air to ensure complete solution of carbides and sigma phase. Holding time at temperature will vary with the thickness of casting sections involved, but should be sufficiently

long to heat all sections to a uniform temperature throughout. Applications The following lists of consuming industries, cast parts, and corrosive materials are useful as examples of typical applications where type CG8M alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Heavy Water Manufacturing, Nuclear, Petroleum, Pipe Line, Power, Pulp and Paper, Printing, Textile. Castings Dyeing equipment, flow meter components, propellers, pump parts, valve bodies and parts. Corrosives Dye solutions, ink, Mississippi River water, sulfite liquor. NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made to the extensive alphabetical lists of corrodents published by many alloy foundries and to corrosion data surveys published by the NACE to determine whether type CG8M is suitable for the particular corrosive involved, and the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. The mechanical and physical property data presented in tabular and graphical form are representative for alloy CG8M. These data are neither average nor minimum values, and should not be used for either specification or design purposes. Specification and/or design information may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in CG-8M alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Good castability of this alloy permits designs involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allowance for this alloy is 5/16 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type CG-8M castings can be welded by metal-arc, inert-gas arc, and oxyacetylene gas methods. Shielded metal-arc is most frequently used. Oxyacetylene welding is not advisable because of possible impairment of corrosion resistance caused by carbon pick-up. Preheating is not required, but after welding castings should be quenched from above 1950°F (1065°C) to restore maximum corrosion resistance. Lime coated electrodes of similar composition (AWS E317-15) are recommended. The welding procedures outlined for alloy CF8M are applicable to alloy CG8M. Welding procedures utilizing SMAW, GMAW, and GTAW techniques are described in this section. Machining Most machining operations can be performed satisfactorily on castings of CG8M alloy. It is important in all cases that the tool be kept continually entering into the metal in order to avoid work-hardening the surface. Slow feeds, deep cuts, and powerful, rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel

and carbide tools may be used successfully. Because chips are tough and stringy, chip curler tools are recommended. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is recommended for high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast ASTM: A743, A744 (CG8M). Wrought AISI 317.

Corrosion Resistant Type CH20 (UNS J93402)

Description Type CH20 is an iron-chromium-nickel alloy similar to type CE30, but with somewhat higher nickel and lower chromium and carbon contents. Mechanical properties of this alloy lie between those of the CE30 and the CF8 types: it is more ductile than CE30 but not as strong; stronger than CF8 but not as ductile. The higher nickel and chromium contents impart to this alloy considerably better resistance to certain corrosive media than is available with the CF8 type. It is used most frequently in applications involving contact with hot dilute sulfuric acid. This grade is sometimes made with carbon limited to 0.10 percent maximum (CH10), and with a molybdenum addition (CH10M) to provide further improvement over the resistance of the CF8 and CF8M grades. As cast, the alloy has an essentially austenitic structure containing chromium carbides and small amounts of ferrite distributed throughout the matrix. The carbides must be put into solution by heat treatment to provide maximum corrosion resistance. If the heat treated material is later exposed to temperatures in the range 800 to 1600°F (427 to 871°C), carbides will be reprecipitated. Type CH alloys are not hardened by heat treatment, but ductility and strength are improved.


P

S

0.04

0.04

Cr 22 26

Ni 12 15


Fe bal

28 0.279 0.12 0.84 2600 1.71

______________________


At 212 oF At 600 oF At 1000 oF

70 - 212 oF 70 - 600 oF 70 - 1000 oF

8.2 10.1 12.0

8.6 8.7 9.5


88.0 50.0 38 190 30


Castings of the type CH20 alloy have fair machinability and good weldability. Thermal expansion is about 50 percent greater than carbon steel, but slightly less than the CF alloy types. Below about 1600°F (871°C), the heat conductivity is lower than for the CF grades, and the electrical resistance is about 10 percent higher; above about 1600°F (871°C), the thermal and electrical properties of these materials are nearly equal. The alloy is slightly magnetic. Heat Treatment For maximum corrosion resistance, castings of CH20 alloy should be heated in the range 2000 to 2100°F (1093

to 1149°C) and then quenched in water, oil or air to ensure complete solution of carbides. Holding time at temperature will vary with the thickness of casting sections involved, but should be sufficiently long to heat all sections to a uniform temperature throughout. Applications The following lists of consuming industries, cast parts, and corrosive materials are useful as examples of typical applications where type CH20 alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Chemical Processing, Power Plant, Pulp and Paper. Castings Digester fittings, pumps and parts, roasting equipment, valves, water strainers. Corrosives Sulfite liquor, sulfuric acid (hot, dilute). NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made to the extensive alphabetical lists of corrodents published by many alloy foundries and to corrosion data surveys published by the NACE to determine whether type CH20 is suitable for the particular corrosive involved, and the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. The mechanical and physical property data presented in tabular and graphical form are representative for alloy CH20. These data are neither average nor minimum values, and should not be used for either specification or design purposes. Specification and/or design information may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in CH20 alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Good castability of this alloy permits designs involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allowance for this alloy is 5/16 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type CH20 castings can be welded by metal-arc, inert-gas arc, and oxyacetylene gas methods. Metal-arc is most frequently used. Oxyacetylene welding is not advisable because of possible impairment of corrosion resistance caused by carbon pick-up. Preheating is not required, but after welding castings should be quenched from 2000 to 2100°F (1093 to 1149°C) to restore maximum corrosion resistance. Postweld heat treatment may be omitted provided castings will not be exposed to highly corrosive solutions. Lime coated electrodes of similar composition (AWS E309-15) are recommended. Machining Most machining operations can be performed satisfactorily on castings of CH20 alloy. It is important in all cases that the tool be kept continually entering into the metal in order to avoid work-hardening the surface. Slow feeds, deep cuts, and powerful, rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Because chips are tough and stringy, chip curler tools are

recommended. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is recommended for high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast ASTM: A351, A743 (CH20); A451 (CPH20); SAE 60309. Wrought AISI 309.

Corrosion Resistant Type CK3MCuN (UNS J93254) and CN3MN (UNS J94651)

Description Types CK3MCuN and CN3MN8 are iron-chromium-nickel-molybdenum alloys. They are commonly referred to as the “6% Mo Superaustenitics”. They have slightly higher strength and ductility levels than CF8M. They have excellent resistance to a wide variety of corrosive media. The primary corrosion environments for these alloys are chloride containing media. The critical crevice temperature is much higher than the 19 chromium, 10 nickel, molybdenum bearing alloys. It has been reported that the toughness of the wrought forms of these alloys compares favorably with the “300" series alloys.

Chemical composition - % C CK3MCuN

CN3MN

Mn

Si

P

min. max. 0.025 1.20

1

min. max. 0.03

1

2

Ni

Mo

Cu

N

19.5 0.045 0.010 20.5

17.5 19.5

6 7

0.5 1

0.18 0.24

20 0.040 0.010 22

23.5 25.5

6 7

-

0.18 0.26

Physical properties Modulus of elasticity, psi x 106 Density, lb/in3 Sp. Heat, Btu/lb.oF, at 70 oF Electrical resistivity, :S.m, at 70 oF Melting point, approximate oF

S

Cr

0.291 0.11 0.89 2450

Thermal conductivity Btu/(ft.h. oF)

68- 212 oF

6.8

Mechanical properties at room temperature Minimum tensile requirements ASTM A743 _______________________________

Tensile strength, ksi Yield strength, 0.2% offset, ksi Elongation, in 2in., %

CK3MCuN

CN3MN

80 38 35

80 38 35

As cast, the alloy has a predominantly austenitic structure containing chromium carbides, sigma and varying amounts of ferrite distributed throughout the matrix. The carbides and sigma`must be put into solution by heat treatment to provide maximum corrosion resistance. If the heat treated material is later exposed to temperatures in the range 800 to 1600°F (427 to 871°C), carbides will be reprecipitated; this takes place quite rapidly around 1200°F (649°C). Sigma can also form above 1000°F (538°C) these temperatures. Castings thus "sensitized",

as in welding, must be solution heat treated again to restore full corrosion resistance. These alloys cannot be hardened by heat treatment. The alloys, as normally produced, are fully austenitic although small pools of ferrite have been observed in CK3MCuN in the microstructure. Heat Treatment ASTM A744 specifies a minimum solution heat treatment temperature of 2100°Ffollowed by quenching in water or rapid cooling by other means. It has been observed that the higher the solution treatment temperature the higher the Critical Pitting Temperature and the lower the intergranular corrosion rate. This treatment should ensure the complete solution of carbides and sigma phase. Holding time at temperature will vary with the thickness of casting sections involved, but should be sufficiently long to heat all sections to a uniform temperature throughout. Applications The following lists of consuming industries, cast parts, and corrosive materials are useful as examples of typical applications where the “6 Mo superaustenitc” grades have been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Aerospace, Beverage, Biopharmaceutical, Brewing, Brine Concentrators, Chemical Processing, Desalination, Distillation, Flue Gas Desulfurization, Food Processing, Heating Furnaces, Marine, Military and Naval, Nuclear Power, Oil and Gas Production, Offshore Platforms, Pharmaceutical, Pulp and Paper, Seawater Handling Equipment, Semi-conductor, Steam Surface Condensers. Castings Cryogenic valves and fittings, fittings, flanges, headers, marine fittings, mixing agitators and propellers, pumps, pump sleeves, milk coolers, rotary strainers, sanitary fittings (dairy), scrubber castings, shaft sleeves, spray nozzles, stuffing boxes, valve bodies and trim. Corrosives Acetic acid, antibiotics and drugs, bleaching compounds, formic acid, fruit juices, hot air, hot water, hydrocarbons, hydrochloric acid, organic liquids and acids, nitric acid, organic salts, oxalic acid, phosphoric acid, sea water, sewage, sodium bisulfate, sodium hydroxide, steam, sulfamic acid, 10% sulfuric acid, vinegar, white liquor. NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made to the extensive alphabetical lists of corrodents published by many alloy foundries and to corrosion data surveys published by the NACE to determine whether “6% Mo superaustentic” grades are suitable for the particular corrosive involved, and the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. The mechanical and physical property data presented in tabular form are representative for alloys CK3MCuN and CN3MN. These data are neither average nor minimum values, and should not be used for either specification or design purposes. Specification and/or design information may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in these alloys. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allowance for this alloy is 5/16 inch per foot.

Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type CK3MCuN and CN3MN castings can be welded by metal-arc, inert-gas arc, and oxyacetylene gas methods. Metal-arc is most frequently used. Oxyacetylene welding is not advisable because of possible impairment of corrosion resistance caused by carbon pick-up. Preheating is not required, but after welding castings should be quenched from a minimum of 2100°F (1121°C) to restore maximum corrosion resistance. Machining Most machining operations can be performed satisfactorily on castings of CK3MCuN and CN3MN alloys. It is important in all cases that the tool be kept continually entering into the metal in order to avoid workhardening the surface. Slow feeds, deep cuts, and powerful, rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Because chips are tough and stringy, chip curler tools are recommended. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is recommended for high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy Cast ASTM: A743, A744 (CK3MCuN, CN3MN) Wrought 254 SMO (UNS S31254), AL6XN (UNS N08367)

Corrosion Resistant Type CK20 (UNS J94202)

Description Type CK20 is an iron-chromium-nickel alloy containing slightly more chromium and considerably more nickel than the CH20 grade. It is used for special service conditions at high temperatures, handling about the same corrodents as CH20. The alloy provides good resistance to dilute sulfuric acid and resists many corrodents more effectively than the CF8 type. Because of its high alloy content, it is usually employed only where specific requirements warrant the cost. As cast, the alloy has an austenitic structure containing chromium carbides distributed throughout the matrix. The carbides must be put into solution by heat treatment to provide maximum corrosion resistance. If the heat treated material is later exposed to temperatures in the range 800 to 1600°F (427 to 871°C), carbides will be reprecipitated. Type CK alloy is not hardened by heat treatment, but ductility and strength are improved. Castings of the type CK20 alloy have good machining and welding characteristics. Thermal expansion is about 50 percent greater than carbon steel, but slightly less than the CF alloy types. Below about 1600°F (871°C), the heat conductivity is lower than for the CF grades, and the electrical resistance is about 15 percent higher than that of CF8; above about 1600°F (871°C), the thermal and electrical properties of these materials are nearly equal.

Chemical composition - % C Mn Si P min. max. 0.20 2.001 2.001 0.04

S 0.04

Cr 23 27

Ni 19 22

Fe bal

1

Limits in ASTM A743. Limits in A351 are: Mn 1.50 max., Si 1.75 max.


29 0.28 0.12 0.9 2600 1.02

______________________


At 212 oF At 600 oF At 1000 oF

70 - 212 oF 70 - 600 oF 70 - 1000 oF

7.9 9.8 11.8

8.3 8.9 9.4

Mechanical properties at room temperature Representative values Water quench from above 2100 oF __________________

Tensile strength, ksi 76.0 Yield strength, 0.2% offset, ksi 38.0 Elongation, in 2in., % 37 Brinell hardness (HBW) 190 Charpy V-notch, ft lbs See Fig. 1

Minimum tensile requirements ASTM A743 ____________ _ 65.0 28.0 30 -

The alloy is virtually non-magnetic. Heat Treatment For maximum corrosion resistance, castings of CK20 alloy should be heated in the range 2000 to 2150°F (1093 to 1177°C) and then quenched in water, oil or air to ensure complete solution of carbides. Holding time at temperature will vary with the thickness of casting sections involved, but should be sufficiently long to heat all sections to a uniform temperature throughout.

Applications The following lists of consuming industries, cast parts, and corrosive materials are useful as examples of typical applications where type CK20 alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Aircraft, Chemical Processing, Oil Refining, Pulp and Paper. Castings Digesters, filter press plates and frames, fittings, jet engine parts, mixing kettles, pumps, return bends, tar still fittings, valves. Corrosives Hot oil products around 1200°F (649°C), sulfite liquor, sulfuric acid (dilute). NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made to the extensive alphabetical lists of corrodents published by many alloy foundries and to corrosion data surveys published by the NACE to determine whether type CK20 is suitable for the particular corrosive involved, and the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. The mechanical and physical property data presented in tabular and graphical form are representative for alloy CK20. These data are neither average nor minimum values, and should not be used for either specification or design purposes. Specification and/or design information may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in CK20 alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Good castability of this alloy permits designs involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allowance for this alloy is 5/16 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type CK20 castings can be welded by metal-arc, inert-gas arc, and oxyacetylene gas methods. Metal-arc is most frequently used. Oxyacetylene welding is not advisable because of possible impairment of corrosion resistance caused by carbon pick-up. Preheating is not required, but after welding castings should be quenched from 2000 to 2150°F (1093 to 1177°C) to restore maximum corrosion resistance. Postweld heat treatment may be omitted provided castings will not be exposed to highly corrosive solutions. Lime coated electrodes of similar composition (AWS E310-15) are recommended. Welding procedures utilizing SMAW, and GTAW techniques are described in this section. Machining Most machining operations can be performed satisfactorily on castings of CK20 alloy. It is important in all cases that the tool be kept continually entering into the metal in order to avoid work-hardening the surface from rubbing or scraping. Slow feeds, deep cuts, and powerful, rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully.

Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast ASTM: A351, A743 (CK20); A451 (CPK20); AMS 5365A; SAE 60310. Wrought AISI 310.

Corrosion Resistant Type CN7M 8161 IRUPHUO\(UNS J95150)

Description Type CN7M covers a group of related complex iron-nickel-chromiummolybdenum-copper alloys that contain more nickel than chromium. The high nickel content, together with the added elements molybdenum and copper, give these alloys especially good resistance to sulfuric acid and many reducing chemicals. Among the alloys included in this type designation, the so-called "20" alloy is produced in greatest quantity. Data for this grade are given in the "Summary of Properties". Whereas the chromium predominant alloys have poor or no resistance to hydrochloric acid, type CN7M has good resistance to dilute acid and hot chloride salt solutions. The alloy also will resist nitric acid satisfactorily. In the heat treated condition, type CN7M has an austenitic structure. As in the ironchromium-nickel grades, carbides must be put into solution by heat treatment to provide maximum corrosion resistance and to eliminate susceptibility to intergranular attack. Castings later exposed to temperatures in the range 800 to 1600°F (427 to 871°C) must be heat treated again to restore full corrosion resistance. Type CN7M cannot be hardened by heat treatment. Castings of the CN7M type have excellent machining and fair welding characteristics. Thermal expansion and other physical properties are comparable to the CF grades. The alloy is virtually non-magnetic.


P

S

0.04

0.04

Cr 19 22

Ni 27.5 30.5


Cu 3.0 4.0

Fe bal

24 0.289 0.11 0.896 2650 1.01- 1.1 Mean coefficient of Linear thermal expansion : in./in./ oF ______________________

______________________ At 212 oF

Mo 2.0 3.0

70 - 212 oF 70 - 1000 oF

12.1

8.6 9.7


69.0 31.5 48 130 70


Heat Treatment For maximum corrosion resistance, castings of CN7M alloy should be heated to 2050°F (1121°C) minimum, and then quenched in water, oil or air to ensure complete solution of carbides. Holding time at temperature will vary with the thickness of casting sections involved, but should be sufficiently long to heat all sections to a uniform temperature throughout. Applications The following lists of consuming industries, cast parts, and corrosive materials are useful as examples of typical applications where type CN7M alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses.

Industries Chemical Processing, Food Processing, Metal Cleaning and Plating, Mining, Munitions Manufacturing, Oil Refining, Paint and Pigment, Pharmaceutical, Plastics, Pulp and Paper, Soap and Detergent, Steel Mill, Synthetic Rubber, Textile and Dye. Castings Filter parts, fittings, heat exchanger parts, industrial mixer components, pickling rolls, pickling hooks and racks, pump parts, steam jets, tanks and towers, valve bodies and parts, ventilating fans. Corrosives Acetic acid (hot), brines, caustic solutions (strong, hot), hydrochloric acid (dilute), hydrofluoric and hydrofluosilicic acids (dilute), nitric acid (strong, hot), nitric-hydrofluoric pickling acids, sulfates and sulfites, sulfuric acid [all concentrations to 150°F (65.6°C), many to 176°F (80°C)], sulfurous acid, phosphoric acid, plating solutions. NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made to the extensive alphabetical lists of corrodents published by many alloy foundries and to corrosion data surveys published by the NACE to determine whether type CN7M is suitable for the particular corrosive involved, and the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. The mechanical and physical property data presented in tabular and graphical form are representative for alloy CN7M. These data are neither average nor minimum values, and should not be used for either specification or design purposes. Specification and/or design information may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in CN7M alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allowance for this alloy is 5/16 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type CN7M castings can be welded by metal-arc, inert-gas arc, and oxyacetylene gas methods. Metal-arc is most frequently used. Oxyacetylene welding is not advisable because of possible impairment of corrosion resistance caused by carbon pick-up. Castings normally are not preheated, but may be heated to 400 to 600°F (204 to 316°C) if the extent of the weld is substantial. This is most important in restrained sections since the weld metal is susceptible to cracking. After welding, the castings should be slowly cooled and then reheated to 2050°F (1121°C) and water quenched. Lime coated electrodes of similar composition (AWS E32015) are recommended. Welding procedures utilizing SMAW, GMAW, and GTAW techniques are described in this section. Machining Most machining operations can be performed readily on castings of CN7M alloy. It is important in all cases that the tool be kept continually entering into the metal in order to avoid work-hardening the surface. Slow feeds, deep cuts, and powerful, rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Chips are short and brittle. Characteristic large grains of this alloy may tend to cause uneven machined surfaces.

Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is recommended for high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast ASTM: A351, A743, A744 (CN7M). Wrought None.

Corrosion Resistant Type CX2MW (UNS N26022)

Description Type CX2MW is a cast nickel-chromiummolybdenum-tungsten alloy widely used alone or in conjunction with wrought nickelchromium -molybdenum-tungsten alloys. The alloy has good strength and toughness at cryogenic temperatures. Its microstructure consists of an austenitic matrix with some grain boundary precipitates. The alloy is resistant to pitting, crevice corrosion, stress corrosion cracking, and oxidizing conditions, including wet chlorine, and mixtures containing nitric or oxidizing acids. Wrought and cast alloys differ in the amount of the minor elements because of the different requirements for processing by rolling and processing by casting. However, these differences in chemical composition are minor and do not interfere with wrought-to-cast fabrication.


P

S

Cr 20.0 0.025 0.025 22.5

Physical properties Modulus of elasticity, psi x 106 Density, lb/in3 Sp. Heat, Btu/lb.oF, at 70 oF Electrical resistivity, :S.m, at 70 oF Melting point, approximate oF Thermal conductivity Btu/(ft.h. oF) ______________________ At 212 oF

77

Applications

bal.

Fe 2 6

Mo 12.5 14.5

W 2.5 3.5

29.9 0.314 0.99 44.8 2475-2550 Mean coefficient of Linear thermal expansion : in./in./ oF ______________________ 75 - 212 oF 70 - 1000 oF

6.9 7.7

Mechanical properties at room temperature Minimum tensile requirements ASTM A494 _____________

Heat Treatment Heat treatment consists of a solution treatment at 2200oF minimum followed by water quenching or rapid cooling by other means.

Ni

Tensile strength, ksi Yield strength, 0.2% offset, ksi Elongation, in 2in., % Brinell hardness (HBW)

80 45 30 -

The following lists of consuming industries, cast parts, and corrosive materials are useful as examples of typical applications where type CX2MW alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Chemical Processing, Cellophane Manufacturing, Chlorination Systems, Flue Gas Scrubbers, Geothermal Wells, Heat Exchangers, HF Furnace Scrubbers, Incineration Scrubbers, Nuclear Fuel Reprocessing, Pesticide Production, Phosphoric Acid Production, Pickling Systems, Refining, SO2 Cooling Towers, Sulfonation Systems. Castings Fittings, heat exchanger parts, pump parts, valve bodies and parts. Corrosives Acetic acid/acetic anhydride, acid etching, hydrofluoric acid, 2%HF/20%HCl at 170oF,salt air. NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial

operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made to the extensive alphabetical lists of corrodents published by many alloy foundries and to corrosion data surveys published by the NACE to determine whether type CX2MW is suitable. Also, the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. Information on specification and/or design may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in CX2MW alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allowance for this alloy is 9/32 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding CX2MW castings can be repair welded or fabrication welded to matching wrought alloys by all of the usual welding processes. Rod and wire of matching nickel-chromium-molybdenum-tungsten contents are available. Post-weld heat treatment may be required after repair welding or fabrication. Machining Machinability of CX2MW requires heavy cuts at slow cutting speeds because of the tendency of the alloy to work harden. Casting designations, specifications, and corresponding wrought alloy Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast ASTM: A494 (CX2MW (UNS N26022)). Wrought Hastelloy C-22 (UNS 06022).

Corrosion Resistant Type CY40 (UNS N06040)

Description Type CY40 is a cast nickel-chromium alloy widely used alone or in conjunction with wrought nickel-chromium alloys. The alloy has good strength and toughness from cryogenic to elevated temperatures. Its microstructure consists of an austenitic matrix with a uniform distribution of carbide particles. The alloy is resistant to oxidizing conditions, and is used to handle hot corrosives or corrosive vapors under conditions where the austenitic stainless steels might be subject to intergranular attack or stress corrosion cracking. The nickel content of CY40 is high enough so that its behavior is similar to that of CZ100 in resistance to hot caustic or alkaline solutions. Where cast-to-wrought fabrication is required for handling hot concentrated alkalies, CY40 usually can be substituted for low carbon CZ100. Generally, sound castings are more easily produced with type CY40 than with CZ100. Wrought and cast alloys differ in the amount of the minor elements because of the different requirements for processing by rolling and processing by casting. However, these differences in chemical composition are minor and do not interfere with wrought-to-cast fabrication. The somewhat lower mechanical properties for cast products are compensated for by heavier cast sections in cast-to-wrought fabrication.


P

S

0.03

0.03

Cr 14.0 17.5

Ni

Fe

bal.

11.0



______________________ At 212 oF

70 - 212 oF 70 - 1000 oF

Mechanical properties at room temperature Representative values Water quench from above 2050 oF __________________ Tensile strength, ksi Yield strength, 0.2% offset, ksi Elongation, in 2in., % Brinell hardness (HBW)


In elevated temperature service, CY40 is usually produced with a minimum carbon content of 0.20% to improve elevated temperature properties. Typical elevated temperature properties are shown in the accompanying tables. CY40 is less susceptible to intergranular corrosion than the cast stainless steels. The reason for this improved behavior is a less pronounced chromium depletion in the grain boundary areas, and the high nickel content which provides a more corrosion resistant matrix than can be provided in the iron-based stainless steels. Heat Treatment Because CY40 is less susceptible to intergranular corrosion, following sensitizing treatments, than the austenitic stainless steel, it is used in the as-cast condition for most applications. However, for nuclear applications and

for applications where very severe corrosive conditions are anticipated, CY40 is cast with a low carbon content and solution treated at 1900°F (1038°C) minimum. Unless residual stresses pose a problem, post-weld heat treatment is not required. Applications The following lists of consuming industries, cast parts, and corrosive materials are useful as examples of typical applications where type CY40 alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Chemical Processing, Power Plant, Nuclear. Castings Fittings. Corrosives Hot boiler feed water, hot caustics, hot concentrated alkalines, elevated temperature oxidizing conditions. NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made to the extensive alphabetical lists of corrodents published by many alloy foundries and to corrosion data surveys published by the NACE to determine whether type CY40 is suitable. Also, the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. The mechanical property, physical property, and corrosion data presented here are representative for alloy CY40. These data are neither average nor minimum values, and should not be used for either specification or design purposes. Information on specification and/or design may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in CY40 alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allowance for this alloy is 9/32 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding CY40 castings can be repair welded or fabrication welded to matching nickel-chromium wrought alloys by all of the usual welding processes. Rod and wire of matching nickel-chromium contents are available. Postweld heat treatment is not required after repair welding or fabrication because the heat affected zone is not sensitized by the weld heat. Welding procedures utilizing SMAW, and GTAW techniques are described in this section. Machining Machinability of CY40 is somewhat better than that of cast stainless steels. Heavy cuts at slow cutting speeds are recommended because of the tendency of the alloy to work harden. Recommended machining speeds are shown in the accompanying table.

Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast ASTM: A743 (CY40); A744 (CY40); A494 (CY40). Wrought An 0.08% max. C alloy would be similar to Inconel 600.

Elevated-Temperature Tensile Properties of CY40 Temp oF

0.2% Yield Strength, ksi

Tensile Strength, ksi

Elongation, %

Room

42

70.5

16

900

-

62

20

1200

-

54.5

21

1350

-

45.5

25

1500

-

27

34

100 Hour Rupture Strength of CY-40 Temp oF

Rupture Strength, ksi

1200

24

1350

15

1500

9

1700

5.5

Corrosion Resistant Type CZ100 (UNS N02100)

Description Type CZ100 is commercially pure nickel with a minimum of added elements to provide the casting and solidification characteristics necessary for the production of good castings. Although used in a variety of applications, the most common use of type CZ100 is in the handling of anhydrous caustic and hot concentrated caustic in caustic manufacture, and in caustic processing. Type CZ100, in comparison to stainless steels, has high thermal and electrical conductivity and a low coefficient of expansion. Type CZ100 retains strength and toughness over a wide range of temperatures - cryogenic to 1000°F+. The alloy is magnetic. Heat Treatment Type CZ100 is used in the as-cast condition. The alloy cannot be hardened by heat treatment, nor is behavior under corrosive conditions altered by heat treatment. Applications


P

S

Ni

Cu

Fe

0.03

0.03

95

1.25

3.0

Physical properties Modulus of elasticity, psi x 106 Density, lb/in3 Sp. Heat, Btu/lb.oF, at 70 oF Electrical resistivity, :S.m, at 70 oF Melting point, approximate oF Magnetic permeability Thermal conductivity Btu/(ft.h. oF) ______________________ At 212 oF

Mean coefficient of Linear thermal expansion : in./(in. oF) ______________________ 70 - 212 oF 70 - 1000 oF

Mechanical properties at room temperature Representative values Water quench from above 2050 oF __________________


Type CZ100 is most commonly used in handling hot concentrated, caustic Tensile strength, ksi 50.0 solutions. The 3% maximum limit for iron Yield strength, 0.2% offset, ksi 18.0 is based on corrosion testing results in Elongation, in 2in., % 10 hot concentrated and anhydrous caustic. Brinell hardness (HBW) Type CZ100 is most commonly cast with 0.6, 0.7 to 0.9% carbon which is present in the cast product as graphite spheroids. The graphite does not interfere with corrosion resistance of the alloy in any of its applications. The exception where a low carbon nickel should be specified is for applications involving cast-to-wrought welded sections where the welding operation results in grain boundary graphitization and consequent loss in strength and ductility. Graphite has no known detrimental effects on the corrosion resistance of CZ100; moreover, the graphite has a highly beneficial effect on casting quality. Castability is greatly improved because the metal is cleaner, can be poured at lower temperature, and solidification shrinkage is substantially reduced. The net result is a cleaner, sounder casting. Although the hardness of cast nickel is relatively low, the material has excellent resistance to erosion by hot caustic slurries. Nickel in pure alkaline solutions develops a passive layer which is apparently responsible for the good erosion resistance.

In processing with hot alkaline or caustic solutions where halides may be present, pitting attack can occur. Similarly, the presence of increasing amounts of halide in alkaline or caustic slurries results in measurable rates of erosion. The following lists of consuming industries, cast parts, and corrosive environments are useful as examples of typical applications where cast nickel (type CZ100) alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Chemical Processing, Mineral Processing, Food Processing. Castings Filter parts, fittings, heat exchanger parts, industrial mixer components, pump casings and parts, valve bodies and trim. Corrosives Nickel is useful in handling hot concentrated alkaline or caustic solutions, reducing acids, certain food products, organic acids under certain conditions, dry chlorine, and anhydrous ammonia. Cast nickel is not applicable in oxidizing acids and alkaline perchlorite. The high thermal conductivity of cast nickel is a useful property where heat transfer is important. NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made to the extensive alphabetical lists of corrodents published by many alloy foundries and to corrosion data surveys published by the NACE to determine whether type CZ100 is suitable. Also, the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. The mechanical property, physical property, and corrosion data presented here are representative for alloy CZ100. These data are neither average nor minimum values, and should not be used for either specification or design purposes. Information on specification and/or design may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Thin sections are readily cast in type CZ100 and, particularly with carbon in the 0.6%/0.9% range, the castability of type CZ100 approaches that of high strength cast irons. Normal pattern shrinkage allowance for type CZ100 is 1/8" per foot. Because, in many cases, type CZ100 is specified as an upgraded material from stainless steel, pattern equipment, particularly for larger castings, must be altered for lower pattern shrinkage allowance and rerigged for differences in solidification behavior. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type CZ100 is readily weldable with nickel electrodes and filler wire. AWS A5.11 Class ENi-1 covers coated electrodes, and AWS A5.14 Class ERNi-3 covers wire for GMAW and GTAW welding. No preheat is necessary, nor is postweld heat treatment required. Where cast nickel is to be joined to wrought nickel for high temperature service, a low carbon (.10 maximum) cast nickel should be specified. Welding procedure utilizing SMAW technique is described in this section. Machining Type CZ-100 with spheroidal graphite has excellent machinability compared to stainless steels. Most machining operations can be performed at a rate that is at least twice that of stainless steels. Speeds and feeds can be varied over a much wider range than those of stainless steel. The relatively high thermal conductivity of type CZ-100 and the lubricating and chip breaking effect of graphite in the microstructure make

the need for cutting fluids minimal. Excellent surface finish can be obtained. Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast ASTM: A743 (CZ100); A744 (CZ100); A494 (CZ100). Wrought ASTM:

B-160 Bar & Rod B-161 Pipe & Tube B-162 Plate, Sheet & Strip B-163 Seamless Tubes

Corrosion Resistant Type M-35 (M35-1 UNS N24135, M35-2 N04020)

Description The nickel-copper alloys represented by type M-35, grades 1 and 2, and QQ-N-288, grades A through E, contain approximately 30% copper, 67% nickel, and small amounts of iron and manganese are impurities. Silicon in amounts up to 4.5% is added to improve strength and resistance to wear and galling. With the exception of those grades containing over about 3.5% silicon, which are agehardenable, this alloy system has a single phase, face-centered-cubic microstructure. This alloy system is widely used in marine environments, mineral acids, organic acids, and strong alkalies. Heat Treatment M-35, 1 and 2, and QQ-N-288, compositions A and E, are employed in the as-cast condition. Homogenization at 1500 to 1700°F (816 to 927°C) may enhance corrosion resistance where iron is near the specified maximum in heavy section castings. However, under most corrosive conditions where the alloy is commonly applied, performance is not noticeably affected by the minor segregation occurring in the as-cast alloy. Beginning at about 3.5% minimum silicon, a silicide aging effect occurs in the high silicon grade composition D. Aging can occur during cooling from casting to room temperature, and is increasingly evident as cooling rate decreased with increasing section size. The combination of aging plus massive silicides which appear in the microstructure above about 3.8% silicon greatly reduces machinability.

Chemical composition - % M35-1 C Mn Si min. max. 0.35 1.50 1.25 M35-2 C min. max. 0.35

P

S

Ni

0.03

0.03

bal.

Mn

Si

P

S

Ni

1.50

2.00

0.03

0.03

bal.

Mo 2.0 3.0 Mo 2.0 3.0

Cu 26 33

Fe

Cb

3.5

0.5

Cu 26 33

Fe

Cb

3.5

0.5



______________________ At 212 oF

70 - 212 oF 70 - 1000 oF

Mechanical properties at room temperature Representative values Water quench from above 2050 oF __________________ Tensile strength, ksi Yield strength, 0.2% offset, ksi Elongation, in 2in., % Brinell hardness (HBW)

Minimum tensile requirements ASTM A494 M35-1 M35-2 65.0 25.0 25 -

65.0 30.0 25

Composition D can be softened for machining by solution heat treating at 1650°F (899°C), and air cooling or oil quenching. Maximum softening is attained by oil quenching, but may result in quench cracking in complex, variable section, and heavy section castings. In solution heat treating complex, variable section, and heavy section castings, it is advisable to charge into a furnace below 600°F (316°C), and heat to 1650°F (899°C) at a rate that will limit the maximum temperature difference within the casting to about 100°F (38°C). After soaking, castings that will not permit direct oil quenching should be transferred to a furnace held at 1350°F (732°C), allowed to equalize, then oil quenched.

Applications The following lists of consuming industries, cast parts, and corrosive environments are useful as examples of typical applications where nickel-copper alloys have been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Marine, Chemical Processing, Food Processing, Metal Cleaning and Plating, Oil Refining, Soap and Detergent. Castings Filter parts, fittings, pump casings and parts, valve bodies and trim. Corrosives Boiler water and steam condensate, sea water, unaerated sulfuric acid, hydrochloric acid, hydrofluoric acid, unaerated phosphoric acid, organic acids, halogens, alkalies, anhydrous ammonia, neutral and alkaline sales, acid salts. NOTE: Corrosion rate data obtained in carefully controlled laboratory tests using chemically pure reagents are helpful in screening alloys for further consideration, but the difference between such tests and commercial operation should not be overlooked. Concentration, temperature, pressure, contamination, and velocity of corrosives all influence the rate of attack, as do surface finish and casting design. Reference should be made to the extensive alphabetical lists of corrodents published by many alloy foundries and to corrosion data surveys published by the NACE to determine whether type M-35 is suitable. Also, the designer should provide the foundry with as much pertinent information as possible on operating conditions before reaching a definite decision to use this alloy. The mechanical and physical property and corrosion data presented here are representative for alloy M-35. These data are neither average nor minimum values, and should not be used for either specification or design purposes. Information on specification and/or design may be obtained from appropriate technical associations such as ASTM, ASME, API, NACE, and SAE. Design Considerations Section thicknesses from 1/8" upwards can be cast satisfactorily in the nickel-copper alloys. In designing for castings, uniform sections should be maintained, avoiding drastic changes in section. Isolated or internal heavy sections should be avoided if possible. Normal pattern shrinkage allowance for the nickel-copper alloys is 1/8" per foot. Because nickel-copper alloys are frequently specified as an alternative to steel or stainless steel, pattern equipment for heavy section or extensive castings may have to be altered because of the lower pattern shrinkage allowance and differences in solidification behavior. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding M-35, 1 and 2, and QQ-N-288, composition A and E, are readily weldable using matching nickelcopper content rod and wire. QQ-N-288, composition B, C, and D, are not weldable. Coated electrodes for arc welding are covered by AWS A5.11 Class E NiCu-2, and wire for GMAW and GTAW welding are covered by AWS A5.14 Class ER NiCu-7. In general, increasing silicon content reduces weldability of the nickel-copper alloys. Silicon, in addition to deoxidizing nickel-copper, acts as a solid solution hardener to improve strength. Where design considerations do not require high strength, the M-35, 1 and 2 grades, should be specified because of their good weldability. Columbium containing QQ-N-288, composition E, in the past, has been designated as "weldable grade nickel copper"; but with higher purity raw materials, the presence of columbium in castings is not needed to obtain good weldability. Welding procedures utilizing SMAW, and GTAW techniques are described in this section.

Machining Nickel-copper alloy M-35, 1 and 2, and compositions A and E can be machined in the cast condition at the speeds shown in the accompanying table. When only a limited amount of machining is necessary, nickel-copper composition D can be machined in the as-cast or aged conditions. However, because of the high hardness of composition D in these conditions, it should be annealed before machining, particularly if extensive machining is done on a production basis. Hardening can be accomplished after machining. High speed steel, cemented carbide or cast non-ferrous cutting tools may be used. Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast ASTM: A494 Wrought ASTM: None

STEEL CASTINGS HANDBOOK Supplement 9 High Alloy Data Sheets Heat Series


Heat Resistant Type HA

Description Type HA is an iron-chromiummolybdenum allow containing sufficient chromium to provide good resistance to oxidation at temperatures up to about 1200°F (699°C). The molybdenum content contributes desirable strength properties to the alloy at moderate temperatures. Castings of type HA alloy are widely used in oil refinery service. The alloy has a ferritic structure with carbides in pearlitic areas or agglomerated particles depending on prior heat treatment. Hardening of the alloy occurs on cooling in air from temperatures above 1500°F (816°C). In the normalized and tempered condition, the allow exhibits satisfactory toughness throughout its useful temperature range. Castings of type HA alloy have fairly good machining and welding properties if proper techniques are employed. The alloy is magnetic and has a low coefficient of thermal expansion comparable to carbon steel. At room temperature, the thermal conductivity is only about half that of carbon steel and the electrical resistivity is seven times higher. With increasing temperature, these differences decrease and, above about 1600°F (871°C), these differences are practically negligible. Heat treatment To obtain maximum softness, type HA castings should be annealed by heating to 1625°F (885°C) or slightly higher, and then slowly cooling in the furnace at about 50°F (10°C) per hour to below 1300° F (996°C) and then air cooling to below 1300°F (709°C) followed by tempering at about 1250°F (677°C).

Chemical composition - % C Mn Si min. 0.35 max. 0.20 0.65 1.00

P 0.04

S

Mo 0.90 0.045 1.20

Cr 8 12


Ni

Fe

-

bal

29 0.279 0.11 0.70 2750 Ferromagnetic

______________________



70 - 212 oF 70 - 600 oF 70 - 1000 oF 70 - 1200 oF

15.0 15.4 15.7 15.8

6.1 6.5 7.1 7.5

Mechanical properties at room temperature Representative values Normalized 1825 oF Annealed Tempered 1250 oF _________ ____________ Tensile strength, ksi 95.0 Yield strength, 0.2% 65.0 offset, ksi Elongation, in 2in., % 23 Reduction in area, % Brinell hardness (HBW) 180 Charpy V-notch, keyhole, ft.lbs -


107.0 81.0

90.0 60.0

21 56

18 35

220

-

32

-

At elevated temperatures Representative values - short time 1000 oF 1100 oF

Tensile ksi 67.0 44.0

Yield ksi 42.0 32.0

Elongation in 2 in. % 36

Reduction of area, % 71 58

Creep rupture properties Representative values1 - long time 1000 oF 1100 oF 1200 oF 1

Limiting creep stress, ksi 0.0001%/h 16.0 7.2 3.1

Stress to rupture 10h 100h 1000h 45.0 -

37.0 -

27.0 -

For constant temperature, for cyclic temperature lower values would apply

Applications The following lists of consuming industries, cast parts, and corrosive environments are useful as examples of typical applications where type HA alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries

Glass, Oil Refining

Castings Environment

Fan blades, furnace rollers, Lehr rolls, refinery fittings, trunnions Air, flue gases, petroleum, steam

NOTE: Proper selection of an alloy for a specific high temperature service involves consideration of some or all of the following factors: 1) required life of the part, 2) range frequency and speed of temperature cycling, 3) atmosphere and contaminants therein, 4) complexity of casting design, and 5) further fabrication of the casting. The criteria that should be used as the bases of alloy comparison will depend on the factors enumerated, and the designer will be aided in his choice by providing the foundry with as much pertinent information as possible on intended operating conditions before reaching a definite decision to use this alloy. The mechanical property and physical property data presented here in tabular and graphical form are representative for alloy HA. These data are neither average nor minimum values and should not be used for either specification or design purposes. Information on specification and/or design can be obtained from an appropriate technical association such as: ASTM, ASME, API, SAE and NACE. Design considerations Section thicknesses from 3/16 inch up can be cast satisfactory in HA alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Drastic changes in section should be avoided, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allowance for this alloy is 1/4 inch per foot. Fabricating considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type HA castings can be welded by metal-arc, inert-gas arc, and oxyacetylene gas methods. It is generally considered that metal-arc welding is more satisfactory for high temperature applications of this alloy than oxyacetylene welding. Castings should be heated to 450-550°F (232-288°C) before welding. After welding, castings should be heated to 1200-1300°F (699-709° C), depending on the original draw temperature, held sufficiently long to ensure uniform heating throughout the area and section involved, and then air cooled rapidly. Other welding procedures that are described under Alloy CA-15 are applicable to Alloy HA. Machining Most machining operations can be performed satisfactorily on castings of HA alloy. The work-hardening rate of this grade is much lower than that of the iron-chromium-nickel types, but it is advisable in all cases that the tool be kept continually entering into the metal. Slow feeds, deep cuts and powerful, rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Chips are stringy. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil

containing active sulfur and about 8 to 10 percent fatty oil is suggested for use with high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Other castings designations, specifications, and corresponding wrought alloy The wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast

ASTM: A217(C12), A426(CP9)

Wrought

ASTM: A199(T9), A200(T9)

Heat Resistant Type HC (UNS S92605)

Description Type HC is an iron-chromium allow containing about 28 percent chromium and up to 4 percent nickel. It provides excellent resistance to oxidation and highsulfur-containing flue gases at temperatures as high as 2000°F (1093°C). This grade is limited to applications where strength is not a consideration, or for moderate load bearing service around 1200°F (699°C). It is also used where appreciable nickel cannot be tolerated, as in very high sulfur atmospheres, or where nickel tends to crack hydrocarbons through catalytic action. The alloy has a ferritic structure at all temperatures and for this reason is not hardened by heat treatment. The ductility and impact strength are very low at room temperature, and the creep strength very low at elevated temperature, unless some nickel is present. In the HC type alloy containing over 2 percent nickel, substantial improvement in these properties is obtained by increasing the nitrogen content to 0.15 percent or more. Heating in the range 800 to 1050°F (427 to 566°C) will result in a loss of room temperature ductility and toughness. This loss is the so-called "885°F (475°C) embrittlement." In addition, this alloy is susceptible to sigma phase formation when heated for extended periods of time in the range 1100 to about 1600°F (593 to 871°C). Castings of type HC alloy are readily machinable. They can be welded successfully if proper technique is employed. The alloy is magnetic and has a lower coefficient of thermal expansion than to carbon steel.

Chemical composition - % C Mn Si P min. max. 0.50 1.00 2.00 0.04 1 Mo not intentionally added.

S

Mo

0.04

0.51

Cr 26 30


Ni

Fe

4

bal

29 0.272 0.12 0.77 2725 Ferromagnetic

________________

Mean coefficient of Linear thermal expansion : in./(in. oF) ____________________________________


70 - 1000 oF 70 - 1200 oF 70 - 1400 oF 70 - 1600 oF

12.6 15.4 15.7 15.8

6.3 6.4 6.6 7.0

70 - 1800 oF 70 - 2000 oF 1200 - 1600 oF 1200 - 1800 oF

7.4 7.7 8.7 9.3

Mechanical properties at room temperature Representative values As cast ___(a)___ Tensile strength, ksi 70.0 Yield strength, 0.2% 65.0 offset, ksi Elongation, in 2in., % 2 Brinell hardness 190 (HBW)

Aged 24h at 1400 oF Furnace cooled __(b)___(b)____

Minimum tensile requirements ASTM A297 ____________

110.0 115.0 75.0 80.0

55.0 -

19 223

-

18 -

At elevated temperatures - Creep rupture properties Representative values2 - long time 1400 oF 1600 oF 1800 oF

Limiting creep stress, ksi 0.0001%/h (b) 1.30 0.75 0.36

Stress to rupture 10h 100h 1000h (b) 4.6 2.0 1.1

(b) 3.30 1.70 0.85

2.30 1.30 0.62

2 For constant temperature, for cyclic temperature lower values would apply (a) <1.0% Ni, low N (b) >2.0% Ni, 0.15% min. N

At room temperature, the thermal conductivity is only about half that of carbon steel and the electrical resistivity is about eight times higher. With increasing temperature, these differences decrease and, above about 1600°F (871°C), these differences are practically negligible.

Heat Treatment Type HC castings are normally supplied in the as-cast condition. Applications The following lists of consuming industries, cast parts, and corrosive environments are useful as examples of typical applications where type HC alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Cement, Glass, Heat Treating, Industrial Furnace, Oil Refining, Ore Processing, Paper, Power, Zinc Refining. Castings Boiler baffles, electrodes, furnace grate bars, gas outlet dampers, kiln parts, lute rings, rabble blades and holders, recuperators, salt pots, soot blower tubes, support skids, tuyers. Environment

Air, combustion gases, flue gases, high sulfur, molten neutral salts.

NOTE: Proper selection of an alloy for a specific high temperature service involves consideration of some or all of the following factors: 1) required life of the part, 2) range frequency and speed of temperature cycling, 3) atmosphere and contaminants therein, 4) complexity of casting design, and 5) further fabrication of the casting. The criteria that should be used as the bases of alloy comparison will depend on the factors enumerated, and the designer will be aided in his choice by providing the foundry with as much pertinent information as possible on intended operating conditions before reaching a definite decision to use this alloy. The mechanical property and physical property data presented here in tabular and graphical form are representative for alloy HC. These data are neither average nor minimum values and should not be used for either specification or design purposes. Information on specification and/or design can be obtained from an appropriate technical association such as: ASTM, ASME, API, SAE and NACE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in HC alloy. Somewhat lighter sections are also feasible depending on casting design and pattern equipment. Some difficulty is encountered in running thin sections, however, and designs involving appreciable changes in section should be avoided. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allowance for this alloy is 7/22 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type HC castings can be welded by metal-arc, inert-gas arc, and oxyacetylene gas methods. It is generally considered that metal-arc welding is more satisfactory for high temperature applications of this alloy than oxyacetylene welding. Castings should be heated to 400-800°F (232-427°C) before welding. After welding, castings should be heated to 1550°F (843° C),held sufficiently long to ensure uniform heating throughout the area and section involved, and then air cooled rapidly. Welding procedures utilizing SMAW and GTAW techniques are described in this section.

Machining Most machining operations can be performed satisfactorily on castings of HC alloy. It is important in all cases that the tool be kept continually entering into the metal to avoid work-hardening the surface. Slow feeds, deep cuts and powerful, rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Chips are tough and stringy; chip curler and breaker tools are recommended. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is suggested for use with high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26.

Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast

ASTM: A297(HC), A608(HC30), S A E 70446

Wrought

AISI 446

Heat Resistant Type HD (UNS J93005)

Description Type HD is an iron-chromium-nickel alloy very similar in general properties to the 28 percent chromium HC type, but containing about 5 percent nickel. Its high chromium content makes this grade suitable for use in high-sulfur atmospheres, and the addition of nickel provides somewhat greater strength at high temperatures for type HD than exhibited by the other "straight chromium" alloys with which it is frequently grouped. The alloy has a two-phase, ferrite plus austenite structure that is non-hardenable by customary heat treating procedure. Long exposure to temperatures in the range 1300 to 1500°F (704 to 816°C), however, may result in considerable hardening of the alloy accompanied by severe loss of room temperature ductility through formation of the sigma phase. Restoration of ductility may be accomplished by heating the alloy to a uniform temperature of 1800°F (982°C) or higher, and then cooling rapidly to below 1200°F (699°C). Castings of type HD alloy have good machining and welding properties. Electrical resistivity and thermal conductivity are similar to type HC, but thermal expansion coefficients are about 20 percent higher. The alloy is magnetic.

Chemical composition - % C Mn Si P min. max. 0.50 1.00 2.00 0.04 1 Mo not intentionally added.

S 0.04

Mo 0.5

1

Cr 26 30


Ni 4 7

Fe bal

27 0.274 0.12 0.81 2700 Ferromagnetic


Mean coefficient of Linear thermal expansion : in./(in. oF) _________________ _______________________________________


12.6 17.9 20.3 24.2

70 - 1000 oF 70 - 1200 oF 70 - 1400 oF 70 - 1600 oF

7.7 8.0 8.3 8.6

70 - 1800 oF 70 - 2000 oF 1200 - 1600 oF 1200 - 1800 oF

6.1 6.5 7.1 7.5

Mechanical properties at room temperature Representative values As cast ______ Tensile strength, ksi Yield strength, 0.2% offset, ksi Elongation, in 2in., % Brinell hardness (HBW)


85.0 48.0 16 190

75.0 35.0 8 -

At elevated temperatures Representative values - short time 1400 oF 1600 oF 1800 oF

Tensile ksi 36.0 23.0 15.0

Yield ksi -

Elongation in 2 in. % 14 18 40

Heat Treatment

Creep rupture properties

Type HD castings are normally supplied in the as-cast condition.

Representative values2 - long time

Limiting creep stress, ksi 0.0001%/h

Stress to rupture 10h 100h 1000h

Applications

1400 oF 1600 oF 1800 oF 1600 oF

3.5 1.9 0.9 0.2

14.0 -

10.0 5.0 2.5 -

7.0 -

The following lists of consuming industries, cast parts, and corrosive 2 For constant temperature, for cyclic temperature lower values would apply environments are useful as examples of typical applications where type HD alloy has been employed successfully; they are not comprehensive nor are they intended as guides to alloy selection for specific end uses. Industries

Copper, Glass, Heat Treating, Oil Refining, Ore Processing, Steel.

Castings Brazing furnace parts, cracking equipment, furnace blowers, gas burner parts, holding pots, kiln parts, pouring spouts, rabble shoes and arms, recuperator sections, salt pots. Environment neutral salts.

Air, combustion gases, flue gases, high sulfur, molten copper and copper alloys, molten

NOTE: Proper selection of an alloy for a specific high temperature service involves consideration of some or all of the following factors: 1) required life of the part, 2) range frequency and speed of temperature cycling, 3) atmosphere and contaminants therein, 4) complexity of casting design, and 5) further fabrication of the casting. The criteria that should be used as the bases of alloy comparison will depend on the factors enumerated, and the designer will be aided in his choice by providing the foundry with as much pertinent information as possible on intended operating conditions before reaching a definite decision to use this alloy. The mechanical property and physical property data presented here in tabular and graphical form are representative for alloy HD. These data are neither average nor minimum values and should not be used for either specification or design purposes. Information on specification and/or design can be obtained from an appropriate technical association such as: ASTM, ASME, API, SAE and NACE. Design Considerations Section thickness from 3/16 inch up can be cast satisfactorily in HD alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Some difficulty is encountered in running thin sections, however, and designs involving appreciable changes in section should be avoided. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allowance for this alloy is 7/22 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding . Type HD castings can be welded by metal-arc, inert-gas arc, and oxyacetylene gas methods. It is generally considered that metal-arc welding is more satisfactory for high temperature applications of this alloy than oxyacetylene welding. The welding procedures outlined for Alloy HC are applicable for Alloy HD. Welding procedures utilizing SMAW and GTAW techniques are described in this section. Machining Most machining operations can be performed satisfactorily on castings of HD alloy. It is important in all cases that the tool be kept continually entering into the metal to avoid work-hardening the surface. Slow feeds, deep cuts and powerful, rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Chips are tough and stringy; chip curler and breaker tools are recommended. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is suggested for use with high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26.

Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast

ASTM: A297(HD), A608(HD30), S A E 70327

Wrought

AISI 327

Heat Resistant Type HE (UNS J93403)

Description Type HE is an iron-chromium-nickel alloy containing enough chromium to be suitable for service up to 2000°F (1093°C) but also having sufficient nickel to make it stronger and more ductile than the "straight chromium" types at room temperature in the ascast condition. At high temperatures, the alloy has excellent corrosion resistance, good ductility and moderate strength. It is the strongest grade having good resistance to veryhigh-sulfur-content gases (300 to 500 grains sulfur per 100 cubic feet of gas) at high temperatures. For this reason, type HE castings are used extensively in ore-roasting equipment. In the as-cast condition the alloy has a two-phase, austenite plus ferrite structure containing carbides. Type HE castings cannot be hardened by heat treatment, but, like the HD grade, long exposure to temperatures around 1500°F (816°C) will promote formation of the sigma phase with consequent embrittlement of the alloy at room temperature. Ductility of this grade can be improved somewhat by quenching the alloy from about 2000°F (1093°C). Castings of type HE alloy have good machining and welding properties. At room temperature, thermal expansion is about 50 percent greater than for carbon steel or the iron-chromium HC type. Also, at room temperature, thermal conductivity is much lower than for types HD or HC, but electrical resistivity is about the same. The alloy is weakly magnetic.

Chemical composition - % C Mn Si P min. 0.20 max. 0.50 2.00 2.00 0.04 1 Mo not intentionally added.

S

Mo

0.04

0.51

Cr 26 30


Fe bal

25.0 0.277 0.14 0.85 2650 1.3 - 2.5

Mean coefficient of Linear thermal expansion : in./(in. oF) ____________________________

_________________ At 212 oF At 600 oF At 1000 oF At 1200 oF At 1400 oF At 1600 oF At 1800 oF At 2000 oF

Ni 8 11

70 - 1000 oF 70 - 1200 oF 70 - 1400 oF 70 - 1600 oF 70 - 1800 oF 70 - 2000 oF 1200 - 1600 oF 1200 - 1800 oF

8.5 10.5 12.4 13.5 14.6 15.9 16.9 18.2

9.6 9.9 10.2 10.5 10.8 11.1 12.2 12.5

Mechanical properties at room temperature Representative values Aged 24h As cast at 1400 oF Furnace cooled ______ _____________ Tensile strength, ksi 95.0 Yield strength, 0.2% 45.0 offset, ksi Elongation, in 2in., % 20 Brinell hardness 200 (HBW) Charpy keyhole, ft.lbs 10

Minimum tensile requirements ASTM A297 ____________

90.0 55.0

85.0 40.0

10 270

9 -

-

-

At elevated temperatures Creep rupture properties Representative values2 - long time

Limiting creep stress, ksi 0.0001%/h

1400 oF 1600 oF 1800 oF 1600 oF

4.0 1.9 0.9 0.2

Stress to rupture, ksi 100h 11.0 5.3 2.5 -

2


Heat Treatment Type HE castings are normally supplied in the as-cast condition. Applications The following lists of consuming industries, cast parts, and corrosive environments are useful as examples

of typical applications where type HE alloy has been employed successfully; they are not comprehensive nor are they intended as guides to alloy selection for specific end uses. Industries Oil Refining, Power, Smelting, Steel.

Castings Billet skids, burner nozzles, dampers, furnace chains and conveyors, furnace door frames, oil burner parts, rabble arms and blades, recuperators, rotating shafts, soot blower elements, steam generator parts, tube supports. Environment

Air, flue gases, high sulfur, steam.

NOTE: Proper selection of an alloy for a specific high temperature service involves consideration of some or all of the following factors: 1) required life of the part, 2) range frequency and speed of temperature cycling, 3) atmosphere and contaminants therein, 4) complexity of casting design, and 5) further fabrication of the casting. The criteria that should be used as the bases of alloy comparison will depend on the factors enumerated, and the designer will be aided in his choice by providing the foundry with as much pertinent information as possible on intended operating conditions before reaching a definite decision to use this alloy. The mechanical property and physical property data presented here in tabular and graphical form are representative for alloy HE. These data are neither average nor minimum values and should not be used for either specification or design purposes. Information on specification and/or design can be obtained from an appropriate technical association such as: ASTM, ASME, API, SAE and NACE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in HE alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Good castability of this alloy permits designs involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allowance for this alloy is 9/22 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type HE castings can be welded by metal-arc, inert-gas arc, and oxyacetylene gas methods. Metal-arc welding is generally preferred for high temperature applications of this alloy. Lime coated electrodes of similar composition (AWS E312-15) are suggested for arc welding. Neither preweld nor postweld heat treating is required. Additional details of welding procedures described for Alloy HH are applicable for Alloy HE. Welding procedures utilizing SMAW, GMAW and GTAW techniques are described in this section. Machining Most machining operations can be performed satisfactorily on castings of HE alloy. It is important in all cases that the tool be kept continually entering into the metal to avoid workhardening the surface. Slow feeds, deep cuts and powerful, rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Chips are tough and stringy; chip curler and breaker tools are recommended. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is suggested for use with high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools.

Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast

ASTM: A297(HE), A608(HE30), S A E 70312

Wrought

AISI 312

Heat Resistant Type HF (UNS J92603)

Description Type HF is an iron-chromiumnickel alloy similar to the wellknown type CF corrosion resistant composition (19 Cr. 9 Ni), but containing somewhat more chromium and nickel, and substantially more carbon. The increased chromium content confers added resistance to oxidation at elevated temperature, and the higher nickel and carbon levels ensure an austenitic structure; accordingly, this grade is suitable for applications requiring high strength and corrosion resistance in the range 1200 to 1600°F (649 to 871°C). It is used extensively in oil refinery and heat treating furnaces. As cast, the alloy has an austenitic matrix containing interdendritic eutectic carbides and occasionally an unidentified lamellar constituent. Aging at service temperatures is usually accompanied by precipitation of finely dispersed carbides resulting in higher room temperature strength and some loss of ductility. Improperly balanced alloys may be partially ferritic as cast, and such materials are susceptible to embrittlement from sigma phase formation after long exposure at 1400 to 1500°F (760 to 816°C). Castings of type HF alloy have good welding and machining properties. At room temperature, thermal expansion is about 40 percent greater than carbon steel or iron-chromium alloy types HA, HC and HD, and heat conductivity is 25 to 60 percent less. The alloy has


S

Mo

0.04

0.51

Cr 18 23


Ni 8 12

Fe bal

28.0 0.280 0.12 0.80 2550 1.00

________________

Mean coefficient of Linear thermal expansion : in./(in. oF) ______________________________________

At 212 oF At 600 oF At 1000 oF At 1200 oF At 1400 oF At 1600 oF

68 - 200 oF 68 - 400 oF 68 - 600 oF 68 - 800 oF 68 - 1000oF 68 - 1200oF

8.3 10.5 12.3 13.3 14.6 15.9

8.96 9.26 9.51 9.74 9.94 10.13

68 - 1400 oF 68 - 1600 oF 68 - 1800 oF 68 - 2000 oF 1200 - 1400 oF 1200 - 1600 oF

10.30 10.46 10.61 10.74 11.00 11.50

Mechanical properties at room temperature Representative values Aged 24h As cast at 1400 oF Furnace cooled ______ _____________

____________

92.0 45.0

100.0 50.0

70.0 35.0

38 165

25 190

25 -

Representative values - short time

Tensile ksi

Yield ksi

Elongation in 2 in. %

1200 oF 1400 oF 1600 oF

60.0 38.0 21.0

31.5 25.0 15.5

10 16 16


Minimum tensile requirements ASTM A297

At elevated temperatures

Creep rupture properties Representative Limiting creep stress, ksi values2 1% total creep in - long time 0.0001%/h 100,000 h o

1200 F 1400 oF 1600 oF 2 3

18.0 6.8 3.9

11.3 4.4 0.9

100

Stress to rupture in hours 1000 10,000 100,000

33.0 13.5 7.2

25.0 9.1 4.4

16.5 6.1 2.7

11.03 4.03 1.73

For constant temperature, for cyclic temperature lower values would apply Extrapolated

about five times the electrical resistance of carbon steel. It is normally non-magnetic. Heat Treatment Castings of type HF alloy are normally supplied in the as-cast condition. The alloy cannot be hardened by heat treatment, but, if service conditions involve repeated heating and cooling, improved performance may be obtained by heating castings at 1900°F (1038°C) for six hours followed by furnace cooling prior to placing in service. Applications The following lists of consuming industries, cast parts, and corrosive environments are useful as examples of typical applications where type HF alloy has been employed successfully; they are nor comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries

Aluminum, Cement, Glass, Heat Treating, Industrial Furnace, Oil Refining, Steel.

Castings Arc furnace electrode arms, annealing boxes and trays, baskets, brazing channels, burner tips, burnishing rolls, conveyor belts and chains, fan housings, furnace rails, gas burner rings, hardening retorts, hearth plates, Lehr rolls, pier caps, soaking pit dampers, tempering baskets, wear plates. Environment

Air, combustion gases, flue gases oxidizing and reducing, steam.

NOTE: Proper selection of an alloy for a specific high temperature service involves consideration of some or all of the following factors: 1) required life of the part, 2) range frequency and speed of temperature cycling, 3) atmosphere and contaminants therein, 4) complexity of casting design, and 5) further fabrication of the casting. The criteria that should be used as the bases of alloy comparison will depend on the factors enumerated, and the designer will be aided in his choice by providing the foundry with as much pertinent information as possible on intended operating conditions before reaching a definite decision to use this alloy. The mechanical property and physical property data presented here in tabular and graphical form are representative for alloy HF. These data are neither average nor minimum values and should not be used for either specification or design purposes. Information on specification and/or design can be obtained from an appropriate technical association such as: ASTM, ASME, API, SAE and NACE. Design Considerations Section thickness from 3/16 inch up can be cast satisfactorily in HF alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Good castability of this alloy permits designs involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allowance for this alloy is 1/22 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type HF castings can be welded by metal-arc, inert-gas arc, and oxyacetylene gas methods. Metal-arc welding is generally preferred for high temperature applications of this alloy. Neither preweld nor postweld heat treating is required. Welding procedures utilizing SMAW, GMAW and GTAW techniques are described in this section.

Machining Most machining operations can be performed satisfactorily on castings of HF alloy. It is important in all cases that the tool be kept continually entering into the metal to avoid work-hardening the surface. Slow feeds, deep cuts and powerful rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Chips are tough and stringy; chip curler and breaker tools are recommended. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is suggested for use with high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast

ASTM: A297(HF), A608(HF30), S A E 70308, MIL-S-17509(SHIPS)

Wrought

AISI 302B

Heat Resistant Type HH (UNS J93503)

Description Type HH is an iron-chromium-nickel alloy containing the minimum quantities of chromium and nickel in proportions to supply a useful combination of properties for elevated temperature service. The chromium range is high enough to ensure good scaling resistance up to 2000°F (1093°C) (and sometimes higher) in air or normal combustion gases. Sufficient nickel is present, aided by carbon, nitrogen and manganese, to maintain austenite as the major phase; but the alloy is borderline in character and its microstructure is very sensitive to composition balance. For high ductility near 1800°F (982°C) a structure exhibiting both austenite and ferrite is appropriate. Such an alloy is relatively weak, however, and if high strength is needed, and lower ductility can be tolerated, a composition balanced to be wholly austenitic is desirable. Fortunately, two distinct grades of material can be obtained within the stated chemical composition range of the type HH alloy. These grades are defined as Type I and Type II in ASTM Specification A447. The various useful properties obtainable in the type HH alloy make it suitable for a wide range of high temperature applications and, for this reason, it is used in greater quantity than any other heat resistant grade. The alloy is basically austenitic and holds considerable carbon in solid solution, but carbides, ferrite (soft, ductile and magnetic) and sigma (hard, brittle and non-magnetic) also may be present in the micro-structure. The amounts of the various structural constituents present depend on the chemical composition and the thermal history of the sample under consideration. Near 1600°F (871°C) the partially ferritic alloys tend to embrittle from development of the sigma phase, while around 1400°F


S

Mo

0.04

0.51

Cr 24 28

Physical properties Modulus of elasticity, psi x 106 Density, lb/in3 Sp. Heat, Btu/lb.oF, at 70 oF Electrical resistivity, :S.m, at 70 oF Melting point, approximate oF Magnetic permeability Thermal conductivity Btu/(ft.h. oF) ________________ At 212 oF At 600 oF At 1000 oF At 1200 oF At 1400 oF At 1600 oF At 1800 oF At 2000 oF 2

8.2 10.1 12.0 13.0 14.1 15.3 16.32 17.52

Ni 11 14

Fe bal

27.0 0.279 0.12 0.75 - 0.85 2500 1.00 - 1.9

Mean coefficient of Linear thermal expansion : in./(in. oF) ______________________________________ 70 - 1000 oF 70 - 1200 oF 70 - 1400 oF 70 - 1600 oF

9.5 9.7 9.9 10.2

70 - 1800 oF 70 - 2000 oF 1200 - 1600 oF 1200 - 1800 oF

10.5 10.7 11.4 11.7

Estimated

Type I - Partially ferritic Mechanical properties at room temperature Representative values Aged 24h As cast at 1400 oF Furnace ______ cooled___ Tensile strength, ksi Yield strength, 0.2% offset, ksi Elongation, in 2in., % Brinell hardness (HBW)


85.0 50.0

86.0 55.0

75.0 35.0

25 185

11 200

10 -


Tensile ksi

Yield ksi


1200 oF 1400 oF 1600 oF 1800 oF

33.0 18.5 9.0

17.0 13.5 6.3

18 30 45

At elevated temperatures

Creep rupture properties Representative values3 - long time 1400 oF 1600 oF 1800 oF 2000 oF

Limiting creep stress, ksi (rate 0.0001%/h) 3.0 1.7 1.1 0.3

Stress to rupture in hours 10 100 1,000 4.7 -

14.0 6.4 3.1 1.5

6.5 3.8 2.1 -


(760°C) carbide precipitation may cause a comparable loss of ductility. Such possible embrittlement suggests that 1700 to 2000°C (927 to 1093°C) is the best service temperature range, but this is not critical for steady temperature conditions in the absence of unusual thermal or mechanical stresses. A serious cause of embrittlement is absorption of carbon from the service environment. Accordingly, the HH type alloy is seldom used for carburizing applications. High silicon content (over 1.5 percent) will fortify the alloy against carburization under mild conditions but will promote ferrite formation and possible sigma embrittlement. Thus, although the HH type alloy can give satisfactory service in carburizing atmospheres, types HT, HU, HW and HX are considered superior and are generally preferred for such application, particularly where thermal shock is involved.

Type II - Wholly austenitic Mechanical properties at room temperature Representative values Aged 24h As cast at 1400 oF Furnace A297 cooled ______ ________ Tensile strength, ksi 80.0 Yield strength, 0.2% 40.0 offset, ksi Elongation, in 2in., % 15 Brinell hardness (HBW) 180 Impact, Charpy keyhole (see Fig. 1)

Minimum tensile requirements ASTM ____________

92.0 45.0

75.0 35.0

80.0 -

8 200

10 -

4 -

Yield ksi


At elevated temperatures Representative values - short time

Tensile ksi

o

1200 F 60.5 32.2 14 The partially ferritic (Type I) HH alloy 1400 oF 37.4 19.8 16 is frequently considered best adapted 1600 oF 21.5 16.0 18 1800 oF 10.9 7.3 31 to operating conditions which are 2000 oF 5.5 subject to changes in temperature level and applied stress. A plastic Creep rupture properties Representative values3 - long time extension in the weaker, ductile ferrite under changing load tends to occur Limiting stress, 1% creep Stress to rupture in more readily than in the stronger ksi, creep in, ksi stress, ksi hours austenitic phase, thereby reducing rate 0.0001%/h 100,000 100 1,000 10,000 100,000 unit stresses and stress concentrations and permitting rapid 1200 oF 18.0 9.5 35.0 22.00 14.00 9.004 o 1400 F 6.3 2.0 14.0 8.00 4.80 2.804 adjustment to suddenly applied o 1600 F 3.9 1.1 6.8 3.80 2.15 1.204 overloads without cracking. Where 1800 oF 2.1 3.2 1.65 0.864 0.444 load and temperature conditions are 2000 oF 0.8 1.4 0.68 0.344 0.154 comparatively constant, the wholly 3 For constant temperature, for cyclic temperature lower values would apply austenitic (Type II) HH alloy provides 4 Extrapolated the highest creep strength and permits use of maximum design stress. The stable austenitic alloy is also favored for cyclic temperature service that might induce sigma phase formation in the partially ferritic type.

Castings of type HH alloy have good weldability and fair machining characteristics. At room temperature, thermal expansion is about 40 percent greater than carbon steel or iron-chromium alloy types HC or HD and almost 10 percent more than the nickel-predominant types such as HT or HW. Also, at room temperature, electrical resistance is about five times that of carbon steel. The alloy varies from non-magnetic to weakly magnetic. The magnetic permeability increases with the amount of the ferrite phase present, but decreases if the ferrite is converted to sigma phase. Thus, this property can be used to indicate constitution and, under the proper conditions, to estimate high temperature strength. Heat Treatment Castings of type HH alloy are normally supplied in the as-cast condition. The alloy cannot be hardened by

heat treatment. For alloys of medium carbon content (about 0.30%) in applications involving thermal fatigue from rapid heating and cooling, improved performance sometimes may be obtained by heating castings at 1900°F (1038°C) for 12 hours followed by furnace cooling prior to placing in service. Applications The following lists of consuming industries, cast parts, and corrosive environments are useful as examples of typical applications where type HH alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Cement, Chemical, Furnace, Construction, Glass, Heat Treating, Oil Refining, Ore Refining, Steel. Castings Annealing trays, billet skids, burner nozzles, carburizing boxes, convection tube supports, dampers exhaust manifolds, flue gas stacks, grate supports, hardening trays, kiln nose ring segments, muffles, normalizing discs, pier caps, quenching trays, rabble arms and blades, radiant tubes and supports, refractory supports, retorts, roller hearths and rails, stoker parts, tube hangers. Environment Air, ammonia, carburizing gas, combustion gases, flue gases oxidizing and reducing, high sulfur gases, molten cyanide, steam, tar. NOTE: Proper selection of an alloy for a specific high temperature service involves consideration of some or all of the following factors: 1) required life of the part, 2) range frequency and speed of temperature cycling, 3) atmosphere and contaminants therein, 4) complexity of casting design, and 5) further fabrication of the casting. The criteria that should be used as the bases of alloy comparison will depend on the factors enumerated, and the designer will be aided in his choice by providing the foundry with as much pertinent information as possible on intended operating conditions before reaching a definite decision to use this alloy. The mechanical property and physical property data presented here in tabular and graphical form are representative for alloy HH. These data are neither average nor minimum values and should not be used for either specification or design purposes. Information on specification and/or design can be obtained from an appropriate technical association such as: ASTM, ASME, API, SAE and NACE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in HH alloy. Somewhat lighter sections are also feasible depending on casting design and pattern equipment. Good castability of this alloy permits designs involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allow for this alloy is 5/16 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type HH castings can be welded by metal-arc, inert-gas arc, and oxyacetylene gas methods. Metal-arc welding is generally preferred for high temperature applications of this alloy. Neither preweld nor postweld heat treating is required. Welding procedures utilizing SMAW, GMAW and GTAW techniques are described in this section.

Machining Most machining operations can be performed satisfactorily on castings of HH alloy. It is important in all cases that the tool be kept continually entering into the metal to avoid workhardening the surface. Slow feeds, deep cuts and powerful rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is suggested for use with high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast

ASTM: A297(HH), A447, A608(HH33), SAE 70309

Wrought

AISI 309

Heat Resistant Type HI (UNS J94003)

Description Type HI is an iron-chromium-nickel alloy similar to type HH, but containing more nickel and chromium. The increased chromium content makes this grade more resistant to oxidation than the HH type and the additional nickel serves to maintain good strength of high temperature. Exhibiting adequate strength, ductility and corrosion resistance, this alloy has been used extensively for retorts operating with an internal vacuum at continuous temperature of 2150°F.


Castings of type HI alloy have good weldability and fair machining characteristics. At room temperature, thermal expansion is about 50 percent greater than carbon steel or iron-chromium alloy types HC and HD, and heat conductivity is about 40 percent less. The alloy is virtually non-magnetic. Heat Treatment Castings of type HI alloy are normally supplied in the as-cast condition. Applications The following lists of consuming industries, cast parts, and corrosive environments are useful as examples of typical applications where type HI alloy has been employed

0.04

Mo 0.5

1

Cr 26 30

Physical properties Modulus of elasticity, psi x 106 Density, lb/in3 Sp. Heat, Btu/lb.oF, at 70 oF Electrical resistivity, :S.m, at 70 oF Melting point, approximate oF Magnetic permeability Thermal conductivity Btu/(ft.h. oF) ________________

The alloy has a predominantly austenitic structure containing carbides and, depending on the exact composition balance, may or may not contain small amounts of ferrite. Aging at 1400 to 1600°F (760 to 871°C) is accompanied by precipitation of finely dispersed carbides which tend at room temperature to increase mechanical strength and to decrease ductility. Following service at temperatures to increase the room temperature mechanical strength and to decrease the ductility above 2000°F (1093°C), however, such carbides remain in solution and room temperature ductility is not impaired.

S

At 212 oF At 600 oF At 1000 oF At 1200 oF At 1400 oF At 1600 oF At 1800 oF At 2000 oF

Ni 14 18

Fe bal

27.0 0.279 0.12 0.85 2550 1.00 - 1.7

Mean coefficient of Linear thermal expansion : in./(in. oF) ______________________________________ 70 - 1000 oF 70 - 1200 oF 70 - 1400 oF 70 - 1600 oF 70 - 1800 oF 70 - 2000 oF 1200 - 1600 oF 1200 - 1800 oF

8.2 10.1 12.0 13.0 14.1 15.3 16.3 17.5

9.9 10.0 10.1 10.3 10.5 10.8 11.0 12.0

Mechanical properties at room temperature Representative values Aged 24h As cast at 1400 oF Furnace ______ cooled___

Minimum tensile requirements ASTM A297 _____

80.0 45.0

90.0 65.0

70.0 35.0

12 180

6 200

10 -


Tensile ksi

Yield ksi


1200 oF 1400 oF

38.0 26.0

-

6 12

Tensile strength, ksi Yield strength, 0.2% offset, ksi Elongation, in 2in., % Brinell hardness (HBW) At elevated temperatures

Creep rupture properties Representative values3 - long time 1400 oF 1600 oF 1800 oF 2000 oF 2150 oF 2

Limiting creep stress, ksi (rate 0.0001%/h) 6.60 3.60 1.90 0.80

Stress to rupture in hours 100 1,000 13.0 7.5 4.1 1.9

8.50 4.80 2.60 1.25


successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries

Heat Treating, Magnesium Reducing, Steel.

Castings Billet skids, brazing fixtures, conveyor rollers, furnace rails, hearth plates, lead pots, pier caps, retorts, tube spacers. Environment

Air, flue gases oxidizing and reducing, molten lead.

NOTE: Proper selection of an alloy for a specific high temperature service involves consideration of some or all of the following factors: 1) required life of the part, 2) range frequency and speed of temperature cycling, 3) atmosphere and contaminants therein, 4) complexity of casting design, and 5) further fabrication of the casting. The criteria that should be used as the bases of alloy comparison will depend on the factors enumerated, and the designer will be aided in his choice by providing the foundry with as much pertinent information as possible on intended operating conditions before reaching a definite decision to use this alloy. The mechanical property and physical property data presented here in tabular and graphical form are representative for alloy HI. These data are neither average nor minimum values and should not be used for either specification or design purposes. Information on specification and/or design can be obtained from an appropriate technical association such as: ASTM, ASME, API, SAE and NACE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in HI alloy. Somewhat lighter sections are also feasible depending on casting design and pattern equipment. Good castability of this alloy permits designs involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allow for this alloy is 5/16 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding The welding procedures outlined for Alloy HH are applicable for Alloy HI. Welding procedures utilizing SMAW, GMAW and GTAW techniques are described in this section. Machining Most machining operations can be performed satisfactorily on castings of HI alloy. It is important in all cases that the tool be kept continually entering into the metal to avoid work-hardening the surface. Slow feeds, deep cuts and powerful rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is suggested for use with high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy

The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast

ASTM: A297(HI), A608(HI35)

Wrought

None

Heat Resistant Type HK (UNS J94224)

Description Type HK is an iron-chromium-nickel alloy somewhat similar to a wholly austenitic type HH in general characteristics and mechanical properties. Although not quite as resistant to oxidizing gases as types HC, HE, OR HI, the HK alloy has chromium content high enough to ensure good resistance to corrosion by hot gases, in both oxidizing or reducing conditions. The high nickel content helps to make the HK grade one of the strongest heat resistant casting alloys at temperatures above 1900°F (1038°C). Accordingly, HK type castings are widely used for stressed parts in structural applications up to 2100°F (1149°C). As normally produced, the HK alloy type is stable austenitic over its entire temperature range of application. The as-cast microstructure consists of an austenite matrix containing massive carbides as scattered islands or networks. After aging at service temperature, the alloy exhibits a dispersion of fine, granular carbides within the austenite grains, with subsequent agglomeration if the temperature is high enough. These fine, dispersed carbides contribute to the creep strength of the alloy. A lamellar constituent tentatively identified as an austenite, carbonitride eutectoid resembling pearlite also is frequently observed in HK alloys but its exact nature is in doubt. Except when present in excessive amounts, however, it is not associated with loss of hot strength. Unbalanced compositions are possible within the stated chemical ranges of this grade, and in this event some ferrite may be present in the austenite matrix. Such ferrite will transform to the brittle sigma phase if the alloy is held for more than short times around 1500°F (816°C) with consequent weakening at this temperature and embrittlement


S

Mo

0.04

0.51

Cr 24 28

Physical properties Modulus of elasticity, psi x 106 Equiaxed grains Columnar grains See Fig. 1 for variation with temperature Poisson’s ratio (See Fig. 1 for variation with temperature) 3 Density, lb/in Sp. Heat, Btu/lb.oF, at 70 oF Electrical resistivity, :S.m, at 70 oF Melting point, approximate oF Magnetic permeability Thermal conductivity Btu/(ft.h. oF) ________________ At 212 oF At 600 oF At 1000 oF At 1200 oF At 1400 oF At 1600 oF At 1800 oF At 2000 oF 2

7.9 9.8 11.8 12.9 14.2 15.72 17.12 18.62

Ni 18 22

Fe bal

27.0 20.0 0.30 0.280 0.12 0.90 2550 1.02


9.4 9.6 9.8 10.0

70 - 1800 oF 70 - 2000 oF 1200 - 1800 oF 1200 - 2000 oF

10.2 10.4 11.4 11.7

Estimated


Tensile strength, ksi Yield strength, 0.2% offset, ksi Elongation, in 2in., % Brinell hardness (HBW) Charpy keyhole, ft lbs 21.5

Representative values Aged 24h As cast at 1400 oF Furnace ______ cooled___

Minimum tensile requirements ASTM A297 ___________

75.0 50.0

85.0 50.0

65.0 35.0

17 170

10 190

10 -

Tensile ksi

Yield ksi


24.4 14.7 8.7 6.8 5.0

12 16 42 54 55

At elevated temperatures Representative values - short time________

1400 oF 37.5 1600 oF 23.3 o 1800 F 12.4 o 1900 F 9.1 o 2000 F 5.6 Creep rupture properties Representative values3 - long time

Limiting stress, 1% creep Stress to rupture in ksi, creep in, ksi stress, ksi hours rate 0.0001%/h 100,000 100 1,000 10,000 100,000 1400 oF 1600 oF 1800 oF 1900 oF 2000 oF 3 4

10.20 6.00 2.50 1.40 0.65

6.304 2.504 0.904 0.394 0.234

15.55 9.20 4.75 3.20 2.20

12.00 6.00 2.80 1.90 1.25

8.80 3.80 1.70 1.104 0.724

6.204 2.504 1.004 0.664 0.424


at room temperature. Formation of sigma phase in HK type alloy can occur directly from austenite in the range 1400 to 1600°F (760 to 871°C) particularly at the lower carbon level (0.20-0.30 percent), and for this reason a considerable scatter in properties at intermediate temperatures is observed for this grade. Silicon is helpful in conferring resistance of the alloy to carburization, but is normally held to 2.00 percent maximum because higher amounts promote sigma formation. Minimum creep rate and average rupture life are influenced strongly by variations in the carbon content of the HK alloy. Under the same conditions of temperature and load, alloys with higher carbon content have reduced creep rates and longer lives than those with lower carbon contents. Room temperature properties after aging at elevated temperatures are affected also: the higher the carbon the lower the residual ductility. For these reasons, within the chemical composition required by ASTM Specification A297 for the general HK alloy type shown in the Summary of Properties, three grades with narrower carbon ranges are recognized. These are the HK-30, HK-40 and HK-50 grades, in which the number following the alloy type designation indicates the midpoint of a +0.05 percent carbon range. In addition to the carbon limitation, a nitrogen range of 0.05 to 0.15 percent is specified for grades HK-40 and HK-50 in ASTM Specification A567. Nitrogen and molybdenum are not specified for grades HK-30 and HK-40 in ASTM Specification A351 but the manganese and silicon limits are lowered to 1.50 and 1.75 maximum, respectively, the chromium range is lowered to 23 to 27 percent and the nickel range is narrowed to 19 to 22 percent for each grade. An extended discussion of the influence of chemical composition variations on the mechanical properties of the HK type alloys is given in ALLOY CASTING BULLETIN No. 17, October 1961. Of the three grades, the HK-40 alloy of Specification A351 has become the most widely used. It has found extensive application in the petroleum and petro-chemical industries for process equipment operating at high temperatures. Castings of type HK alloy have good weldability and machining characteristics. Thermal expansion is about 40 percent greater than carbon steel or iron-chromium alloy types HC and HD, and heat conductivity is about 40 percent less. At room temperature, electrical resistance is about six times that of carbon steel, and the alloy is virtually non-magnetic. Heat Treatment Castings of type HK alloy are normally supplied in the as-cast condition. The alloy cannot be hardened by heat treatment. Applications The following lists of consuming industries, cast parts, and corrosive environments are useful as examples of typical applications where type HK alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries

Aircraft, Cement, Fertilizer, Heat Treating, Ore Refining, Petrochemical, Petroleum, Steel.

Castings Billet skids, brazing fixtures, calcining tubes, cement kiln nose segments, conveyor rolls, furnace door arches and lintels, heat treating trays and fixtures, pier caps, rabble arms and blades, radiant tubes, reformer tubes, retorts, rotating shafts, skid rails, sprockets, stack dampers. Environment Air, ammonia, carburizing gases, combustion gases, flue gases oxidizing and reducing, hydrogen, molten neutral salts. NOTE: Proper selection of an alloy for a specific high temperature service involves consideration of some or all of the following factors: 1) required life of the part, 2) range frequency and speed of temperature cycling, 3) atmosphere and contaminants therein, 4) complexity of casting design, and 5) further fabrication of the casting. The criteria that should be used as the bases of alloy comparison will depend on the factors enumerated, and the designer will be aided in his choice by providing the foundry with as much pertinent information as possible on intended operating conditions before reaching a definite decision to use this alloy.

The mechanical property and physical property data presented here in tabular and graphical form are representative for alloy HK. These data are neither average nor minimum values and should not be used for either specification or design purposes. Information on specification and/or design can be obtained from an appropriate technical association such as: ASTM, ASME, API, SAE and NACE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in HK alloy. Somewhat lighter sections are also feasible depending on casting design and pattern equipment. Good castability of this alloy permits designs involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allow for this alloy is 5/16 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type HK castings can be welded by metal-arc, inert-gas arc, and oxyacetylene gas methods. Metal-arc welding is generally preferred for high temperature applications of this alloy. Neither preweld nor postweld heat treating is required. Welding procedures utilizing SMAW, GMAW and GTAW techniques are described in this section. Machining Most machining operations can be performed satisfactorily on castings of HK alloy. It is important in all cases that the tool be kept continually entering into the metal to avoid work-hardening the surface. Slow feeds, deep cuts and powerful rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is suggested for use with high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast ASTM: A297(HK), A351(HK30, HK40), A567(HK40, HK50), A608(HK30, HK40), SAE 70310, AMS 5365 Wrought

AISI 310

Heat Resistant Type HL (UNS J94604)

Description Type HL is an iron-chromium-nickel alloy similar to type HK, but its higher chromium content gives this grade greater resistance to corrosion by hot gases, particularly those containing appreciable amounts of sulfur. Because essentially equivalent high temperature strength can be obtained with either the HK or HL grades, the improved corrosion resistance of the HL alloy makes it especially useful for severe service where excessive scaling must be avoided.


Heat Treatment Castings of type HL alloy are normally supplied in the as-cast condition. The alloy cannot be hardened by heat treatment.


Cr 28 32

Ni 18 22

At 212 oF At 600 oF At 1000 oF At 1200 oF At 1400 oF At 1600 oF At 1800 oF At 2000 oF 2 Estimated

8.2 10.2 12.2 13.4 14.7 16.3 17.7 19.3

Steel, Vitreous Enamel.

Castings Carrier fingers, enameling furnace fixtures, furnace skids for slabs and bars, radiant tubes, stack dampers. Air, flue gases.

NOTE: Proper selection of an alloy for a specific high temperature service involves consideration of some or all of

Fe bal

29.0 0.279 0.12 0.94 2600 1.01

70 - 1000 oF 70 - 1200 oF 70 - 1400 oF 70 - 1600 oF

9.2 9.4 9.6 9.7

70 - 1800 oF 70 - 2000 oF 1200 - 1600 oF 1200 - 1800 oF

9.9 10.1 10.5 10.7

Mechanical properties at room temperature Representative values As cast __________________

The following lists of consuming industries, cast parts, and corrosive environments are useful as examples of typical applications where type HL alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses.

Environment

0.5

1

Mean coefficient of Linear thermal expansion : in./(in. oF) ______________________________________

Applications

Industries

0.04

Mo


________________

The as-cast and aged microstructures of type HL alloy, as well as its physical properties and fabricating characteristics are about the same as those of the HK grade.

S


82.0 50.0 19 192

Minimum tensile requirements ASTM A297 ___________ 65.0 35.0 10 -


Tensile ksi

Yield ksi


1400 oF 1600 oF 1800 oF

50.0 30.4 18.7

-

-

Creep rupture properties Representative values3 - long time Limiting stress, ksi, creep rate 0.0001%/h 1400 oF 1600 oF 1800 oF 3

7.0 4.3 2.2

Stress to rupture, stress, ksi,hours 100 1,000 10,000 15.0 9.2 5.2

12.00 8.80 6.00 3.80 2.80 1.70


the following factors: 1) required life of the part, 2) range frequency and speed of temperature cycling, 3) atmosphere and contaminants therein, 4) complexity of casting design, and 5) further fabrication of the casting. The criteria that should be used as the bases of alloy comparison will depend on the factors enumerated, and the designer will be aided in his choice by providing the foundry with as much pertinent information as possible on intended operating conditions before reaching a definite decision to use this alloy. The mechanical property and physical property data presented here in tabular and graphical form are representative for alloy HL. These data are neither average nor minimum values and should not be used for either specification or design purposes. Information on specification and/or design can be obtained from an appropriate technical association such as: ASTM, ASME, API, SAE and NACE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in HL alloy. Somewhat lighter sections are also feasible depending on casting design and pattern equipment. Good castability of this alloy permits designs involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allow for this alloy is 5/16 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding The welding procedures outlined for Alloy HK are applicable for Alloy HL. Welding procedures utilizing SMAW, GMAW and GTAW techniques are described in this section. Machining Most machining operations can be performed satisfactorily on castings of HL alloy. It is important in all cases that the tool be kept continually entering into the metal to avoid workhardening the surface. Slow feeds, deep cuts and powerful rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is suggested for use with high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy Cast

ASTM: A297(HL), A608(HL30, HL40), SAE 70310A

Wrought

None

Heat Resistant Type HN (UNS J94213)

Description Type HN is an iron-chromium-nickel alloy containing sufficient chromium for good high temperature corrosion resistance and with a nickel content in excess of the chromium content. The alloy has properties somewhat similar to the much more widely used type HT alloy but with better ductility. It is used for highly stressed components in the 1800-2000°F (982 to 1093°C) temperature range. In several specialized applications, notably brazing fixtures, it has given satisfactory service at temperatures of 2000 to 2100°F (1093 to 1149°C). The alloy has an austenitic structure at all temperatures, and lies well within the stable austenite field. In the ascast condition carbide areas are present and additional fine carbides precipitate on aging. The alloy is not susceptible to sigma phase formation, nor is increased carbon content especially detrimental to ductility. Castings of type HN alloy have good machining and welding properties if proper techniques are employed. Heat Treatment Castings of type HN alloy are normally supplied in the as-cast condition. Applications The following lists of consuming industries, cast parts, and corrosive environments are useful as examples of typical applications where type HN alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Aircraft, Automotive, Petroleum, Petrochemical, Power.


Brazing fixtures, chain,

0.04

Mo 0.5

1

Cr 19 23


7.5 9.2 11.0 12.1 13.2 14.5 15.72 17.02

Ni 23 27

Fe bal

27.0 0.283 0.11 0.991 2500 1.10


9.3 9.5 9.7 9.9

70 - 1800 oF 70 - 2000 oF 1200 - 1800 oF 1200 - 2000 oF

10.1 10.2 11.0 11.1

Estimated



As cast ______


68.0 38.0 13 160

63.0 38.0 8 -


Tensile ksi

Yield ksi


1600 oF 1800 oF 1900 oF 2000 oF

20.250 11.950 8.500 6.165

14.50 9.675 5.500 4.925

37 51 53 55

Creep rupture properties Representative values3 - long time Limiting stress,ksi, creep rate 0.0001%/h o

1600 F 1800 oF 1900 oF 2000 oF 3

Castings

S

4

6.30 2.40 1.60 1.04

1% creep in, ksi 100,000

Stress to rupture in stress, ksi hours 100 1,000 10,000 100,000

3.004 1.104 0.454 0.174

11.0 5.6 4.6 2.9

7.40 3.40 2.10 1.25

4.80 2.10 0.964 0.524

3.204 1.304 0.444 0.224


furnace beams and parts, pier caps, radiant tubes and tube supports, sill plate brackets, torch nozzles, trays, tubes. Environment

Air, flue gases oxidizing and reducing.

NOTE: Proper selection of an alloy for a specific high temperature service involves consideration of some or all of the following factors: 1) required life of the part, 2) range frequency and speed of temperature cycling, 3) atmosphere and contaminants therein, 4) complexity of casting design, and 5) further fabrication of the casting. The criteria that should be used as the bases of alloy comparison will depend on the factors enumerated, and the designer will be aided in his choice by providing the foundry with as much pertinent information as possible on intended operating conditions before reaching a definite decision to use this alloy. The mechanical property and physical property data presented here in tabular and graphical form are representative for alloy HN. These data are neither average nor minimum values and should not be used for either specification or design purposes. Information on specification and/or design can be obtained from an appropriate technical association such as: ASTM, ASME, API, SAE and NACE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in HN alloy. Somewhat lighter sections are feasible depending on casting design and pattern equipment. Good castability of this alloy permits designs involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allow for this alloy is 5/16 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding The welding procedures outlined for Alloy HK are applicable for Alloy HN. Welding procedures utilizing SMAW, GMAW and GTAW techniques are described in this section. Machining Most machining operations can be performed satisfactorily on castings of HN alloy. It is important in all cases that the tool be kept continually entering into the metal to avoid workhardening the surface. Slow feeds, deep cuts and powerful rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Chips are tough and stringy; chip curlers and breaker tools are recommended. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is suggested for use with high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy Cast

ASTM: A297(HN), A608(HN40)

Wrought

None

Heat Resistant Type HP (UNS J95705)

Description Type HP is an iron-chromium-nickel alloy that is related to the HN and HT types but is higher in alloy content than either of those grades. It has the same chromium but more nickel than the HN type, and the same nickel but more chromium than the HT alloy. This combination of elements makes the HP composition resistant to both oxidizing and carburizing atmospheres at high temperatures. The alloy has good creeprupture properties in the 1800 to 2000°F (982 to 1093°C) temperature range comparable to, or better than, the HK-40 and HN alloy types. The HP alloys have many modifications, to the extent that unmodified grades form a very small proportion of “HP” alloys supplied to purchasers. There are essentially two groups of alloy modifications. The first relies on the addition of such elements as Nb and W to improve creep rupture properties and the second makes a further addition of microalloys such as Ti. These microalloyed grades have even greater rupture properties than the first stage of modification. Within this group of alloy types the Si levels may be increased for applications in carburizing environments. The addition of Si usually causes a drop in the creep rupture properties when compared to the grades not used in carburizing applications. Because of its high nickel content, the alloy is not susceptible to sigma phase formation. The microstructure consists of massive primary carbides in an austenitic matrix together with fine carbides which are precipitated within the austenite grains after aging at elevated temperature.


Thermal conductivity Btu/(ft.h. oF) ________________ At 212 oF At 600 oF At 1000 oF At 1200 oF At 1400 oF At 1600 oF At 1800 oF At 2000 oF 2

0.04

0.51

Cr 24 28

7.5 9.22 11.02 12.12 13.22 14.52 15.72 17.02

Ni 33 37

Fe bal

27.0 0.3 0.284 0.11 1.022 2450 1.02 - 1.25

Mean coefficient of Linear thermal expansion : in./(in. oF) ______________________________________ 70 - 1000 oF 70 - 1200 oF 70 - 1400 oF 70 - 1600 oF 70 - 1800 oF

9.22 9.5 9.82 10.02 10.32

70 - 1800 oF 70 - 2000 oF 1200 - 1800 oF 1200 - 2000 oF 1600 - 2000 oF

10.62 11.42 11.92 12.22 13.12

Estimated


Tensile strength, ksi Yield strength, 0.2% offset, ksi Elongation, in 2in., %

As cast _______


71.0 40.0 11.5

62.5 34.0 4.5


Tensile ksi

Yield ksi


1400 oF 1600 oF 1800 oF 2000 oF

43.0 26.0 14.5 7.5

29.0 17.5 11.0 6.2

15 27 46 69

Creep rupture properties Representative values3 - long time Limiting stress,ksi, creep rate 0.0001%/h o

Castings of type HP alloy are normally supplied in the as-cast condition.

Mo

Physical properties Modulus of elasticity, psi x 106 Poisson’s ratio Density, lb/in3 Sp. Heat, Btu/lb.oF, at 70 oF Electrical resistivity, :S.m, at 70 oF Melting point, approximate oF Magnetic permeability

Castings of type HP alloy have good machining and welding properties similar to the HT type. Heat Treatment

S

1600 F 5.8 1800 oF 2.8 2000 oF 1.0 3 4

1% creep in, ksi 100,000

Stress to rupture in stress, ksi hours 100 1,000 10,000 100,000

4.9 2.1 0.4

10.0 5.9 2.8

7.5 3.6 1.5

5.10 2.20 0.60

3.304 1.104 0.254


Applications The following lists of consuming industries, cast parts, and corrosive environments are useful as examples of typical applications where type HP alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries

Heat Treating, Petrochemical, Petroleum.

Castings

Ethylene pyrolysis heaters, heat treat fixtures, radiant tubes, refinery tubes.

Environment

Air, carburizing atmospheres, flue gases oxidizing and reducing.

NOTE: Proper selection of an alloy for a specific high temperature service involves consideration of some or all of the following factors: 1) required life of the part, 2) range and speed of temperature cycling, 3) atmosphere and contaminants therein, 4) complexity of casting design, and 5) further fabrication of the casting. The criteria that should be used as the bases of alloy comparison will depend on the factors enumerated, and the designer will be aided in his choice by providing the foundry with as much pertinent information as possible on intended operating conditions before reaching a definite decision to use this alloy. The mechanical property and physical property data presented here in tabular and graphical form are representative for alloy HP. These data are neither average nor minimum values and should not be used for either specification or design purposes. Information on specification and/or design can be obtained from an appropriate technical association such as: ASTM, ASME, API, SAE and NACE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in HP alloy. Somewhat lighter sections are also feasible depending on casting design and pattern equipment. Good castability of this alloy permits designs involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allow for this alloy is 5/16 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type HP castings can be welded by metal-arc, inert-gas arc, and oxyacetylene gas methods. Electric arc processes are most widely used. Neither preweld nor postweld heat treating is required.The welding procedures outlined for Alloy HK are applicable for Alloy HP. Welding procedures utilizing SMAW, GMAW and GTAW techniques are described in this section. Machining Most machining operations can be performed satisfactorily on castings of HP alloy. It is important in all cases that the tool be kept continually entering into the metal to avoid work-hardening the surface. Slow feeds, deep cuts, and powerful rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Chips are tough and stringy; chip curlers and breaker tools are recommended. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is suggested for use with high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide

tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy Cast

ASTM: 297(HP)

Wrought

None

Heat Resistant Type HT (UNS J94605)

Description Type HT is an iron-chromium-nickel alloy containing about equal amounts of iron and alloying elements. The high nickel content makes this grade useful in resisting the thermal shock of rapid heating and cooling. In addition the alloy is resistant at high temperature to oxidation and carburization, and has good strength at heat treating temperatures. Except in high sulfur gases, it performs satisfactorily up to 2100°F (1149°C) in oxidizing atmospheres and up to 2000°F (1093°C) in reducing atmospheres provided limiting creep stress values are not exceeded. This grade is widely used for general heat resistant applications in highly stressed parts. The alloy has an austenitic structure containing varying amounts of carbides depending on the carbon content and thermal history. In the as-cast condition large carbide areas are present at the grain boundaries, but fine carbides precipitate within the grains after exposure at service temperatures with subsequent decrease in room temperature ductility. Increased carbon content does not significantly affect the high temperature ductility of the alloy; this characteristic makes it especially useful for carburizing fixtures or containers. Additional protection against carburization is obtained with silicon contents above about 1.6%, but at some sacrifice of hot strength. Castings of type HT alloy have good machining and welding properties if proper techniques are employed. Thermal expansion is about one-third greater than carbon steel or ironchromium alloy types HC or HD, and about ten percent less than ironchromium-nickel alloy types HF and HH. Electrical resistance is over six times that of carbon steel and is characterized by a low temperature coefficient of resistivity (0.00017 per °F, 70-930°F) (0.000306 per °C, 21-499°C). The composition of type


S

Mo

0.04

0.51

Cr 15 19

Ni 33 37


7.0 8.9 10.8 11.9 12.9 14.0 15.32 16.32

Fe bal

27.0 0.286 0.11 1.0 2450 1.10 - 2.00

Mean coefficient of Linear thermal expansion : in./(in. oF) ______________________________________ 68 - 200 oF 68 - 400 oF 68 - 600 oF 68 - 800 oF 68 - 1000 oF 68 - 1200 oF

7.90 8.14 8.37 8.61 8.85 9.09

68 - 1800 oF 68 - 2000 oF 68 - 1800 oF 68 - 2000 oF 1200 - 1600 oF 1200 - 1800 oF

9.33 9.56 9.80 10.04 10.75 11.00

Estimated


Tensile strength, ksi Yield strength, 0.2% offset, ksi Elongation, in 2in., % Brinell hardness (HBW) Charpy keyhole ft.lbs



70.0 40.0

75.0 45.0

65.0 -

10 180 4

5 200 -

-

Tensile ksi

Yield ksi


28.0 26.0 15.0 8.0 -

5 10 26 28 -

4


1200 oF 42.4 1400 oF 35.0 o 1600 F 18.8 1800 oF 11.0 2000 oF 6.0 Creep rupture properties 3 Representative values - long time Limiting stress, ksi, creep rate 0.0001%/h o

100

Stress to rupture in stress, ksi hours 1,000 10,000

100,000

1400 F 8.00 16.0 12.0 8.4 5.604 1600 oF 4.50 8.9 5.8 3.7 2.404 1800 oF 2.00 4.4 2.7 1.7 1.054 1900 oF 0.50 2.1 1.3 0.15 2000 oF 3 For constant temperature, for cyclic temperature lower values would apply 4 Extrapolated

HT is such that the magnetic transformation of austenite occurs near room temperature. Minor shifts in constituents after service at high temperature or exposure to carburizing atmospheres may change as-cast magnetic permeability values considerably. Heat treatment Castings of type HT alloy are normally supplied in the as-cast condition. The alloy cannot be hardened by heat treatment, but for applications involving thermal fatigue from repeated rapid heating and cooling, improved performance may be obtained by heating castings at 1900°F (1038°C) for 12 hours followed by furnace cooling prior to placing in service. Applications The following lists of consuming industries, cast parts, and corrosive environments are useful as examples of typical applications where type HT alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Enamel.

Aluminum, Cement, Glass, Industrial Furnace, Heat Treating, Magnesium, Steel, Vitreous

Castings Air ducts, brazing trays, carburizing containers, chain, cyanide pots, dampers, dippers, door frames, enameling bars and supports, fan blades, feed screws, gear spacers, glass molds, glass rolls, hearth plates, heat treating fixtures and trays, idler drums, kiln nose rings, lead pots, malleablizing baskets, muffles, oil burner nozzles, point bars, radiant tubes, resistor guides, retorts, roller rails, rolling mill guides, salt pots, tube supports. Environment

Air carburizing gas, flue gases oxidizing and reducing, molten metals, salts.

NOTE: Proper selection of an alloy for a specific high temperature service involves consideration of some or all of the following factors: 1) required life of the part, 2) range frequency and speed of temperature cycling, 3) atmosphere and contaminants therein, 4) complexity of casting design, and 5) further fabrication of the casting. The criteria that should be used as the bases of alloy comparison will depend on the factors enumerated, and the designer will be aided in his choice by providing the foundry with as much pertinent information as possible on intended operating conditions before reaching a definite decision to use this alloy. The mechanical property and physical property data presented here in tabular and graphical form are representative for alloy HT. These data are neither average nor minimum values and should not be used for either specification or design purposes. Information on specification and/or design can be obtained from an appropriate technical association such as: ASTM, ASME, API, SAE and NACE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in HT alloy. Somewhat lighter sections are also feasible depending on casting design and pattern equipment. Good castability of this alloy permits designs involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allow for this alloy is 5/16 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type HT castings can be welded by metal-arc, inert gas-arc, and oxyacetylene gas methods.

Electric arc processes are most widely used, but satisfactory welds are also made with the oxyacetylene flame. The optimum balance between weld soundness and ductility is obtained if the Si to C ratio in the weld deposit is about the same as in the cast alloy, i.e. about 2:1. Neither preweld nor postweld heat treating is required. Welding procedures utilizing SMAW, GMAW and GTAW techniques are described in this section. Machining Most machining operations can be performed satisfactorily on castings of HT alloy. It is important in all cases that the tool be kept continually entering into the metal to avoid work-hardening the surface. Slow feeds, deep cuts and powerful rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Chips are tough and stringy; chip curlers and breaker tools are recommended. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is suggested for use with high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy The American Iron and Steel Institute wrought alloy designation is listed only for the convenience of those who want to determine corresponding wrought and cast grades. Because the cast chemical composition ranges are not the same as the wrought composition ranges, buyers should use cast alloy designations for proper identification of castings. Cast

ASTM: A297(HT), A608(HT50), SAE 70330

Wrought

AISI 330

Heat Resistant Type HU (UNS J95405)

Description Type HU is an iron-chromium-nickel alloy similar to type HT, but its higher chromium and nickel contents give this grade greater resistance to corrosion by either oxidizing or reducing hot gases, particularly those containing appreciable amounts of sulfur. High temperature strength, resistance to thermal fatigue, and resistance to carburization of the alloy are essentially the same as shown by the HT type; hence, its improved corrosion resistance makes the HU type especially suited for severe service conditions involving high stress and rapid thermal cycling. The as-cast and aged microstructures of type HU alloy, as well as its physical properties and fabricating characteristics are about the same as those of the HT grade.


S

Mo

0.04

0.51

Cr 17 21


7.0 8.9 10.8 11.9 12.9 14.0 15.32 16.32

Ni 37 41

Fe bal

27.0 0.290 0.11 1.05 2450 1.10 - 2.00

Mean coefficient of Linear thermal expansion : in./(in. oF) ______________________________________ 70 70 70 70 -

200 oF 400 oF 600 oF 800 oF

8.8 9.0 9.2 9.4

70 - 1800 oF 70 - 2000 oF 1200 - 1800 oF 1200 - 2000 oF

9.6 9.7 10.5 10.6

Estimated


Heat Treatment Castings of type HU alloy are normally supplied in the as-cast condition. The alloy cannot be hardened by heat treatment, but for applications involving thermal fatigue from repeated rapid heating and cooling, improved performance may be obtained by heating castings at 1900°F (1038°C) for 12 hours followed by furnace cooling prior to placing in service. Applications The following lists of consuming industries, cast parts, and corrosive environments are useful as examples of typical applications where type HU alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses.



70.0 40.0

73.0 43.0

65.0 -

9 170 4

5 190 -

-

Representative values - short time________

Tensile ksi

Yield ksi


1400 oF 1600 oF 1800 oF

40.0 19.6 10.0

6.2

20 28

Tensile strength, ksi Yield strength, 0.2% offset, ksi Elongation, in 2in., % Brinell hardness (HBW) Charpy keyhole ft.lbs At elevated temperatures

Creep rupture properties Representative values3 - long time Limiting stress, ksi, creep rate 0.0001%/h o

Industries Steel.

Aluminum, Heat Treating,

Castings Articulated trays, burner tubes, carburizing retorts, conveyor

4

1400 F 1600 oF 1800 oF 2000 oF 3

8.5 5.0 2.2 0.6

Stress to rupture in stress, ksi hours 100 1,000

10,000

15.0 8.0 4.5 -

3.3 1.8 -

5.2 2.9 -


screws and chains, cyanide pots, dipping baskets, furnace rolls, lead pots, muffles, pouring spouts, radiant tubes, resistor guides. Environment Air, carburizing gases, combustion gases, flue gases oxidizing and reducing, molten cyanide, molten lead. NOTE: Proper selection of an alloy for a specific high temperature service involves consideration of some or all of the following factors: 1) required life of the part, 2) range frequency and speed of temperature cycling, 3) atmosphere and contaminants therein, 4) complexity of casting design, and 5) further fabrication of the casting. The criteria that should be used as the bases of alloy comparison will depend on the factors enumerated, and the designer will be aided in his choice by providing the foundry with as much pertinent information as possible on intended operating conditions before reaching a definite decision to use this alloy. The mechanical property and physical property data presented here in tabular and graphical form are representative for alloy HU. These data are neither average nor minimum values and should not be used for either specification or design purposes. Information on specification and/or design can be obtained from an appropriate technical association such as: ASTM, ASME, API, SAE and NACE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in HU alloy. Somewhat lighter sections are also feasible depending on casting design and pattern equipment. Good castability of this alloy permits designs involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allow for this alloy is 5/16 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type HU castings can be welded by metal-arc, inert gas-arc, and oxyacetylene gas methods. Electric arc processes are most widely used, but satisfactory welds are also made with the oxyacetylene flame. The optimum balance between weld soundness and ductility is obtained if the Si to C ratio in the weld deposit is about the same as in the cast alloy, i.e. about 2:1. Neither preweld nor postweld heat treating is required. Welding procedures utilizing SMAW, GMAW and GTAW techniques are described in this section. Machining Most machining operations can be performed satisfactorily on castings of HT alloy. It is important in all cases that the tool be kept continually entering into the metal to avoid work-hardening the surface. Slow feeds, deep cuts and powerful rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Chips are tough and stringy; chip curlers and breaker tools are recommended. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is suggested for use with high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26.

Casting designations, specifications, and corresponding wrought alloy Cast

ASTM: A297(HU), A608(HU50), SAE 70331

Wrought

None

Heat Resistant Type HW

Description Type HW is an iron-chromium-nickel alloy in which nickel is the predominant element. The high nickel content contributes toward the excellent resistance of the alloy to carburization and also makes this grade especially useful in applications where wide and rapid temperature fluctuations are encountered. In addition, the alloy is resistant at high temperature to oxidation and, although not as strong as the HT type, has good strength at heat treating temperatures. It performs satisfactorily up to about 2050°F (1121°C) in strongly oxidizing atmospheres and up to 1900°F (1038°C) in oxidizing or reducing products of combustion provided that sulfur is not present in the gas. The generally adherent nature of its oxide scale makes the HW type alloy suitable for enameling furnace service where even small flecks of dislodged scale could ruin the work in process. This grade is widely used for intricate heat treating fixtures that are quenched with the load, and for many other applications involving thermal shock and steep temperature gradients under highly stressed conditions. The alloy has an austenitic structure containing varying amounts of carbides depending on the carbon content and thermal history. In the as-cast condition the microstructure consists of a continuous interdendritic network of massive and elongated eutectic carbides. After aging at service temperatures, the austenitic matrix becomes uniformly peppered with small carbide particles except in the immediate vicinity of the eutectic carbides. This change is structure is accompanied by an increase in room temperature strength without change in ductility. The alloy has good high temperature ductility that is not appreciably affected by increased carbon content resulting from carburizing service.


S

Mo

0.04

0.51

Cr 10 14


7.2 9.0 11.1 12.2 13.3 14.5 15.72 17.02

Ni 58 62

Fe bal

25.0 0.294 0.11 1.12 2350 16.0

Mean coefficient of Linear thermal expansion : in./(in. oF) ______________________________________ 68 - 200 oF 68 - 400 oF 68 - 600 oF 68 - 800 oF 68 - 1000 oF 68 - 1200 oF

7.00 7.22 7.45 7.70 7.95 8.20

68 - 1800 oF 68 - 2000 oF 68 - 1800 oF 68 - 2000 oF 1200 - 1600 oF 1200 - 1800 oF

8.47 8.74 9.01 9.28 10.00 10.33

Estimated



68.0 36.0

84.0 52.0

60.0 -

4 185

4 205

-


Tensile ksi

Yield ksi


1400 oF 1600 oF 1800 oF

32.0 19.0 10.0

23.0 15.0 8.0

40


Creep rupture properties Representative values3 - long time Limiting stress, ksi, creep rate 0.0001%/h o

1400 F 1600 oF 1800 oF 3

6.0 3.0 1.4

Stress to rupture in stress, ksi hours 10 100

1,000

16.0 8.2 4.3

7.8 4.5 2.6

10.0 6.0 3.6


Castings of type HW alloy have good machining and welding properties if proper techniques are employed. Thermal expansion is about 20 percent greater than carbon steel or iron-chromium alloy types HC or HD, but about ten percent less than the iron-chromium-nickel alloy type HT. Electrical resistance is roughly seven times that of carbon steel and is characterized by a very low temperature coefficient of resistivity (0.000095 per °F, 70-212°F) (0.000171 per °C, 21-100°C) so that from room temperature to 1800°F (982°C) there is an increase of less than 10 percent in resistance. Thus, the alloy is useful for cast electric heating elements. At room temperature the HW type alloy is magnetic both as-cast and after aging at elevated temperature. Heat Treatment Castings of type HW alloy are normally supplied in the as-cast condition. Applications The following lists of consuming industries, cast parts, and corrosive environments are useful as examples of typical applications where type HW alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries

Heat Treating, Vitreous Enamel.

Castings Cyanide pots, electric heating elements, enameling tools, gas retorts, hardening fixtures, hearth plates, lead pots, muffles. Environment

Air, carburizing gases, combustion gases, flue gases, molten cyanide, molten lead.

NOTE: Proper selection of an alloy for a specific high temperature service involves consideration of some or all of the following factors: 1) required life of the part, 2) range frequency and speed of temperature cycling, 3) atmosphere and contaminants therein, 4) complexity of casting design, and 5) further fabrication of the casting. The criteria that should be used as the bases of alloy comparison will depend on the factors enumerated, and the designer will be aided in his choice by providing the foundry with as much pertinent information as possible on intended operating conditions before reaching a definite decision to use this alloy. The mechanical property and physical property data presented here in tabular and graphical form are representative for alloy HW. These data are neither average nor minimum values and should not be used for either specification or design purposes. Information on specification and/or design can be obtained from an appropriate technical association such as: ASTM, ASME, API, SAE and NACE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in HW alloy. Somewhat lighter sections are also feasible depending on casting design and pattern equipment. Good castability of this alloy permits designs involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allow for this alloy is 9/32 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type HW castings can be welded by metal-arc, inert gas-arc, and oxyacetylene gas methods. Electric arc processes are most widely used, but satisfactory welds are also made with the oxyacetylene flame. Bare Inconel wire and stainless flux should be used for gas welding, and the flame should be adjusted to very rich in acetylene. Neither preweld nor postweld heating is required.

Welding procedure utilizing SMAW technique is described in this section. Machining Most machining operations can be performed satisfactorily on castings of HW alloy. It is important in all cases that the tool be kept continually entering into the metal to avoid work-hardening the surface. Slow feeds, deep cuts and powerful rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Chips are tough and stringy; chip curlers and breaker tools are recommended. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is suggested for use with high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26. Casting designations, specifications, and corresponding wrought alloy

Cast

ASTM: A297(HW), A608(HW50), SAE 70334

Wrought

None

Heat Resistant Type HX

Description Type HX is an iron-chromium-nickel alloy similar to type HW, but containing more nickel and chromium. The increased chromium content confers substantially improved resistance to hot gas corrosion, even in the presence of some sulfur, which permits this grade to be employed for severe service applications at temperatures up to 2100°F (1149°C). High temperature strength, resistance to thermal fatigue, and resistance to carburization of the alloy are essentially the same as shown by the HW type; hence, it is suitable for the same general applications in situations where corrosion must be minimized. The as-cast and aged microstructures of type HX alloy, as well as it physical properties and fabricating characteristics are about the same as those of the HW grade. A minor differences that the HX type is only slightly magnetic.


Applications The following lists of consuming industries, cast parts, and corrosive environments are useful as examples of typical applications where type HX alloy has been employed successfully; they are not comprehensive, nor are they intended as guides to alloy selection for specific end uses. Industries Heat Treating, Steel, Vitreous Enamel. Castings Autoclaves, brazing furnace rails and doors, calciner tubes, carburizing boxes, cyanide pots, enameling tools, heating elements, hearth plates, heat treating trays and

0.04

Mo 0.5

1

Cr 15 19


7.22 9.02 11.12 12.22 13.32 14.52 15.72 17.02

Ni 64 68

Fe bal

25.0 0.294 0.11 1.16 2350 2.0

Mean coefficient of Linear thermal expansion : in./(in. oF) ______________________________________ 70 70 70 70 -

200 oF 400 oF 600 oF 800 oF

7.8 8.1 8.5 8.8

70 - 1800 oF 70 - 2000 oF 1200 - 1600 oF 1200 - 1800 oF

9.2 9.5 10.7 11.3

Estimated



65.0 36.0

73.0 44.0

60.0 -

9 176

9 185

-


Tensile ksi

Yield ksi


1200 oF 1600 oF 1800 oF

45.0 20.5 10.7

20.0 17.5 8.0

8 48 40

Heat Treatment Castings of type HX alloy are normally supplied in the as-cast condition.

S


Creep rupture properties Representative values3 - long time Limiting stress, ksi, creep rate 0.0001%/h

Stress to rupture in stress, ksi hours 10 100

1,000

1400 oF 6.4 18.0 13.0 3.2 10.0 6.7 4.0 1600 oF 1800 oF 1.6 5.4 3.5 2.2 o 0.6 2.5 0.9 2000 F 3 For constant temperature, for cyclic temperature lower values would apply

fixtures, lead pots, muffles, retorts, roller hearths, salt bath electrodes, salt pots, shaker hearths. Environment Air, carburizing gases, combustion gases, flue gases, hydrogen, molten cyanide, molten lead, molten neutral salts. NOTE: Proper selection of an alloy for a specific high temperature service involves consideration of some or all of the following factors: 1) required life of the part, 2) range frequency and speed of temperature cycling, 3) atmosphere and contaminants therein, 4) complexity of casting design, and 5) further fabrication of the casting. The criteria that should be used as the bases of alloy comparison will depend on the factors enumerated, and the designer will be aided in his choice by providing the foundry with as much pertinent information as possible on intended operating conditions before reaching a definite decision to use this alloy. The mechanical property and physical property data presented here in tabular and graphical form are representative for alloy HX. These data are neither average nor minimum values and should not be used for either specification or design purposes. Information on specification and/or design can be obtained from an appropriate technical association such as: ASTM, ASME, API, SAE and NACE. Design Considerations Section thicknesses from 3/16 inch up can be cast satisfactorily in HX alloy. Somewhat lighter sections are also feasible depending on casting design and pattern equipment. Good castability of this alloy permits designs involving intricate shapes. Drastic changes in section should be avoided, however, and uniform thickness should be maintained as far as possible. This applies to the casting as cast; i.e., including finish allowance of 1/8 inch or more on surfaces to be machined. Normally used patternmakers' shrinkage allow for this alloy is 9/32 inch per foot. Fabricating Considerations Dimensional tolerances for rough castings are influenced by the quality of pattern equipment provided. In general, overall dimensions and locations of cored holes can be held to 1/16 inch per foot. Welding Type HX castings can be welded by metal-arc, inert gas-arc, and oxyacetylene gas methods. Electric arc processes are most widely used, but satisfactory welds are also made with the oxyacetylene flame. Bare Inconel wire and stainless flux should be used for gas welding, and the flame should be adjusted to very rich in acetylene. Neither preweld nor postweld heating is required. Welding procedures utilizing SMAW, and GTAW techniques are described in this section. Machining Most machining operations can be performed satisfactorily on castings of HW alloy. It is important in all cases that the tool be kept continually entering into the metal to avoid work-hardening the surface. Slow feeds, deep cuts and powerful rigid machines are necessary for best results. Work should be firmly mounted and supported, and tool mountings should provide maximum stiffness. Both high speed steel and carbide tools may be used successfully. Chips are tough and stringy; chip curlers and breaker tools are recommended. Good lubrication and cooling are essential. The low thermal conductivity of the alloy makes it most important to have the cutting fluid flood both the tool and the work. Sulfo-chlorinated petroleum oil containing active sulfur and about 8 to 10 percent fatty oil is suggested for use with high speed steel tools. Water-soluble cutting fluids are primarily coolants and are most useful for high speed operation with carbide tools. Information on the procedures for specific machining operations is contained in SFSA Steel Casings Handbook, 6th Edition, Chapter 26.

Casting designations, specifications, and corresponding wrought alloy

Cast

ASTM: A297(HX), A608(HX50), SAE 70335

Wrought

None

Steel Castings Handbook

Recommend Documents