GMW3032

WORLDWIDE ENGINEERING STANDARDS

Material Specification

GMW3032

High Strength Sheet Steel, 180 MPa through 700 MPa Yield Strengths

1 Scope This standard covers the requirements for continuous cast sheet steel with specified minimum yield strengths from 180 MPa through 700 MPa and is applicable to uncoated and coated, cold (CR) or hot rolled (HR) low carbon, solid solution strengthened, bake hardenable (BH), and interstitial free (IF) or high strength low alloy (HSLA) substrates with good formability. Continuously hot or cold rolled flat products shall be supplied as coils or sheet. Hot rolled flat products are usually supplied in thicknesses >1.75 mm. These flat products are used for cold forming and for manufacturing of welded tubes. Cold or hot rolled flat products with the appropriate surface type and surface finish are suitable for the application of surface coatings (metallic hot dipping, electrolytic plating, hot spray painting, organic coatings and/or other coatings). This specification does not apply to steel for case hardening and cold reduced, work hardened strips. Additional requirements or agreements shall be specified by regional GM business units, e.g., GM North America (GMNA), GM Europe (GME), GM Brazil (GMB), and GM Korea (GMK). 1.1 Material Description. Description. The material designation is defined by the GM Worldwide (GMW) base metal specification number, steel product type, minimum yield strength, and finish type. The steel product type is designated by CR for cold rolled products, or HR for hot rolled products. Microstructure free of banding, which is caused by the interdendritic segregation of manganese during solidification, is specified for hot rolled HSLA inclusion-controlled grades that are used for chassis applications. A numeral, (180, 210, 240, etc.,) will designate the minimum yield strength level in MPa (Megapascals). A designation of steel type shall be added to BH 2, solid solution strengthened grades Re-phosphorized and Interstitial Free (P and IF), structural automotive (SA) and high strength low alloy (LA) steels as shown in Section 8. An “F” designation may be added on engineering and/or manufacturing documents following an LA steel type to specify the steel as inclusion- controlled. A “B” designation is specified for hot rolled LA “F” type grades which need to be free of microstructural banding. Anisotropy Index for banding free grades is listed under Appendix C. The steel grades will correspond to the chemical and mechanical requirements as shown in Table 1 through Table 5. The finish type, Pan alpha character, will designate the finish as E (exposed) or U (unexposed). In addition, products which are not coated shall have the word “Uncoated” Uncoated” added to the call-out call-out after the steel type, but before the finish designation. A special requirement for temper rolling may be required and shall be specified with a “T” designation. The descriptive items in this section (1.1) are used together to form the coding system. Examples of the coding system for engineering part drawings and manufacturing engineering documents are shown in Section 8. 1.1.1 Material Identification. See Appendix A, Table A1. 1.2 Symbols. Not Symbols. Not applicable. 1.3 Applicability. Applicability. Typical applications are coated or uncoated sheet metal parts consisting of high strength sheet steel with specified minimum yield strengths from 180 MPa through 700 MPa.

© Copyright 2014 General Motors Company All Rights Reserved

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Copyright General Motors Company Provided by IHS under license with General Motors Company No reproduction or networking permitted without license from IHS

Order Number: W1978614

Sold to:DYTECH BRASIL IND. COM. LTDA [700171100585] - CAMILA.FERREIRA@DYTECHAUTO Not for Resale,2017-05-05 13:45:53 UTC

GM WORLDWIDE ENGINEERING STANDARDS

GMW3032

2 References Note: Only the latest approved standards are applicable unless otherwise specified. 2.1 External Standards/Specifications. AS 1391 ASTM A370 ASTM A751 ASTM E45

ASTM E112 ASTM E1268 EN 10049 EN 10247

ISO 6892 ISO 7438 ISO 14284 JIS G 3113

JIS Z 2201

GMW15056 GMW15282 GMW15425 GMW16066 GMW16086 GMW16170 GMW16546

GMW16549 GMW16656 GMW16823

2.2 GM Standards/Specifications. GMW8 GMW11 GMW3005 GMW3011 GMW3059 GMW3224 GMW3335

GMW14057 GMW14058 GMW14700 GMW14704 GMW14729 GMW14829 GMW14872

2.3 Additional References. 

GWS-5A.



Statement of Requirements (SOR).



TMC003 Material Safety Data Sheet guidance documents (available at www.gmsupplypower.com) at www.gmsupplypower.com)..



[email protected].

3 Requirements This section defines specific requirements for material on delivery, processing, performance and other stages during life cycle. Deviations required for individual GM business units are listed in the Deviation Section at the end of this specification and shall be agreed between Purchasing and supplier. 3.1 Requirements on Test Specimens. Not applicable. 3.2 Requirements on Delivery. 3.2.1 Chemical Requirements. 3.2.1.1 Base Metal. Base metal composition based on product (coil or sheet/blanks) analysis determined per ASTM A751 shall conform to the requirements of Table 1 and Table 2. When end-product (coil/blank) test results are not available, heat analysis may be used. Chemical composition on the end product is the referee method. 3.2.1.2 Surface Treatment. Products coated with a designated lubricant (e.g., mill oil or pre-lube) shall comply with GMW16546 and GMW16656 and/or be approved by the local business unit. 3.2.2 Mechanical Requirements. Products supplied to this specification shall meet the mechanical properties as specified in Table 3 through Table 6. The mechanical test methods to be used are defined in GMW3335 using the appropriate tensile test piece required by the specific region. Tests shall be performed using samples per ISO 6892 Type T ype I, 50 mm gage length ASTM (ASTM International) type sample, sam ple, ISO 6892 Type II (80 mm gage length) German Institute for Standardization (DIN) type sample or JIS Z 2201 (No. 5 test piece). Plastic strain ratio r m (r-bar) shall be determined at 20% strain. When uniform elongation is <20%, plastic strain values shall be determined at the maximum of uniform elongation. The specific strain level shall be reported with all test results. Strain hardening exponent “n” and strength coefficient “K” value shall be determined at 10% to 20% strain, or at 10% to end of uniform elongation when uniform elongation is <20% unless minimum n-value is <0.12. In these cases, the strain hardening exponent must be determined at 6% to end of uniform elongation. The specific strain range shall be reported with all test results. For tensile tests conducted to ISO 6892, only longitudinal test samples should be used (except for r m value). Conformance to the r m (r-bar) requirement shall be verified at the time of approval and at the time of the initial production shipment, unless otherwise required by the local materials engineering or manufacturing department. © Copyright 2014 General Motors Company All Rights Reserved

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GMW3032

3.2.2.1 Mechanical Property Requirements of Solid Solution Strengthened and Bake Hardenable Grades. Mechanical property requirements of solid solution strengthened (P and IF) and (BH 2) cold reduced, uncoated and coated sheet steel grades are based on the minimum as-received yield strength (180 MPa, 210 MPa, 240 MPa, 270 MPa and 300 MPa) as shown in Table 3. Bake hardenable steels have the additional requirement of a bake hardening index (BHI). All bake hardenable grades shall attain an increase in yield strength of 30 MPa minimum in lower yield strength (longitudinal direction and exclusive of work hardening) after 2% tensile strain and baking at +170 °C for 20 minutes. Mechanical properties for the B2 (BH 2 grades) are shown in Table 3. Bake Hardening and Work Hardening Indices shall be determined as detailed in Appendix B, Figure B1 and Figure B2. The actual or measured bake hardening response for a production part depends on a number of factors that must be considered. The amount of strain, the direction of strain relative to the test direction, the actual part temperature/time in the paint bake ovens, etc., may all impact the observed bake hardening response. Note: The bake hardening index in this specification is a parameter that characterizes the general bake hardening response of steel. 3.2.2.2 Bend Test Requirements for Structural Automotive Grades. Testing shall be performed to ISO 7438, bend test on two (2) low friction mounted test rollers and a punch, transverse to the rolling direction. Structural Automotive (SA) grades must meet the bending radii as specified in Table 6 for a bending angle of 180 degrees. After the test, the samples shall be free from visual cracking. 3.2.3 Physical Requirements. 3.2.3.1 Material Thickness and Tolerance. The detailed engineering part drawing/electronic math file will specify the material thickness and tolerance. The tolerance requirements for various thicknesses and strength levels are listed in GMW3224. 3.2.3.2 Surface Requirements. 3.2.3.2.1 Surface Texture. Specific requirements for the surface texture for each region are detailed in the Deviations Section at the end of this specification. 3.2.3.2.2 Surface Quality. The steel shall be free from surface defects as negotiated between purchaser and supplier. For unexposed (U) surface, defects such as pores, slight indentations, small marks, minor scratches, and slight coloring, which do not affect formability or the application of surface coatings, are allowed. Exposed (E) surfaces shall be free of defects which might affect the uniform appearance of quality paint or an electrolytic coating, electrodeposited primer, cathodic e-coat (ELPO). Certain applications require that both surfaces of the steel be of exposed surface quality. A special requirement for temper rolling may be required and shall be specified with a (T) designation. Other surfaces shall conform at least to unexposed surface quality (U). Detailed requirements will be issued by the responsible formability analysis organization (e.g., GMNA Manufacturing Engineering Material Parts Specification (MPS) sheet, GM responsible manufacturing, or metallurgical engineering document etc. 3.2.3.2.3 Roughness of Skin Passed Products. The requirements for roughness average (Ra) and roughness peak count (RPc) should be per GMW16823. 3.2.3.2.4 Surface of Hot Rolled Products without Special Requirements on the Surface Quality. Uncoated hot rolled products shall be supplied in a pickled (descaled) and oiled condition to ensure an adequate processability and a good adhesion of applied coatings. These products are usually not skin passed, but at the supplier’s choice or by agreement , the products can be supplied in a slightly skin passed condition or with agreement by GM. 3.2.3.2.5 Pre-Treatment/Paint Adhesion (Qualification Testing). When tested with approved phosphate systems, uncoated, or zinc-based coated steels shall be capable of achieving a high quality zinc phosphate conversion coating according to GMW3011. When tested with approved thin film pre-treatments, the requirements of GMW16170 must be fulfilled. Steels with thin organic pre-coatings per GMW15056 are excluded from these requirements, as a pre-treatment will not be deposited. The additional requirements in 3.2.3.2.5.1 through 3.2.3.2.5.4 must be met for thin film organic pre-coating qualification.


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GMW3032

After application of production representative pre-treatment and paint, the steel shall meet the following requirements: 3.2.3.2.5.1 Adhesion of the E-coat shall fulfill test requirements of the crosshatch test according to GMW14829: For samples that are phosphated: Rating 0 as-received and after 120 h humidity exposure per GMW14729.



For samples with thin film pre-treatment, requirements according to GMW16170 shall be met.



3.2.3.2.5.2 Pre-treated (zinc Phosphate and thin film) and E-coated samples must meet delamination test requirements according to GMW14704 (Rating 0 or 1 after 48 h test duration). 3.2.3.2.5.3 For fully painted applications on exposed (E) surfaces, the material shall also meet the requirements of the stone chip resistance test according to GMW14700, Method A, B, and C, with a minimum stone impact rating of 8. ` ` ` ` , , , ` ` , , , , ` ` ` ` , ` ` , ` ` ` , ` ` ` , , , ` -

3.2.3.2.5.4 Creep back resistance shall be inspected on E-coated samples. The samples shall be scribed per GMW15282 and tested according to GMW14872, EXT, (exterior) All, 4 salt spray per cycle, Method 1/2/3, Exposure C. The creep back shall be evaluated per GMW15282 and meet the requirements stated in the following 3 (three) specifications: 

GMW3011 for samples that are phosphated.



GMW16170 for samples with thin film pre-treatment.



GMW15056 for samples with thin organic pre-coating (applicable to thin film organic coating qualification only).

3.2.3.2.6 Adhesive Compatibility (Qualification Testing). Uncoated or zinc based coated steels supplied to this specification shall be capable of being bonded with GM approved adhesives when tested according to GMW16549. Testing to this specification will evaluate bonding characteristics to the metal surface. 3.2.3.2.7 Coating Requirements. Refer to coating requirements in GMW8 for hot dipped coatings, GMW11 for electrogalvanized coatings, GMW16066 for aluminized coatings, and GMW15056 for thin organic precoatings. Coating requirements include, but are not limited to, coating composition, coating mass, and coating adhesion. 3.2.3.3 Microstructure. 3.2.3.3.1 Grain Size. By analysis, grain size when tested to ASTM E112, shall be consistent throughout the thickness of the sheet. Grain size shall be Number 6 or finer for hot rolled substrates, and Number 8 or finer for cold rolled substrates. 3.2.3.3.2 Inclusions. 3.2.3.3.2.1 Inclusion Analysis Methods. Two (2) optional methods for analysis are available. There should be an agreement with the local business unit which of the two (2) following methods have to be performed. 



Method A: ASTM E45 Method D, Plate I-r, by analysis at a magnification of 100x, inclusion content shall not exceed a rating of 2.0 for thin and 2.0 for heavy. Method B: EN 10247, by analysis inclusions shall not exceed size Index 3. In case of diameters <20 mm, they shall not exceed size Index 2.

3.2.3.3.2.2 Inclusion Control. When required by manufacturing or product engineering to improve edge stretching or bending in some applications, a designation may be added to the callout to specify inclusion control ( F” designation, see Section 8, Coding System). The supplier may limit sulfide inclusions content via ultra-low sulfur steelmaking practices and/or may utilize a calcium treatment or rare-earth element (i.e., Cerium) (Ce) addition to control inclusion shape (small globular particles are preferred). Inclusion control shall only apply to LA grades. “

3.2.3.4 Marking. If required, marking shall be carried out on the unexposed surface of full finish coils for outer panels and on the outer side of the coils for inner panels. The marking must be agreed upon between the supplier and purchaser. The ink used for marking must be released by the purchaser. 3.2.3.5 Other Requirements. Requirements such as tolerances on product shape and dimensions, inspections units, number of tests, sampling, test conditions, re-tests, inspection documents, packing, and handling of disputes shall be agreed upon between supplier and the local business unit.


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GMW3032

3.3 Processing Requirements. 3.3.1 Additional Requirements. 3.3.1.1 Weldability. Sheet steel supplied to this standard shall be weldable with standard GM Weld Practices and meet spot weld, arc weld, and laser weld acceptance criteria per GMW14057, GMW14058, and GMW15425 respectively. When required for qualification, testing for spot weldability shall be performed per GWS-5A and approved by the Manufacturing Engineering (ME) - Weld Department of GM Manufacturing Engineering. Contact the GM Weld Council for specific information regarding weldability at [email protected]. 3.3.1.2 Weld Seams in Coils. If weld seams in cold rolled material are allowed by Global Manufacturing Engineering Department, the following restrictions shall be considered: 









For cold reduced coils, pickling weld seams from the manufacturing process of hot rolled coils is permissible without restriction. Punch holes may be used for cold reduced coils to detect weld seams, but must be avoided in stamped parts. For cold reduced coils with exposed (E) or semi-exposed (Z) surfaces, weld seams are permissible, but must be indicated by perforation. For cold reduced coils with unexposed (U) surfaces, weld seams are not permissible unless special exceptions are made by the local organization. For hot rolled coils, weld seams are not permissible.

3.3.1.3 Stretcher Strains. All steel used for exposed (E) surfaces and secondary exposed surfaces located in Zones A, B, and C, as defined by GM Product Quality Standards, shall be free from stretcher strains for six (6) months. The zones will be identified on the manufacturing requirements document GMNA MPS Sheet or other regional manufacturing requirement documents) of the GM Purchase Order or in the purchased stamping Statement of Requirements (SOR). 3.3.1.4 Secondary Work Embrittlement (SWE). Secondary work embrittlement occurs in some interstitial free flat steel products. Secondary work embrittlement testing will be required for any steels that have <0.015% carbon by mass. All material supplied to this specification shall be determined to be free of secondary work embrittlement according to GMW16086 or as agreed upon between the purchaser and supplier. Conformance to this requirement shall be verified at the time of approval and at the time of the initial production shipment, unless otherwise required by the purchaser. 3.4 Performance Requirements. Not applicable. 3.5 Requirements on Other Stages during Life Cycle. 3.5.1 Chemical Requirements. Provisions shall be made to prevent the addition of such elements (see 5.5) from scrap or other materials used in the manufacturing process which would impair the recyclability of the finished components. 3.5.2 Mechanical Requirements. Mechanical property requirements in this specification shall be guaranteed for a minimum of three (3) months after delivery to the manufacturing plant. For materials qualification, required mechanical properties shall be guaranteed for a minimum of six (6) months after coil finishing. 3.5.3 Physical Requirements. Not applicable. 3.5.4 Additional Requirements. 3.5.4.1 Rounding Convention. When determining conformance to this specification, an observed value or a calculated value shall be rounded “to the nearest unit” for the last right -hand digit used in expressing the specification requirement. The rounding method shall be in accordance to the following: 



When the digit beyond the last digit to be retained is <5, the last digit to be retained shall remain unchanged. When the digit beyond the last digit to be retained is ≥5, the last digit to be retained shall be increased by one (1) unit. When employing a rounding method, successive rounding for calculated values should be avoided.


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GMW3032

4 Manufacturing Process Not applicable.

5 Rules and Regulations 5.1 Legal Regulations. All materials must satisfy applicable laws, rules, regulations and recommendations valid in the country of usage. 5.2 Language. In the event of conflict between the English and domestic language, the English language shall take precedence. 5.3 Inspection and Rejection. Samples of components or materials released to a GM material specification shall be tested for conformity with the requirements of this material specification and approved by the responsible Engineering department prior to commencement of delivery of bulk supplies. A new approval must be received for any changes, e.g., properties, manufacturing process, location of manufacture, etc. If not otherwise agreed, all testing and documentation normally required for initial release must be completed. It is the responsibility of the supplier to inform the customer in a timely manner, without solicitation, and to include documentation of all modifications of materials and/or processes and to apply for a new release. If not otherwise agreed, all release tests shall be repeated and documented by the supplier prior to commencement of delivery of non-conforming bulk supplies. In individual cases, a shorter test can be agreed to between the responsible Engineering department and the supplier. 5.4 Material Safety Data Sheets/Safety Data Sheets (MSDS/SDS). For new product submissions, or when a change in chemical composition of an existing product has occurred, a complete copy of the Material Safety Data Sheet/Safety Data Sheet must be submitted in compliance with the Globally Harmonized System of Classification and Labeling of Chemicals (GHS) requirements or other country-specific MSDS/SDS requirements. In addition, product MSDS/SDS submissions must be in compliance with specific country General Motors TMC003 Material Safety Data Sheet/Safety Data Sheet guidance documents where available. 5.5 All materials supplied to this standard must comply with the requirements of GMW3059 , Restricted and Reportable Substances for Parts.

6 Approved Sources Materials supplied to this specification must be approved by General Motors. A list of approved materials can be found in the sheet metal approved source list in GM SupplyPower. (Document Library Engineering GM North America Product Design). This GM Material File is provided to third parties to reduce redundant testing of materials. If approved material already listed is used, the part supplier can use GM Material File reference for Production Part Approval Process (PPAP) material approval. If the decision is made to use a not yet approved material, contact the GM Materials Engineering for details on the approval process. The material approval process must be completed prior to PPAP start date of the part supplied to General Motors.

7 Notes 7.1 Glossary. Not applicable. 7.2 Acronyms, Abbreviations, and Symbols. AI

Anisotropy Index

AS

Australian Standard

ASTM

ASTM International

BH

Bake Hardenable

BHI

Bake Hardening Index

Ce

Cerium


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` , , , ` ` ` , ` ` ` , ` ` , ` ` ` ` , , , , ` ` , , , ` ` ` ` -

GM WORLDWIDE ENGINEERING STANDARDS CR

Cold Rolled

DIN

German Institute for Standardization

DOI

Distinction of Image

DP

Dual Phase

E

Exposed

ELPO

Electrodeposited Primer, Cathodic E-coat

EN

European Standard

EXT

Exterior

GHS

Globally Harmonized System of Classification and Labeling of Chemicals

GMB

GM Brazil

GME

GM Europe

GMK

GM Korea

GMNA

GM North America

GMW

GM Worldwide

GPSC

Global Purchasing and Supply Chain

HAZ

Heat Affected Zone

HR

Hot Rolled

HSLA

High Strength Low Alloy

IF

Interstitial Free

ISO

International Organization for Standardization

JIS

Japanese Industrial Standards

LA

Low Alloy

ME

Manufacturing Engineering

MPa

Megapascal

MPS

Material Parts Specification

MSDS

Material Safety Data Sheet

N/A

Not applicable

P

Re-phosphorized

PPAP

Production Part Approval Process

ppm

Parts Per Million

Ra

Roughness Average

ReL

Lower Yield Stress

r m

r-bar

Rp

Proof Stress

RPc

Roughness Peak Count

SA

Structural Automotive

SDS

Safety Data Sheet

SOR

Statement of Requirements

SWE

Secondary Work Embrittlement

t

Thickness

T

Temper Rolled

T

Tensile Strength

U

Unexposed

VDA

German Association of the Automotive Industry (Verband der Automobilindustrie)

GMW3032


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GM WORLDWIDE ENGINEERING STANDARDS WH

Work Hardening

WHI

Work Hardening Index

YS

Yield Strength

Z

Semi-Exposed

GMW3032

8 Coding System This standard shall be referenced in other documents, drawings, etc., as follows: Material per GMW3032 The coding system for GMW sheet steel specifications on engineering part drawings and GMNA Manufacturing Engineering Metal Parts Specifications (MPS) Sheets and/or electronic math data files shall use a nomenclature consisting of the material designation, minimum yield strength and surface quality or coating designation. The engineering part drawing may also include the steel product type (HR or CR). If manufacturing and/or product engineering determines the steel requires inclusion-control, an “F” may be included following the steel type. Hot rolled HSLA grades that are inclusion controlled and need to have banding free microstructure are designated by “B” in the material designation. In addition, if the engineering part drawing does not include the steel product type (HR or CR), the manufacturing engineering group shall select the desired product type based on such factors as availability, formability and cost, and shall include this information on the appropriate engineering documents. The material designation is defined by the applicable GMW base metal material specification which follows the GMW specification number system. The minimum yield strength is specified in Megapascals (MPa) by a numerical designation. The surface quality is designated as either E for exposed, or U for an unexposed application and T for temper rolled. For coated applications, refer to GMW8 for hot dip zinc coatings, GMW11 for electrogalvanized coatings, and GMW16066 for aluminized coatings. The GMW sheet steel specification shall be called out on engineering drawings and manufacturing engineering documents as follows: 8.1 Example of coding for uncoated high strength steel. 8.1.1 Example of engineering part drawing and/or electronic math data file coding for uncoated high strength steel. GMW3032M-ST-S-CR180P-UNCOATED-E Where: GMW

= Validation Area (GM Worldwide)

3032

= Sequential Number

GMW3032

= Material Type (Base material specification)

M

= Material Type: Metals

ST

= Category: Steel

S

= Subcategory: Sheet

CR

= Steel Product Type: Cold rolled

180

= Minimum Yield Strength (MPa)

P

= Steel Type (B0, B2, IF, LA, P)

UNCOATED

= Uncoated Substrate Designation

E

= Surface Quality (see 3.2.3.2.2)

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GMW3032

8.1.2 Example of manufacturing engineering document coding uncoated high strength steel. GMW3032M-ST-S-CR180P-UNCOATED-E Where: GMW


3032

= Sequential Number

GMW3032

= Material Type (Base material specification)

M


ST

= Category: Steel

S


CR


180


P


UNCOATED


E


8.2 Example of coding for hot dip zinc coated high strength steel. 8.2.1 Example of engineering part drawing and/or electronic math data file coding for hot dip zinc coated high strength steel. GMW3032M-ST-S-CR180P-HD60G60G-U Where: GMW


3032

= Sequential number

GMW3032

= Material Type (Base material specifications)

M


ST

= Category: Steel

S


CR


180


P


HD60G60G

= Coating Designation (GMW8 for details)

U


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GMW3032

8.2.2 Example of manufacturing engineering document coding for hot dip zinc coated high strength steel: GMW3032M-ST-S-CR180P-HD60G60G-U Where: GMW


3032

= Sequential number

GMW3032

= Material Type (Base Material Specifications)

M


ST

= Category: Steel

S


CR


180


P


HD60G60G


U


8.3 Example of Coding for Electrogalvanized Coated High Strength Steel. Per 1.1, for engineering part drawing or electronic math file coding, the HSLA steels (except for SA grades) <550 MPa, the HR or CR designations shall not be used. For manufacturing or Global Purchasing and Supply Chain (GPSC) purchasing document coding, the HR or CR designation may be used, as necessary. 8.3.1 Example of engineering part drawing or electronic math file coding for electrogalvanized coated high strength steel. GMW3032M-ST-S-420LA-EG60G60G-U Where: ` ` ` ` , , , ` ` , , , , ` ` ` ` , ` ` , ` ` ` , ` ` ` , , , ` -

GMW


3032

= Sequential Number

GMW3032


M


ST

= Category: Steel

S


420


LA


EG60G60G


U



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GMW3032

8.3.2 Example of manufacturing engineering document coding for electrogalvanized coated high strength steel. GMW3032M-ST-S-CR420LA-EG60G60G-U Where: GMW


3032

= Sequential Number

GMW3032


M


ST

= Category: Steel

S


CR


420


LA


EG60G60G


U


8.4 Example of coding for hot dip coated high strength steel requiring temper roll. 8.4.1 Example of engineering part drawing or electronic math file coding for temper rolled electrogalvanized coated high strength steel. GMW3032M-ST-S-340LA-EG60G60G-T Where: GMW


3032

= Sequential Number

GMW3032


M


ST

= Category: Steel

S


340


LA


EG60G60G


T

= Temper Roll Designation


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GMW3032

8.4.2 Example of manufacturing engineering document coding for temper rolled electrogalvanized coated high strength steel. GMW3032M-ST-S-CR340LA-EG60G60G-T Where: GMW


3032

= Sequential Number

GMW3032


M


ST

= Category: Steel

S


CR


340


LA


EG60G60G


T

= Temper Roll Designation

8.5 Example of coding for hot dip coated high strength steel requiring inclusion control. 8.5.1 Example of engineering part drawing or electronic math file coding for inclusion-controlled hot dip coated high strength steel. GMW3032M-ST-S-340LAF-HD60G60G-U Where: GMW


3032

= Sequential Number

GMW3032


M


ST

= Category: Steel

S


340


LA


F

= Inclusion-Controlled

HD60G60G


U



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GMW3032

8.5.2 Example of manufacturing engineering or GPSC purchasing document coding for inclusion-controlled hot dip coated high strength steel. GMW3032M-ST-S-HR340LAF-HD60G60G-U Where: GMW


3032

= Sequential Number

GMW3032


M


ST

= Category: Steel

S


HR

= Steel Product Type: Hot rolled

340


LA


F


HD60G60G


U


8.5.3 Example of engineering part drawing or electronic math file coding for Structural Automotive hot rolled uncoated steel ` ` ` ` , , , ` ` , , , , ` ` ` ` , ` ` , ` ` ` , ` ` ` , , , ` -

GMW3032M-ST-S-HR440T-SA-UNCOATED-U

Where: GMW


3032

= Sequential Number

GMW3032


M


ST

= Category: Steel

S


HR


440

= Minimum Tensile Strength (MPa)

T

= Tensile Strength

SA

= Structural Automotive

UNCOATED


U



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GMW3032

8.5.4 Example of engineering part drawing or GPSC purchasing document for banding controlled hot dip coated high strength steel. GMW3032M-ST-S-HR550LAF-B-HD60G60G-U Where: GMW


3032

= Sequential Number

GMW3032


M


ST

= Category: Steel

S


HR


550


LA


F


B

= Banding Controlled

HD60G60G


U


` , , , ` ` ` , ` ` ` , ` ` , ` ` ` ` , , , , ` ` , , , ` ` ` ` -


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GMW3032

9 Release and Revisions This standard was originated in July 1998. It was first approved by GM Automotive Operations-North America Sheet Metal Specialists Team, and a team of GM Europe, Latin America, and Asia Pacific materials engineering experts excluding ISUZU in February 1999. It was first published in June 1999. Issue

Publication Date

Description (Organization)

1

JUN 1999

2

OCT 2000

3

AUG 2002

4

OCT 2005

5

AUG 2007

Revised title, paragraphs 1.1, 1.1.1 (all tables), 2 (2.1-2.3 references), 3.1.1.2, 3.1.2, 3.1.2.1, 3.1.3.2.2, 3.1.3.2.3, 3.1.3.2.4, 3.1.3.2.5 3.1.3.3.2, 3.2.1.3, 3.4.4.1, 5.1.1, 7.2, 8 (8.1-8.4), Table 1, Table 2, Table 3, Table 5, Appendix A (added), Appendix B (renamed), Appendix C (added), Deviations – 3.1.1.1, Table Dev 1, 3.1.3.2.4, Table Dev 2 (Global Sheet Metal Specialist Team)

6

OCT 2009

7

JAN 2013

8

JUN 2014

Updated specification template, 2.2 Updated References, 3.2.1.1 End-product referee method, 3.2.1.2 Surface Treatment per GMW14019, 3.2.3.2.3 Phosphateability/Paint Compatibility, updated to GMW14704, added semi-exposed surface, 3.2.3.3.2.1 Updated ASTM Plate, 3.3.1.4 Updated to GMW16086, 5.3 Initial Source Approval added, Table 4 (240LA requirements revised), Table 5 (elongation for HR550 modified, Note 8 added), Appendix B (Note 1 added), Appendix C updated, Deviations – 3.2.2 GM Holden added, GM Europe updated, Deviations - 3.2.3.2.1 GM Holden (removed regional specs, 3.2.3.2.5 Coating Adhesion by Bonding) (GME only) (Global Sheet Metal Specialist Team) Paragraph 1.1: Banding-free microstructure requirements added, SA grades added, and temper rolling requirements designation added. Paragraphs 2 and 3.2.2.1 updated. Paragraph 3.2.2.2: Bend Requirements for Structural Automotive Grades added. Paragraphs 3.2.3.2., 3.2.3.2.3, 3.2.3.2.4, 3.2.3.2.5, 3.2.3.2.6, 3.2.3.2.7 and 7 updated. Paragraph 3.3.1.1 Spot Weld requirements updated and Laser W eld requirements added. Paragraph 3.5.2 Mechanical requirements updated. Paragraphs 7 and 8 updated, to reflect engineering and manufacturing requirements for high strength steels, and added examples of structural automotive and banding free grades. Table 2 updated to show HR designations for 550LA and higher strength grades, and inclusion of SA (all grades). Table 3 updated by removing B0 bake hard grades. Table 6 added for Hot Rolled Structural Automotive Grades for Chassis Applications. Appendix A updated by deleting crossreference Tables A1 and A2, and added a new cross-reference Table A1 for Structural Automotive grades. Appendix C: Tables C1, C2, C3 and C4 deleted. New Appendix C added for Anisotropy Index for banding free grades. Deviation Section: Paragraphs 3.2.1, 3.2.2, 3.2.3, and Table Dev 1 updated. Appendix A, Table A1, Specification corrected to JIS G 3113-SAPH440. Removed GM6180M from 2.2. Clarified language in Section 6 Approved Sources, and Section 8 Coding System. Updated 3.2.1.2 Surface Treatment with revised specifications GMW16546 and GMW16656. Removed obsolete reference specification GMW14019. (Ferrous Sheet Metal Global Subsystem Leadership Team)

Initial publication. With this released Revision A, the document is also valid for Isuzu. Rework of paragraphs 1, 2.1, 2.3, 3.1.1.1, 3.1.2, 3.1.2.1, 3.1.2.2, 3.1.3.1, 3.1.3.2.1, 3.1.3.2.2, 3.1.3.3.1, 3.1.3.4, 3.1.3.5, 3.2.4.3, 5, 7: Addition of Dualphase Grades (DP). Deletion of grades: 2 40P, 270P, 300P, CR460, HR460. For all chemical composition tables: the required aluminum was changed from maximum to minimum required value, the manganese content is now equal for HR and CR grades. All tables were reworked. Attention: The grade referenced on drawings or other documentation as GMW3032M-ST-S HR210 is replaced by GMW2M-ST-S HR1. (GME Specification Center) Revision B was approved on 17/DEC/2001 // Revised paragraphs 2.1, 2.2, 2.3, 3.1.2, 3.1.1.2, 3.1.2.1, 3.1.3.1, 3.1.3.2.1.1, 3.1.3.5, 3.2.1.4, 7.1, 7.2, 7.3, Table 4, Table 5, Table 6, Table 7, Appendix A - Deviation section. (GME Specification Center) Revised paragraphs 1, 1.1, 1.1.1.1, 1.1.1.2, 1.3, 2.1, 2.2, 2.3, 3.1.1.1, 3.1.1.2, 3.1.2, 3.1.2.1, 3.1.3.2.1, 3.1.3.2.2, 3.1.3.2.3, 3.1.3.2.4, 3.2.1.2, 3.2.1.3, 5.4, 5.5, 6, 7, 7.1.1, 7.1.2, 7.2.1, 7.2.2, 7.3.1, 7.3.2, Table 1, Table 2, Table 3, Table 4, Table 5, A, A3.1.1.1, A3.1.1.2, A3.1.2, Table A1, A3.1.3, A3.1.3.1, A3.1.3.2, A3.1.3.2.1, A3.1.3.2.2, A3.2, Table A2, A6. Revised current specification based on mill capability and global requirements.


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GMW3032

Table 1: Bake Hardenable and Solid Solution Strengthened Grades Chemical Compositions Note 1, Note 2, Note 3 GMW3032M-ST-S

C

Mn

P

S

Al

Si

% Maximum

% Maximum

% Maximum

% Maximum

% Minimum

% Maximum

CR180

0.06

0.70

0.08

0.030

0.015

0.50

CR180IF

0.01

0.70

0.08

0.025

0.010

0.30

CR210

0.08

0.70

0.08

0.030

0.015

0.50

CR210IF

0.01

0.90

0.08

0.025

0.010

0.30

CR240

0.10

1.00

0.10

0.030

0.015

0.50

CR240IF

0.01

1.60

0.10

0.025

0.010

0.30

CR270

0.12

1.50

0.11

0.030

0.015

0.50

CR300

0.12

1.50

0.12

0.030

0.015

0.50

Designation

Note 4, Note 5

Note 1: Chemical composition based on product (coil or sheet/blank) analysis. Note 2: In addition to requirements shown in Table 1, % Cu +% Ni + % Cr + % Mo ≤0.5. Note 3: % C + % P ≤0.16. Note 4: Includes IF, P, B0 and B2 grades. Note 5: All P and IF grades with <0.015% carbon shall have a minimum of 0.0003% (3 ppm) Boron. See Deviations Section.

Table 2: Cold or Hot Rolled High Strength Low Alloy Grades Chemical Composition Note 1, Note 2, Note 3 GMW3032M-ST-S

C

Mn

P

S

Al

Si

Designation

% Maximum

% Maximum

% Maximum

% Maximum

% Minimum

% Maximum

240LA

0.10

0.70

0.030

0.030

0.015

0.50

270LA

0.12

1.00

0.030

0.030

0.015

0.50

300LA

0.12

1.30

0.030

0.030

0.015

0.50

340LA

0.12

1.50

0.030

0.030

0.015

0.50

380LA

0.12

1.50

0.030

0.030

0.015

0.60

420LA

0.12

1.60

0.030

0.030

0.015

0.60

500LA

0.12

1.70

0.030

0.030

0.015

0.60

HR550LA Note 4

0.15

1.80

0.030

0.030

0.015

0.60

HR650LA Note 4

0.12

2.00

0.025

0.015

0.015

0.60

HR700LA Note 4

0.12

2.10

0.025

0.015

0.015

0.60

SA (all grades) Note 5

-

-

0.040

0.040

-

-

Note 1: Chemical composition based on product (coil or sheet/blank) analysis. Note 2: LA grades must contain intentional additions of micro alloying elements (i.e., niobium, titanium, and/or vanadium) and/or shall have a carbon equivalence, CE, of 0.24 maximum, where CE = % C + (%Si/30) + (%Mn/20) + 2(%P) + 4(%S). Note 3: The amount of micro alloying elements (niobium, titanium, vanadium) for the Low Alloy (LA) steels together shall be ≤0.22%. Note 4: Grades 550 and above only available as HR substrates. Note 5: Structural Automotive (SA) grades carbon equivalence, CE, of 0.24 maximum where CE = % C + (% Si/30) + (% Mn/20) + 2(% P) +4(% S). ` ` ` ` , , , ` ` , , , , ` ` ` ` , ` ` , ` ` ` , ` ` ` , , , ` -


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GMW3032

Table 3: Cold Rolled Bake Hardenable and Solid Solution Strengthened Grades Mechanical Property RequirementsNote 1 Yield Strength Note 2 (MPa)

GMW3032M-ST-S

Designatio n

Minimum

Tensile Strength (MPa)

Maximum

r m (r-bar)

Note 3, Note 4

Total Elongation JIS Number 5 50 mm (%) Note 3

Minimum

Minimum

Minimum

Total Elongation 50 mm (%)


Minimum

Minimum

Note 4 Note 5

n value

r 0-20 Note 8

Note 4 Note 8

BH2 Note 7

n value Note 4

(MPa)

Note 6

Minimum

Minimum

Minimum

Minimum

CR180P

180

240

300

35

33

39

1.3

---

---

0.20

----

CR180IF

180

240

330

38

36

42

1.3

1.2

0.19

0.20

----

CR180B2

180

240

300

35

33

39

1.3

1.1

0.17

0.19

30

CR210P

210

270

320

33

31

37

1.3

---

0.16

0.19

----

CR210IF

210

270

340

36

34

40

1.3

1.1

0.18

0.19

----

CR210B2

210

270

320

33

31

37

1.1

1.1

0.16

0.17

30

CR240P

240

300

340

30

28

34

1.1

---

0.15

---

---

CR240IF

240

300

360

34

32

38

1.1

1.0

0.17

0.17

---

CR240B2

240

300

340

30

28

34

1.1

1.0

0.15

0.17

30

CR270P

270

330

360

28

26

32

1.0

---

0.14

---

---

CR270B2

270

330

360

28

26

32

0.9

---

0.13

0.15

30

CR300B2

300

360

390

26

24

30

0.9

---

---

0.14

30

Note 1: Additional demands can be specified by local units. Note 2: The yield stress values shall apply for the 0.2 proof stress, Rp 0.2, if the yield stress cannot be easily recognized, otherwise the values shall be the lower yield stress, ReL. Note 3: When the specified nominal thickness <0.7 mm and >0.5 mm, the minimum value for elongation is reduced by 2 units. For thickness≤0.5 mm, the minimum value is reduced by 4 units. Note 4: ZnNi and Galvanneal coated steels: r m (r-bar) shall be reduced by 0.1; n value to be reduced by 0.01; total elongation to be reduced by 2%. Note 5: For thickness >1.6 mm, the m inimum r-value requirement will be 1.0. Note 6: Calculation by (r 0+r 90+2r 45)/4. Note 7: The BH2 index requirement in this specification is used to characterize the general bake hardening response of steel. For vehicle design, the actual processing conditions (temperature cycle, pre-straining, etc.,) shall be considered. Note 8: Valid only for GME.


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GMW3032

Table 4: Cold Rolled High Strength Low Alloy Grades Mechanical Property Requirements Note 1

GMW-3032M-ST-S

Note Note Note Note

Yield Strength (MPa)

Note 2




Total Elongation JIS Number 5 50 mm (%)

n-value Note 4

Designation

Minimum

Maximum

Minimum

Minimum

Minimum

Minimum

CR240LA

240

320

320

28

26

32

Minimum 0.15

CR270LA

270

350

330

26

24

30

0.15

CR300LA

300

380

370

24

22

28

0.14

CR340LA

340

420

410

22

20

26

0.13

CR380LA

380

460

450

20

18

24

0.12

CR420LA

420

520

480

18

16

22

0.11 Note 3

CR500LA

500

600

560

16

14

20

0.09 Note 3

1: Additional demands can be specified by local units. 2: The yield stress values shall apply for the 0.2 proof stress, (Rp) 0.2, if the yield stress cannot be easily recognized, otherwise the values shall be the lower yield stress, ReL. 3: n-value tested from 6% to end of uniform elongation. 4: ZnNi and Galvanneal coated steels: n value to be reduced by 0.01.


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GMW3032

Table 4: Cold Rolled High Strength Low Alloy Grades Mechanical Property Requirements Note 1

GMW-3032M-ST-S

Note Note Note Note

Yield Strength (MPa)

Note 2




Total Elongation JIS Number 5 50 mm (%)

n-value Note 4

Designation

Minimum

Maximum

Minimum

Minimum

Minimum

Minimum

CR240LA

240

320

320

28

26

32

Minimum 0.15

CR270LA

270

350

330

26

24

30

0.15

CR300LA

300

380

370

24

22

28

0.14

CR340LA

340

420

410

22

20

26

0.13

CR380LA

380

460

450

20

18

24

0.12

CR420LA

420

520

480

18

16

22

0.11 Note 3

CR500LA

500

600

560

16

14

20

0.09 Note 3

1: Additional demands can be specified by local units. 2: The yield stress values shall apply for the 0.2 proof stress, (Rp) 0.2, if the yield stress cannot be easily recognized, otherwise the values shall be the lower yield stress, ReL. 3: n-value tested from 6% to end of uniform elongation. 4: ZnNi and Galvanneal coated steels: n value to be reduced by 0.01.

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GMW3032

Table 5: Hot Rolled High Strength Low Alloy Grades Mechanical Property Requirements Note 1

GMW3032M-ST-S

Yield Strength Note 2, Note 3 (MPa)

Total Elongation 80 mm (%) Note 2

Total Elongation (JIS Number 5) 5 mm (%)

n-value Note 4

(MPa)


Tensile Strength Note 2

Designation

Minimum

Maximum

Minimum

Minimum

Minimum

Minimum

Minimum

HR240LA

240

320

290

31

29

35

0.16

HR270LA

270

350

330

29

27

33

0.15

HR300LA

300

380

370

27

25

31

0.14

HR340LA

340

420

410

25

23

29

0.13

HR380LA

380

460

450

23

21

27

0.12

HR420LA

420

520

480

22

20

26

0.11 Note 5

HR500LA

500

600

560

20

18

24

0.09 Note 5

HR550LA

Note 6

550

650

610

18

16

22

0.08 Note 5

HR650LA

Note 6

650

780

700

14

12

20

0.07 Note 5

HR700LA

Note 6

700

850

750

12

10

18

0.06 Note 5

Note 1: Additional demands can be specified by local units. Note 2: The values stated apply to product thicknesses from 2 mm to 8 mm in the as-delivered condition. Higher or lower values of thickness and other as delivered conditions may be agreed at the time of ordering. Note 3: The yield stress values shall apply for the 0.2 proof stress, Rp 0.2, if the yield stress cannot be easily r ecognized, otherwise the values shall be the lower yield stress, ReL. Note 4: Galvanneal coated steels shall be reduced by 0.01. Note 5: n-value tested from 6% to end of uniform elongation. Note 6: For hot-dipped zinc coated HR grades with Yield Strength (YS) ≥550 MPa, the minimum total elongation shall be reduced by 3%. See Deviations Section.


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GMW3032

Table 5: Hot Rolled High Strength Low Alloy Grades Mechanical Property Requirements Note 1

GMW3032M-ST-S

Total Elongation 80 mm (%) Note 2

Total Elongation (JIS Number 5) 5 mm (%)

n-value Note 4

(MPa)


Tensile Strength

Yield Strength Note 2, Note 3 (MPa)

Note 2

Designation

Minimum

Maximum

Minimum

Minimum

Minimum

Minimum

Minimum

HR240LA

240

320

290

31

29

35

0.16

HR270LA

270

350

330

29

27

33

0.15

HR300LA

300

380

370

27

25

31

0.14

HR340LA

340

420

410

25

23

29

0.13

HR380LA

380

460

450

23

21

27

0.12

HR420LA

420

520

480

22

20

26

0.11 Note 5

HR500LA

500

600

560

20

18

24

0.09 Note 5

HR550LA

Note 6

550

650

610

18

16

22

0.08 Note 5

HR650LA

Note 6

650

780

700

14

12

20

0.07 Note 5

HR700LA

Note 6

700

850

750

12

10

18

0.06 Note 5

Note 1: Additional demands can be specified by local units. Note 2: The values stated apply to product thicknesses from 2 mm to 8 mm in the as-delivered condition. Higher or lower values of thickness and other as delivered conditions may be agreed at the time of ordering. Note 3: The yield stress values shall apply for the 0.2 proof stress, Rp 0.2, if the yield stress cannot be easily r ecognized, otherwise the values shall be the lower yield stress, ReL. Note 4: Galvanneal coated steels shall be reduced by 0.01. Note 5: n-value tested from 6% to end of uniform elongation. Note 6: For hot-dipped zinc coated HR grades with Yield Strength (YS) ≥550 MPa, the minimum total elongation shall be reduced by 3%. See Deviations Section.


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GMW3032

Table 6: Hot Rolled Structural Automotive Grades (Intended for Chassis Applications) M echanical Property RequirementsNote 1, Note 2 Total Elongation (JIS Number 5) Yield Strength Note 3 GMW3032M-ST-S

50 mm

Bendability

(%)


Thickness, t (mm)

Thickness, t (mm)

t <6.0

6.0 ≤t <8.0

8.0 ≤t ≤14.0

1.6 ≤t <2.0

2.0 ≤t <2.5

2.5 ≤t <3.15

3.15 ≤t <4.0

4.0 ≤t <6.3

6.3 ≤t ≤14.0

Designation

Minimum

Minimum

Minimum

Minimum

Minimum

Minimum

Minimum

Minimum

Minimum

Minimum

HR370T-SA

370

225

225

215

32

33

35

36

37

25

HR440T-SA

440

305

295

295

29

30

32

33

34

22

Bend Angle

Inside Radius Thickness, t (mm)

180 180

t <2.0

T ≥2.0

T × 0.5

t × 1.0

T × 1.0

t × 1.5

Note 1: Additional demands can be specified by local units. Note 2: Test per ISO 7438 transverse to rolling direction. Note 3: The yield stress values shall apply for the 0.2 proof stress, Rp 0.2, if the yield stress cannot be easily recognized, otherwise the values shall be the lower yield stress, ReL.

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GMW3032

Table 6: Hot Rolled Structural Automotive Grades (Intended for Chassis Applications) M echanical Property RequirementsNote 1, Note 2 Total Elongation (JIS Number 5) Yield Strength Note 3 GMW3032M-ST-S

50 mm

Bendability

(%)


Thickness, t (mm)

Thickness, t (mm)

t <6.0

6.0 ≤t <8.0

8.0 ≤t ≤14.0

1.6 ≤t <2.0

2.0 ≤t <2.5

2.5 ≤t <3.15

3.15 ≤t <4.0

4.0 ≤t <6.3

6.3 ≤t ≤14.0

Designation

Minimum

Minimum

Minimum

Minimum

Minimum

Minimum

Minimum

Minimum

Minimum

Minimum

HR370T-SA

370

225

225

215

32

33

35

36

37

25

HR440T-SA

440

305

295

295

29

30

32

33

34

22

Bend Angle

Inside Radius Thickness, t (mm)

180 180

t <2.0

T ≥2.0

T × 0.5

t × 1.0

T × 1.0

t × 1.5

Note 1: Additional demands can be specified by local units. Note 2: Test per ISO 7438 transverse to rolling direction. Note 3: The yield stress values shall apply for the 0.2 proof stress, Rp 0.2, if the yield stress cannot be easily recognized, otherwise the values shall be the lower yield stress, ReL.

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GMW3032

Appendix A Table A1: Structural Automotive Grades GM Worldwide

GM North America

GM Europe

GM Brazil

GM Korea

GMW3032M-ST-SHR370T-SA

JIS G 3113-SAPH370


JIS G 3113-SAPH440


GMW3032

Appendix A Table A1: Structural Automotive Grades GM Worldwide

GM North America

GM Europe

GM Brazil

GM Korea


JIS G 3113-SAPH370


JIS G 3113-SAPH440


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GMW3032

Appendix B Figure B1 and Figure B2 illustrate the definition of the Bake Hardening Index (BHI) and Work Hardening Index (WHI) on schematic diagrams of stress-strain curves. Graphical descriptions of the BH 0 bake hardening index determined at 0% pre-strain (not pre-strained), and the BH 2 bake hardening and work hardening indices determined at 2% pre-strain are shown on Figure B1 and Figure B2, respectively. The bake hardening index for bake hardenable steels shall be determined on specimens that are not pre-strained and 2% pre-strained and baked at +170 °C for 20 minutes. Standard test specimens will be taken from unstrained and unbaked material in the longitudinal (rolling) direction and tested per ISO 6892 or ASTM A370. Figure B1: Determination of Bake Hardening (No Pre-Strain)

170°C/20 minutes

Figure B2: Determination of Bake Hardening and Work Hardening Indexes (Pre-Strain)

Note 1

170°C/20 minutes

Note 1

BH2

Stress

BHo Stress WH

WH = Work Hardening

Strain

2% Pre-Strain

Strain

Note 1: The industry standard time and temperature to evaluate general bake hardenability of steel is +170 °C for 20 minutes. This standard is independent of the minimum time and temperatures required to effectively activate bake hardening. The GM standard minimum ELPO paint bake oven requirements of +160 °C for 15 minutes for heavy metal sections is adequate to meet the intent of the bake hardening requirements of these steels.


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GMW3032

Appendix C When specified as a suffix letter B, the steel shall meet an Anisotropy Index, AI = 2.0 level of microstructural orientation according to ASTM E1268. Example: GMW3032M-ST-S-HR550LAF-B-Uncoated-U

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GMW3032

Deviations Note: Paragraph numbers may not appear sequentially, due to only those with deviations are included in this section. Deviations on requirements for individual GM business units. In case of disputes or conflicts, the corresponding local standards and norms, GM North America, GM Europe, GM Brazil, and GM Korea shall apply. Dev 3.2.1.1 Base Metal. GM Korea: Steel products shall have chemical composition which is agreed between purchaser and supplier which is capable of achieving the desired mechanical properties specified in GMW3032M-ST-S. GM North America: Maximum phosphorus content in Table 2 of 0.06% is permissible with welding approval. All P grades with <0.015% carbon must contain a minimum of 0.0003% (3 ppm) boron or must have a BH 2 value of 20 MPa minimum. GM Europe: The chemical composition of the base material in percent (%) by mass determined per ISO 14284 shall meet the requirements listed in Table 1 and Table 2. The contents of unlisted elements are to the choice of the producer as long as they do not affect the specified requirements and the production processes. Dev 3.2.1.2 Surface Treatment. GM Korea: For cold rolled and hot rolled steel supplied to this specification, mill oils, shipping oils, press oils, etc., applied to the material by the steel mill and the parts manufacturer must be removable in the purchaser’s phosphate pre-cleaning system. The material must be capable of achieving an even phosphate coating in the purchaser’s phosphate system. The phosphate coating weight and crystal morphology must be as expected for that type of sheet metal material phosphate coating in the purchaser’s phosphate system. Dev 3.2.2 Mechanical Requirements. GM Brazil: Designation of carry over parts to be used on global platform vehicles must be changed into the new GMW Material Description System. GM North America: Bake Hardening Index (shown in Table 3), BH 2, shall be 20 MPa minimum. GM Holden: Maximum yield strength for C R240LA (Table 4) shall be increased by 30 MPa for product thickness <1.8 mm. GM Europe: Total elongation for coated and uncoated HR550LA shall be 13% minimum. Designation of carry over parts to be used on global platform vehicles must be changed into the new GMW Material Description System. GM Brazil: The r m (r-bar) values for bake hardenable and solid solution strengthened grades shall meet the requirements in Table Dev 1. ` ` ` ` , , , ` ` , , , , ` ` ` ` , ` ` , ` ` ` , ` ` ` , , , ` -

Table Dev 1: Bake Hardenable and Solid Solution Strengthened Grades Mechanical Property Requirements Note 1 GMW3032M-ST-S Designation

r m (r-bar )

CR180P

1.3

CR180B2

1.3

CR210P

1.3

CR210B2

1.3

CR240B2

1.2

CR270B2

1.0

CR300B2

1.0

Note 1: GM Korea : Australian and Japanese Steel Suppliers for Holden shall perform tensile testing to Australian Standard AS 1391, and to Japanese Industrial Standard JIS Z 2201 (No. 5 test piece), respectively.


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GMW3032

Dev 3.2.3 Physical Requirements. Dev 3.2.3.2 Surface Requirements. Dev 3.2.3.2.1 Surface Texture. GM Korea: To satisfy Holden exterior topcoat system requirements (GMW3005), the surface texture of materials used for highly visible exterior surface of the vehicle must not decrease the distinction of image (DOI) or gloss of the applied paint. GM North America: Refer to GMW16823. GM Europe: Refer to EN 10049. Dev 3.2.3.2.2 Surface Quality. GM Korea: All products shall be free from stretcher strains for six (6) months unless otherwise agreed upon between purchaser and supplier. Surface finish and quality should be negotiated between the steel mills and parts manufacturer to be appropriate to the final use of the part. In all cases, the supplied steel and the parts made from that steel shall be clean and free of scale, stains, corrosion, debris or any other defects which would be objectionable on the finished part. GM Europe: Exposed (E) and unexposed (U) cold rolled and coated products are to be temper rolled. GM North America: Refer to GMW16823. Table Dev 2: Typical Inside Bend Radii Cold and Hot Rolled HSLA Steel GMW3032M-ST-S Designation

Cold Rolled Bend Radius/Thickness

Note 1, Note 2, Note 3, Note 4

Hot Rolled Note 5

Bend Radius/Thickness

270

1/2 T

1T

300

1/2 T

1T

340

1/2 T and L

1T

380

1 T and L

1 T and L

420

1 T and L

1 T and L

500

2 T and L

3 T and L

550

N/A

3 T and L

650

N/A

3 T and L

700

N/A

3 T and L

Note 1: Ratio of bend radius to thickness T = t ransverse specimen and L = longitudinal specimen. Note 2: The suggested minimum bending radius is on nominal rolled thickness, not the minimum ordered thickness. Note 3: For thickness over 4.40 mm, add 1/2 “T” to radius shown in table. Note 4: These data are only applicable to tooling design. Note 5: N/A = Not applicable.


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GMW3032

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