Materials Science Notes by Prof. Manuelito Radam

Engineering Materials By: Lito Lito D. Radam, Radam, PME, PME, MSME MSME Engineering Professor

Objectives 

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Be able to familiarize the meaning of various engineerin engineering g terms that are commonly use in Materials & Testing. Testing. To understand understand the uses of different engineering materials in various industries and in manufacturing of goods.

Understand & able to identify identif y the basic application of various engineering materials and its functionality.

Effects of Various Elements in Steels Alloying Elements & Their Effects On The Properties of Steel

Residual Elements in Steels Common Uses of Alloy Steel Refrat Ref ratory ory Met Metal alss & All Alloy oyss

Effects of Various Elements in Steels 1. Boron 2.

- impr improv oves es hard harden enab abil ilit ityy, without the loss of machinability and formability. . - deoxidiz deoxidizes es steels, steels, improve improvess Calcium toughness, and may may improve formability formabil ity and machinability machinability..

3. Carbon

- impr impro oves har hardena denabi bili lity ty,, strength, hardness, and wears resistance; it reduces ductility, weldability, and toughness.

Effects of Various Elements in Steels 4. Cerium -

- controls the shape of

inclusions and improves toughness in high-strength, low-alloy steels; it deox deoxid idiz izes es stee steels ls..

5. Chromium -

improves toughness, hardenability, wear and corrosion resistance, and high-temperature strength; it increases the depth of hardness penetration resulting from heat treatment, by prom promot otin ing g carb carbur uriz izat atio ion n

Effects of Various Elements in Steels 6. Cobalt 7.

improves strength and hard hardne ness ss at elev elevat ated ed tempe empera ratu ture res. s. . improves resistance to Copper atmospheric corrosion and, to a lesser extent, increases strength, with little loss in ductility; it adversely affects hot working working characteristics and surface quality.

Alloying Elements & Their Effects On The Properties of Steel

8. Lead

- impr improv oves es mach machin inab abil ilit ity; y; it causes liquid-metal embrittlement.

9. Magnesium -

has the same same effect as cerium cerium..

10. Manganese -

impro improvves harden hardenabi abilit lityy, strength, abrasion resistance, and machinability; it deoxidizes the molten steel and reduces hot shortness; and it decreases weldability weldability..


11. Molydenum -

impro improve vess harden hardenabi abilit lityy, wear resistance, resistance, toughness, toughness, elevatedtemperature strength, creep resistance, and hardness; it minimizes temper embrittlement.

12. Nickel -

impro improves ves stre streng ngth th,, toug toughn hnes ess, s, and corrosion resistance; it improves hardenability.

.


13. Nodium

- impa impart rtss fin fines esss of gr grain ain siz size and improves strength and impact toughness; it lowers transition temperature; and it may decrease hardenabilit hardenabilityy.

improvves streng strength, th, 14. Phosphorous - impro

hardenability , corrosion resistance and machinability; it severely reduces ductility and toughness. .

Alloying Elements & Their Effects On The Properties of Steel impro oves mac machi hina nabi bili lity ty . 15. Selenium - impr 16. Silicon - improv improves es strength, strength, hardness hardness,, corrosion resistance, resistance, and electrical conductivity; it decreases magnetic hysteresis loss, machinability machinability,, and cold formability.

17. Sulfur

improves machinability when combined with manganese; it lowers impact strength and ductility; it impairs surface surface quality and weldability -


18. Tantalum -

has has eff effects ects simi simila larr to thos thosee of

niobium.

19. Tellerium - -

improves machinabil mach inability ity,, formability formabil ity,, and toughness toughnes s

20. Titanium Titanium

improves hardenability; it deoxidizes steels. . -


21. Tungsten -

has the same effect of cobalt.

- 22. Vanadium

improves strength, toughness, abrasion resistance, and hardness at elevated temperatures; it inhibits grain growth during heat treatment.

23. Zirconium

-

has the same effects as

cerium.

Cerium - cont contro rols ls the the shap shape e of incl inclus usio ions ns and and impr improv oves es toug toughn hnes ess s in high high-s -str tren engt gth, h, lowlow-al allo loy y stee steels ls;; it deox deoxid idiz izes es stee steels ls..

Residual Elements in Steels 1. Anti ntimon mony 2.Oxygen 3.. Arsenic 4. Tin 5. Nitrogen

Nickel Alloys These are alloys used in variety of structural applications that usually require specific corrosion resistance and strength and toughness tough ness at temperature extremes as great as 2000 0F and as low as – 400 0F.

Titanium Alloys - These are non magnetic and extremely extremely corrosion resistance resista nce alloys. These hav h avee low thermal conductivity and outstanding in strength to weight weight ratios.

Zinc Alloys - These are alloys alloys whose whose melting melting temperatures are low. Its abundance made it more economical.

Common Uses of Alloy Steel

Common Uses Uses of Alloy Steel Steel

AISI - American Iron and Steel Institute

ASTM - American - American Society for Testing Testing and Materials

ANSI - American - American National Standards Institute

ASME - American - American Society of Mechanical Engineers

SAE - Society of Automotive Engineers

Low Melting Alloys

1. Lead

- has prope properti rties es of high high densit densityy, resistance resistance to to corrosio corrosion, n, softness, low strength, ductility ductility, and good workability workabilit y. Lead is used for damping damping sound and vibrations, in radiation shielding against Xrays, in ammunition, as a s weights, weights, and in the chemical industry.

Low Melting Alloys metal fourth fourth most most utilized utilized 2. Zinc - is the metal

industrially industr ially,, coming after iron, aluminum, aluminu m, and copper. It has two major uses: for galvanizing iron, steel sheet, and wire; and as an alloy base for casting.

3. Tin

- is an alloy alloying ing elemen elementt for for dental dental alloys and for bronze, titanium, and zirconium alloys. An ancient metal used in canning cannin g due to its resistance to rust and other corrosion.

Refrat Ref ratory ory Met Metal alss & Allo Alloys ys

1.

- is a silv silver-whit er-whitee metal, metal, was was discover discovered ed in the 18 th centuries. It It has a high melting point, a high modulus of elasticity elastic ity,, good resistance to thermal shock, shock, and good electrical and thermal conductivity. -

Used Used Used Used Used

in solid-propellant rockets & jet & jet engines, engines, in honeycomb structures, structures, in electronic componen components ts,, in heating elements, elements, in dies for die casting. casting.

Section III-A Jan. 19, 2017


- posse possess sses es good good ductility ductility and formability formabi lity,, and it has has greater oxidation resistance resista nce than other refractory metals.

- Used sed in roc ock kets ets and and mis missi siles les - Used Used in nuclear nuclear,, ch chemi emical cal,, and superconductor applications.

Refrat Ref ratory ory Met Metal alss & Allo Alloys ys 3. Tungsten

- is the the most plentiful plentiful of all the refract refractory ory metals. It has the highest melting melti ng point poin t of any metal and characterized by high strength at elevated temperatures. temperatures. It has high density, density, is brittle at low temperatures and offers poor p oor resistance resistance to oxidation.

-

for nozz nozzle le thr throa oatt line liners rs in in miss missililes es hotte hottest st par parts ts of of jet jet and and rock rocket et eng engin ines es,, circuit br breakers, welding ding el electr ectro odes, des, and and spar sparkk-pl plug ug ele elect ctro rode des. s.


4. Tantalum- -

is ch char arac actteriz erized ed by high igh melt meltiing point, good ductility du ctility,, and resistance to corrosion..

- Used Used as an allo alloy ying ing ele eleme ment nt,, - Used Used as as elec electr trol oly ytic tic capa capaci cito tors rs - Used Used in in var vario ious us com compo pone nent nts s in in the the electrical, electronic, and chemical industries; - Used Used also also for for ther therma mall appl applic icat atio ions ns,, such as in furnaces and in acidresistant heat exchangers

Special-Purpose of Steels - The material ial produced to meet certain certain special special conditions in in fabrication or in use such as free machining, heat resistance, corrosion resistance, impact resistance and tool steel.

HSLA Steels (High Strength Strength Low Alloy)- - A class of relatively low cost steels providing much m uch of the advantage or more costly regular alloys steels.

Case Hardening Steels - A steel hardening which is usually done in the material surface only. It is accomplished by carburizing, cyaniding, cyaniding, nitriding, induction hardening or flame hardening

High Speed Steel - It is an alloy of tungsten, chromium, vanadium and carbon. Most common composition is 18% tungsten, 4% chromium, 1% vanadium and 0.70% carbon. Sometimes cobalt up to 4% is added to improve its high speed quality. It is generally used for lathe, shaper, planer tools, drills and milling cutters.

Bright Steels - The main constituents of bright steel are 0.05 to 0.45% carbons and up to 0.20% lead. It is generally used for making bolts, set screws, pin etc. which are to be used for a long time for highly loaded parts.

Mild Steel (M.S)- - It contains 0.05% to 0.25% carbon. It is ductile, malleable, and easy for forging and welding and can be case hardened. It is used for general purposes to make wires, rods, sheets, flats, rounds angles, channels and other structural works.

High Carbon Steel - The main constituents of bright steel are 0.05 to 0.45% carbons car bons and up to 0.20% lead. It is generally used for making bolts, set screws, pin etc. which are to be used for a long time for highly loaded parts.

Stainless Steel (S.S)- - A kind of steel that contains a minimum m inimum of 10.5% chromium. Alloy steel which contains mainly chromium and nickel. A stainless steel contains 18% chromium, 8% nickel is mostly used. Another type of stainless steel containing 12 to 20% chromium, 8 to 12% nickel 1% manganese added with 1% of carbon steel. It is used for measuring and surgical instruments.

Stainlesss Steel (S.S) Family Stainles

Stainless Steel (S.S) Applications Ferrit Fe rritic ic Sta Stainl inless ess Ste Steel el 1. Atmospheric Atmospheric corrosion 2. Decorative 3. Elevated temperatures

Matenstic Stainless Steel 1. Structural components 2. Cutting devices 3. Tools

Stainless Steel (S.S) Applications Stainless Steel 1.Chemical resistance 2. Piping 3. Tanks

PH Stainless Steel 1. Structural members members 2. Springs

Cast Iron The most abundant and cheapest cheapest material. It It has four four element alloys containing iron, carbon, silicon and manganese. mangane se. A type of iron which contains 3 to 3.5% carbon either in combined form or in free state. Generally cupola furnace is used for the manufacturing of cast iron.

Properties of Cast Iron Iron 1. gray cast iron has gray structure 2. white cast iron has ssilver ilver white structure 3. it cannot be forged, bent or twisted 4. it can be easily cast into different shapes 5. gray cast iron can easily be machined 6. it is heat resisting and sensitive to shock. 7.it has high compressive strength

Gray Iron - A kind of iron primed primed from carbon that that is precipitated in the form of graphite flakes. It contains 2.5 to 3% carbon in combined form. It is very very hard and brittle and difficult to be machined.

Ductile Iron Iron (Nodular Iron) Iron) - It is an iron iron alloyed alloyed with magnesium which causes the excess excess carbon to precipitate in the form of small smal l spheres or nodules.

White W hite Iron Iron - An iron produc produced ed in outer portion of gray gray and ductile iron castings by chilling selected sele cted surfaces of the mold, thereby denying time for carbon precipitation. precipitation . It contains 2.5 to 3% carbon in combined form. It is very hard and brittle and difficult to be machined.

Malleable Iron Iron - An iron made from iron iron by a two-stage two-stage heat treating process. The structure promotes ductility, strength, and shock resistance.

To be continued in Module 4

REFERENCE REFER ENCE MA M ATERI TERIALS ALS 1. 2.

Kent’s Mechanical Engineers Handbook 12 th Edition,. Power Volume, Colin Carmichael, Ed Publisher: John Wiley & Sons Inc. 1950

3.

Marks Standard Handbook for Mechanical Engineers 10th Edition,. By, By, Eugene A. Avallon Avallonee and Theodore Theodore Baumester Baumester III Publisher: Publisher: McGraw Hill Book Co. Inc. 1997

4.

Mechanical Engineers Handbook 2nd Edition,. By, By, Miller Kutz, Ed. Power Publisher: John Wiley & Sons Inc. 1999

5.

Tool & Manufacturing Manufact uring Engineers Enginee rs Handbook Handboo k 3rd Edition,. Editi on,. By, By, Daniel Dallas Publisher: Society of Manufacturing Engineers

OTHER REFERENCES:

1.

http:/ http://ww /www w.spsu. .spsu.edu edu/me /met/s t/snass nasseri/ eri/too tooldes ldesign ign/SM /SME-to E-toold oldesi esigngnTOC.pdf --

2.

http:/ http://ww /www w.savep .savepdf. df.org org/fun /fundam dament entalsals-ofof-too tool-de l-desig sign-en-e-boo book/ k/

3. 4.

http://www.wisetool.com/deepdraw.htm www.webstatschecker.com/stats/keyword/computer_fundametals

5. www.spsu.edu/met/snasseri/tooldesign/SME-tooldesign-TOC.pdf 6.

http: ttp:// //lilibbra rary ry.t .thi hink nkqquest uest.o .org rg//

7.

http://mathforum.org/mathtools/sitemap.html

Materials Science Notes by Prof. Manuelito Radam

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