7/30/2019 Materials Behavior for Industry-Basics (2)

1/26

BASIC of MATERIALS SCIENCE

Steel

7/30/2019 Materials Behavior for Industry-Basics (2)

2/26

Material Content of a Car

Most cars weigh between 400 kg to 2500 kg.

Contributors to the weight of car

7/30/2019 Materials Behavior for Industry-Basics (2)

3/26

Fe: Iron

Iron is a chemical element with the symbol Fe(Latin: ferrum) and atomic number 26. It is a

metal in the first transition series. Like other

group 8 elements, it exists in a wide range ofoxidation states. Iron and iron alloys (steels)

are by far the most common metals and the

most common ferromagnetic materials in

everyday use. Fresh iron surfaces appear

lustrous silvery-gray, but oxidize in air.

wikipedia

http://en.wikipedia.org/wiki/Chemical_elementhttp://en.wikipedia.org/wiki/Latin_languagehttp://en.wikipedia.org/wiki/Atomic_numberhttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/First_transition_serieshttp://en.wikipedia.org/wiki/Group_8_elementhttp://en.wikipedia.org/wiki/Oxidation_statehttp://en.wikipedia.org/wiki/Alloyhttp://en.wikipedia.org/wiki/Steelhttp://en.wikipedia.org/wiki/Ferromagnetichttp://en.wikipedia.org/wiki/Ferromagnetichttp://en.wikipedia.org/wiki/Steelhttp://en.wikipedia.org/wiki/Alloyhttp://en.wikipedia.org/wiki/Oxidation_statehttp://en.wikipedia.org/wiki/Group_8_elementhttp://en.wikipedia.org/wiki/First_transition_serieshttp://en.wikipedia.org/wiki/Metalhttp://en.wikipedia.org/wiki/Atomic_numberhttp://en.wikipedia.org/wiki/Latin_languagehttp://en.wikipedia.org/wiki/Chemical_element

7/30/2019 Materials Behavior for Industry-Basics (2)

4/26

Steel Making

7/30/2019 Materials Behavior for Industry-Basics (2)

5/26

El Fe es un material alotrpico

Cambios alotrpicos BCC: body centered cubic

1538

1394

912

770 FCC: fase centered cubic

austenite

ferrite

Exothermic reactions when cooling

7/30/2019 Materials Behavior for Industry-Basics (2)

6/26

Phase Diagrams

WATER PHASE DIAGRAM

7/30/2019 Materials Behavior for Industry-Basics (2)

7/26

Cooling Curve solidification of pure metals

Cooling curve for thesolidification of pure metals.

Note that freezing takes placeat a constant temperature;during freezing the latent heatof solidification is given off.

7/30/2019 Materials Behavior for Industry-Basics (2)

8/26

Nickel-Copper Alloy Phase DiagramPhase diagram for

nickel-copper alloysystem obtained at aslow rate ofsolidification. Notethat pure nickel and

pure copper eachhas one freezing ormeltingtemperature. Thetop circle on theright depicts thenucleation ofcrystals. Thesecond circle showsthe formation ofdendrites (seeSection 10.2). The

bottom circle showsthe solidified alloy,with grain

boundaries.

7/30/2019 Materials Behavior for Industry-Basics (2)

9/26

Lead-Tin Phase DiagramThe lead-tin phase

diagram. Note thatthe composition ofthe eutectic pointfor this alloy is61.9% Sn-38.1%Pb. A compositioneither lower orhigher than thisratio will have ahigher liquidustemperature.

7/30/2019 Materials Behavior for Industry-Basics (2)

10/26

Diagrama Hierro-Carbono

Nombres comunes de las fases

Austenita

7/30/2019 Materials Behavior for Industry-Basics (2)

11/26

Aceros HipoeutectoidesMicrostructuras

7/30/2019 Materials Behavior for Industry-Basics (2)

12/26

Aceros Hipereutectoides

Microstructuras

7/30/2019 Materials Behavior for Industry-Basics (2)

13/26

Diagrama Hierro-Carbono

Hierro puro y Fe3C (6.67%C

en Fe)-compuesto intersticial.

Fe3C es una fase metastable

(se descompondra en Fe ygrafito)

7/30/2019 Materials Behavior for Industry-Basics (2)

14/26

Extended Iron-Carbon Phase Diagram

Figure 4.12 Phase diagram for the iron-carbon system with graphite(instead of cementite) as the stable phase. Note that this figure is anextended version of Fig. 4.8.

7/30/2019 Materials Behavior for Industry-Basics (2)

15/26

Microstructures for Cast Irons

(a) (b) (c)

Figure. Microstructure for cast irons. Magnification: 100X. (a) Ferritic gray iron with graphite flakes. (b)Ferritic Ductile iron (nodular iron), with graphite in nodular form. (c) Ferritic malleable iron; this cast ironsolidified as white cast iron, with the carbon present as cementite, and was heat treated to graphitize thecarbon. Source: ASM International.

7/30/2019 Materials Behavior for Industry-Basics (2)

16/26

Tensile-Test Specimen and

Machine(b)

(a) A standard tensile-test specimen before and after pulling, showing original and final gagelengths. (b) A typical tensile-testing machine.

7/30/2019 Materials Behavior for Industry-Basics (2)

17/26

Stress-Strain CurveA typical stress- strain curveobtained from a tension test,showing various features.

7/30/2019 Materials Behavior for Industry-Basics (2)

18/26

Mechanical Properties of Various Materials at

Room Temperature

TABLE 2.2 Mechanical Properties of Various Materials at Room Temperature

Metals (Wrought) E (GPa) Y (MPa) UTS (MPa)

Elongation

in 50 mm

(%)Aluminum and its alloysCopper and its alloys

Lead and its alloys

Magnesium and its alloysMolybdenum and its alloys

Nickel and its alloysSteelsTitanium and its alloys

Tungsten and its alloys

6979

105150

14

4145

330360

180214190200

80130

350400

35550

761100

14

130305

802070

10512002051725

3441380

550690

90600

1401310

2055

240380

902340

34514504151750

4151450

620760

454

653

509

215

4030

605652

257

0

Nonmetallic materialsCeramics

DiamondGlass and porcelain

Rubbers

ThermoplasticsThermoplastics, reinforced

Thermosets

Boron fibersCarbon fibers

Glass fibers

Kevlar fibers

701000

8201050

70-80

0.010.1

1.43.4250

3.517

380275415

7385

62117

1402600

140

78020120

35170

350020003000

35004600

2800

0

10005101

0

00

0

0

Note: In the upper table the lowest values for E, Y, and UTS and the highest values for elongation are for pure metals.

Multiply gigapascals (GPa) by 145,000 to obtain pounds per square in. (psi), megapascals (MPa) by 145 to obtain psi.

7/30/2019 Materials Behavior for Industry-Basics (2)

19/26

Loading and Unloading of Tensile-Test

Specimen

Figure Schematic illustration of theloading and the unloading of a tensile-test specimen. Note that, duringunloading, the curve follows a path

parallel to the original elastic slope.

7/30/2019 Materials Behavior for Industry-Basics (2)

20/26

Hardness TestsGeneral characteristicsof hardness-testingmethods and formulasfor calculatinghardness. The quantity

Pis the load applied.Source: H. W. Hayden,et al., The Structureand Properties of

Materials, Vol. III(John Wiley & Sons,1965).

7/30/2019 Materials Behavior for Industry-Basics (2)

21/26

Hardness

ConversionChart

Chart forconverting varioushardness scales.

Note the limitedrange of mostscales. Becauseof the manyfactors involved,these conversionsare approximate.

7/30/2019 Materials Behavior for Industry-Basics (2)

22/26

Demostration of various materials

http://www.wiley.com/college/callister/04701

25373/vmse/index.htm

7/30/2019 Materials Behavior for Industry-Basics (2)

23/26

Intro: Advanced High Strength Steels:

DP-Dual Phase Steels

7/30/2019 Materials Behavior for Industry-Basics (2)

24/26

Intro: AdvancedHigh Strength

Steels

Ultra Light SteelAuto Body

Project (ULSAB)

7/30/2019 Materials Behavior for Industry-Basics (2)

25/26

Intro: Advanced High Strength Steels

Ultra Light Steel Auto Body Project (ULSAB)

7/30/2019 Materials Behavior for Industry-Basics (2)

26/26

Intro: Advanced High Strength Steels