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Iron is taken from the earth and copper is smelted from ore.Man puts an end to the darkness;

he searches the farthest recesses for ore in the darkness.The Bible (Job 28:2-3)

Image: Iron flows from a blast furnace. Source:American Iron and Steel Institute.

Figure 3.5 Stress-strain diagram for a ductile material.text reference: Figure 3.5, , page 96

A

P

P

(

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text reference: Figure 3.6, page 97

Figure 3.1 Ductile material from a standardtensile test apparatus. (a) Necking; (b) failure.

text reference: Figure 3.1, page 90

0

0

=

l

llEL

fr

%EL

Manifest

danger

stress concentrations

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Figure 3.2 Failure of a brittlematerial from a standard

tesiletest apparatus.

text reference: Figure 3.2, page 91

%EL%EL

text reference: Figure 3.7, page 98

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text reference: Figure 3.8, page 99

Figure 3.10 Stress-strain diagram for polymer below, at, and above its glass transitiontemperature Tg.

text reference: Figure 3.10, page 101

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=E

uniaxial

linear

Esteel

Ealum

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yx yx

torsion

=G

yx

x

y

steel

alum v

rubber vG E

transverse

axial

=

( )+=

EG

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yield

Allowable building

yallowy SS

yallow S=

yallowy SS

yallow S=

=

y

dUr

0rupture

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Class Members Short nameEnginering alloys(themetals and alloys ofengineering)

AluminumalloysCopper alloysLead alloysMagnesiumalloysMolybdenumalloysNickel alloysSteels

Tin alloysTitaniumalloys

Tungsten alloysZinc alloys

Al alloysCu alloysLead alloysMg alloysMo alloysNi alloysSteels

Tin alloysTi alloys

W alloysZn alloysEngineering polymers(thethermoplastics andthermosets of engineering)

EpoxiesMelaminesPolycarbonatePolyesterPolyethylene, high densityPolyethylene, low densityPolyformaldehydePolymethylmethacrylatePolypropylenePolytetrafluoroethylenePolyvinyl chloride

EPMELPCPESTHDPELDPEPFPMMAPPPTFEPVC

Engineering ceramics(fineceramics capableofload-bearing application)

AluminaDiamondSialonsSilicon carbideSilicon nitrideZirconia

Al2O3CSialonsSiCSi3N4ZrO2

Table 3.7 Material classesand members and shortnames of each member.[From Ashby (1992)].

text reference: Table 3.7, page 123

RA RB RC

SU HB HBSU HB

HB

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Charpy Izod

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quenching

critical temperature

below critical temperatureand

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carburizing

hardness

strength

hardness toughness

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Expensive!

y

y

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Brass zinc

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Figure 3.4 Cross section of fiber reinforcedcomposite material.

text reference: Figure 3.4, page 95

Figure 3.3 Strength/density for various materials.

text reference: Figure 3.3, page 94