Design & Manufacturing Test 1 (Ch. 1-2)

Front 1

Equation for Engineering Stress

Back 1

O = P/A

Front 2

Equation for Engineering Strain

Back 2

e = ( l - l_ ) / l_

Front 3

When does plastic deformation begin

Back 3

Yield Stress (Y)

Front 4

What is UTS

Back 4

The maximum ENGINEERING stress

Front 5

Modulous of Elasticity

Back 5

Ratio of Stress to Strain
(E = (O/e))

Front 6

True Stress

Back 6

O = P/A

Front 7

True Strain

Back 7

3 = ln ( l / l_ )

Front 8

True Stress True Strain Curve

Back 8

O = K3^n

Front 9

what is n (strain hardening coeficcient)

Back 9

True Strain and onset of necking

Front 10

Excess of Electrons is ____
Too few electrons is _____

Back 10

Negative Anion
Positive Cation

Front 11

Body Centered Cubic (bcc)
Slip Systems
b/a ratio
properties

Back 11

Has one central atom, shares eigth of an atom on 8 corners. 48 slip systems. High b/a ratio. High sheer stress required; good strength and moderate ductility

Front 12

Face Centered Cubic (fcc)
Slip Systems
b/a ratio
properties

Back 12

half an atom on 6 faces and eighth of an atom on 8 corners for total of 4. 12 slip systems, low b/a ratio low shear stress required; moderate strength good ductility

Front 13

Hexagonal Closed Pack (hcp)
slip systems

Back 13

densley packed 3 slip systems, brittle at room temp. Top and botum planes called basal planes

Front 14

allotorpism (polymorphism)

Back 14

the appearence of more than one type of crystal structure

Front 15

Anisotropy

Back 15

Single crystal exhibits diff properties when tested in diff directions

Front 16

Dislocations

Back 16

Linear or one dimensional defects

Front 17

Work Hardening

Back 17

Increase in sheer stress required to overcome entanglements and impediments that resul in increased strength and hardness
cause by dislocation engtanglement and disloaction impediments

Front 18

Nucleation Rate

Back 18

rapid cooling
High --- grains/unit volume large, grain size small

Front 19

Crystal Growth Rate higher than nucleation rate

Back 19

If higher than nucleation rate;
fewer grains/unit volume, grain size large

Front 20

isotropic

Back 20

properties do not vary with direction, such as polycrystaline metals

Front 21

Grain Size effects

Back 21

Large grain size--> low strength, low hardness, low ductility

Front 22

Hot Shortness

Back 22

Melting of impurities inside metal at temp lower than metal melting point

Front 23

Mechanical Fibering

Back 23

alignment of inclusions, impurities, and voids

Front 24

Annealing:
3 steps

Back 24

Heating a metal to a specific ranger over time:
a) recovery occurs below recrystalization temp
b)recrystalizaition new strain free grains replace older grains
c)Grain Growth occurs at temps above recrystalization temp

Front 25

Cold Working

Back 25

Plastic deformation carried out at room temp

Front 26

Hot Working

Back 26

Deformation occuring above recrystalization temp

Front 27

Warm Working

Back 27

Deformatioun carried out inbetween cold and hot working

Front 28

Increase temp on stress strain curve:

Back 28

increase in ductility and toughness
decrease in yield stress and modulous of elasticity
n decreases

Front 29

Deformation rate vs Strain Rate

Back 29

Deformation rate is the rate that a tension test is being carried out. Strain rate is a function of length

Front 30

Barreling

Back 30

When a specimens clindrical surface bulges due to friction in compression test

Front 31

Bauschinger Effect

Back 31

Also known as strain softening and work softening, hen a metal is subjected to tension into the plastic range and the load is then released and compressionis applied, the yield stress in compression is lower than that in tension

Front 32

Bending (Flexure)

Back 32

three or four point; top subjected to compression lower surface subjected to tension

Front 33

Hardness

Back 33

Resistance to permanent deformation

Front 34

Hardness Tests

Back 34

Brinell: steal or tungston-carbide ball
Rockwell: SImilar to brinell but two load applied and diff in depth calculated
Vickers: Pyramid shaped diamond indento
Knoop: similar to vickers but is a microhardness test

Front 35

Endurance Limit

Back 35

Maximu stress a material can be subjected to without fatigue faliure. Steels have endurance limit, many alloys dont

Front 36

Creep

Back 36

Permanent elongation of a component under a static load over a period of time

Front 37

Stress Relaxation

Back 37

Stress resulting from loading of a component over time decrease (guitar strings)

Front 38

Impact Tests

Back 38

Charpay Test: Supported at both ends
Izod Test: Supported at one end

Front 39

Ductile Fracture

Back 39

Plastic deformation preceeding failure, takes place along planes in which shear stress is max

Front 40

Transition Temp

Back 40

A narrow range of temp where materials undergo a shapr change in ductility and toughness.
Usually occurs in bcc and some hcp

Front 41

Strain Aging

Back 41

phenomenon in which carbon atoms in steel segregate to disloactions rulting in increased strength and reduced ductility

Front 42

LIst 4 ways to improve fatigue strength

Back 42

1) inducing compressive residual stresses
2) case hardening
3)providing a fine surface finish
4) ensuring materials are free of inclusions

Front 43

What to tensile residual stresses cause

Back 43

Stress corrosion cracking