midterm 2

Question 1

modulus of elasticity

Answer 1

slope of the line or ratio of stress to strain while deformation is elastic
a measure of the material’s stiffness

Question 2

yield strength

Answer 2

maximum stress handled at a very slight and specific amount of plastic deformation
graphed a 0.02% offset from curve

Question 3

tensile strength

Answer 3

the maximum stress that can be sustained, in tension (under an axial load) without fracture

Question 4

ductility

Answer 4

the range of the curve
the ability to undergo appreciable plastic deformation without fracture

can be expressed as %EL (percent elongation) or %RA (%reduction in area)

Question 5

modulus of resilience

Answer 5

maximum energy absorbed by the material before plastic deformation

Question 6

toughness

Answer 6

the total area under the curve
the amount of energy absorbed by a material up to the point of fracture

Question 7

hardness

Answer 7

a measure of resistance to localized plastic deformation, resistance to surface deformation, indentation, or penetration

Question 8

stress/strain calculation with youngs modulus

Answer 8

youngs modulus = stress/strain
E= σ/ε

Question 9

stress calculation

Answer 9

stress= force/area
σ=F/A

Question 10

strain calculation

Answer 10

ε=△L/L0