MSE 200 Assessment 2 Solved 100% Correct
Necking in the stress-strain curve is observed in the
a. engineering stress-strain
b. true stress-true strain
c. both a and b - ANS-a. engineering stress-strain
Yield strength is defined at an off-set plastic strain of
a. 0.02 b. 0.2 c. 0.002 - ANS-c. 0.002
In the elastic region, the true stress compared to the engineering stress in tension is
a. much higher b. much lower c. the same - ANS-c. the same
The yield strength of a material compared to the UTS is
a. higher b. smaller c. same - ANS-b. smaller
Engineering stress, although not the same as the true stress, is used in applications
because we usually limit the design to stay:
a. below the yield strength
b. at the yield strength
c. above the yield strength - ANS-a. below the yield strength
Poisson's ratio is:
a. usually positive b. usually negative c. usually about zero - ANS-a. usually positive
At an invariant point, the number of degrees of freedom are
a. 1 b. 2 c. 0 - ANS-c. 0
In a binary component metallic system, the phase rule is changed to
a. P+F=C+2 b. P+F=C+1 c. P+F=C - ANS-b. P+F=C+1
Coring is a result of
a. equilibrium cooling
b. finite cooling
c. gases evolved during cooling - ANS-b. finite cooling
The lamellar structure is formed in
a. Hypoeutectic alloy
b. eutectic alloy
c. hypereutectic alloy - ANS-b. eutectic alloy
Lever rule is applied in
a. single phase region b. two-phase region c. three-phase region - ANS-b. two-phase
region
Precipitates strengthen a material by:
a. increasing the grain size
b. pinning solute atoms
, c. impeding dislocation motion - ANS-c. impending dislocation motion
Fatigue damage is a result of
a. mean stress applied above the yield strength
b. stress concentrations developed that lead to intensify the stress beyond yield
point locally
c. material that becomes more plastic under alternating stress - ANS-b. stress
concentrations developed that lead to intensify the stress beyond yield point locally
Cold working
a. increases the dislocation content of a material, thereby decreasing strength
b. increases the dislocation content of a material, thereby increasing strength
c. increases the dislocation content of a material, thereby increasing ductility - ANS-
b. increases the dislocation content of a material, thereby increasing strength
Ductile failure
a. occurs with significant plastic deformation
b. is usually catastrophic
c. absorbs very little energy - ANS-a. occurs with significant plastic deformation
Complete the following: real materials will ______ fail at a stress less than their
expected ideal strength
a. never
b. sometimes
c. always - ANS-c. always
Types of fundamental dislocations in a crystal are
a. 2
b. 1
c. 3 - ANS-a. 2
Screw dislocations have
a. an extra half plane in a crystal
b. a spiral shaped crystal around it
c. a surface where atoms are out of regular positions - ANS-b. a spiral shaped
crystal around it
Defects directly responsible for plastic deformation are
a. dislocations
b. Schottky defects
c. interstitials - ANS-a. dislocations
Work hardening in metals is a result of
a. single slip
b. multiple slip
c. low density of dislocations - ANS-b. multiple slip
In metals, the Brinell Hardness is a measure of
a. ductility
b. yield strength
Necking in the stress-strain curve is observed in the
a. engineering stress-strain
b. true stress-true strain
c. both a and b - ANS-a. engineering stress-strain
Yield strength is defined at an off-set plastic strain of
a. 0.02 b. 0.2 c. 0.002 - ANS-c. 0.002
In the elastic region, the true stress compared to the engineering stress in tension is
a. much higher b. much lower c. the same - ANS-c. the same
The yield strength of a material compared to the UTS is
a. higher b. smaller c. same - ANS-b. smaller
Engineering stress, although not the same as the true stress, is used in applications
because we usually limit the design to stay:
a. below the yield strength
b. at the yield strength
c. above the yield strength - ANS-a. below the yield strength
Poisson's ratio is:
a. usually positive b. usually negative c. usually about zero - ANS-a. usually positive
At an invariant point, the number of degrees of freedom are
a. 1 b. 2 c. 0 - ANS-c. 0
In a binary component metallic system, the phase rule is changed to
a. P+F=C+2 b. P+F=C+1 c. P+F=C - ANS-b. P+F=C+1
Coring is a result of
a. equilibrium cooling
b. finite cooling
c. gases evolved during cooling - ANS-b. finite cooling
The lamellar structure is formed in
a. Hypoeutectic alloy
b. eutectic alloy
c. hypereutectic alloy - ANS-b. eutectic alloy
Lever rule is applied in
a. single phase region b. two-phase region c. three-phase region - ANS-b. two-phase
region
Precipitates strengthen a material by:
a. increasing the grain size
b. pinning solute atoms
, c. impeding dislocation motion - ANS-c. impending dislocation motion
Fatigue damage is a result of
a. mean stress applied above the yield strength
b. stress concentrations developed that lead to intensify the stress beyond yield
point locally
c. material that becomes more plastic under alternating stress - ANS-b. stress
concentrations developed that lead to intensify the stress beyond yield point locally
Cold working
a. increases the dislocation content of a material, thereby decreasing strength
b. increases the dislocation content of a material, thereby increasing strength
c. increases the dislocation content of a material, thereby increasing ductility - ANS-
b. increases the dislocation content of a material, thereby increasing strength
Ductile failure
a. occurs with significant plastic deformation
b. is usually catastrophic
c. absorbs very little energy - ANS-a. occurs with significant plastic deformation
Complete the following: real materials will ______ fail at a stress less than their
expected ideal strength
a. never
b. sometimes
c. always - ANS-c. always
Types of fundamental dislocations in a crystal are
a. 2
b. 1
c. 3 - ANS-a. 2
Screw dislocations have
a. an extra half plane in a crystal
b. a spiral shaped crystal around it
c. a surface where atoms are out of regular positions - ANS-b. a spiral shaped
crystal around it
Defects directly responsible for plastic deformation are
a. dislocations
b. Schottky defects
c. interstitials - ANS-a. dislocations
Work hardening in metals is a result of
a. single slip
b. multiple slip
c. low density of dislocations - ANS-b. multiple slip
In metals, the Brinell Hardness is a measure of
a. ductility
b. yield strength