The tendency of material to fracture without appreciable deformation is called
c. Brittleness
Statement A: Brittle material is strong in compression but weak in tension. Statement B: Ductile material is approximately equally strong in tension and shear, but weak in compression.
a. Only Statement A is correct
The ability of a material to absorb energy within the elastic region is called
c. Resilience
Which portion of the creep curve provides the information on steady-state creep rate?
b. Secondary stage
A good malleable material possesses
b. high degree of plasticity
Engineering strain of a mild steel sample is recorded as 0.100%. The true strain is
c. 0.099%
Under torsion, brittle materials generally fail
d. along the surface forming a 45° angle with a longitudinal axis
In tension failure of a brittle metal, failure plane is at ______ degrees
a. 90
If a material is subjected to two incremental true strains namely ε₁ and ε₂, then the total true strain is
c. ε₁ + ε₂
True stress–strain curve needs to be corrected after
c. Tensile strength
Following condition represents onset of necking
a. ε₀ = n
Time-dependent recoverable deformation under load is called ______ deformation.
a. Anelastic
Strain hardening exponent indicates the response to cold work i.e., larger n means
a. greater strain hardening for a given amount of plastic strain
A steel rod is pulled in tension with a stress less than yield strength. The modulus of elasticity may be calculated as
a. Axial stress divided by axial strain
Plastically deforming a metal specimen near room temperature generally leads to
a. increased tensile strength and decreased ductility
A dislocation formed by adding an extra half-plane of atoms to a crystal is referred to as
d. edge dislocation
Atoms surrounding a screw dislocation experience which kinds of strains?
D. Shear strains and compressive strain
What is the process of heating metal in furnace to slightly above upper critical temperature and cooling slowly in the furnace?
d. Annealing
Which of the following is a strengthening mechanism?
C. strain hardening
Macroscopic plastic deformation corresponds to the motion of
a. large numbers of dislocations, ability of metal to plastically deform depends on ability of dislocations to move
Increasing the percentage of cold work
c. increases the rate of recrystallization
Recrystallization is the formation of
a. a new set of strain-free equiaxed grains with low dislocation density, characteristic of pre-cold-worked condition
Compute grain diameter when same original material is heated for 5.5 h at 500°C.
b. 1.23x10^-4mm
You are given two wires W1 and W2, same material, same length. Cross-section radius of W2 is twice that of W1. Same load is applied. If strain in W1 is 4, calculate strain in W2.
d. 1
