Q.1
The grain boundary sliding is promoted by increasing ____________ and decreasing ___________
  • a) temperature, strain rate
  • b) strain rate, temperature
  • c) temperature, stress
  • d) stress, temperature
Q.2
The material with low stacking fault energy is prone to sub-grain formation compared to the metal with high stacking fault energy.
  • a) True
  • b) False
Q.3
The grain boundary sliding is a shear process occurring along the ________
  • a) direction of the grain boundary
  • b) perpendicular direction of the grain boundary
  • c) outward plane of the grain boundary
  • d) inward plane of the grain boundary
Q.4
The total strain in the material is%. Find the approximate percentage of strain which is caused by grain boundary sliding in total deformation?
  • a) 47%
  • b) 40%
  • c) 5%
  • d) 0.01%
Q.5
The dislocation glide is one of the mechanisms responsible for creep of the metals. Its condition for dislocation mechanism is _______________
  • a) high stress
  • b) low stress
  • c) high temperature
  • d) low temperature
Q.6
The dislocation creep mechanism is active in the region ___________, where σ is applied stress and G is shear modulus.
  • a) σ/G > 10-2
  • b) 10 > σ/G > 10-2
  • c) 10-4 < σ/G < 10-2
  • d) σ/G < 10-4
Q.7
The diffusional creep is the chief mechanism activated in the stress range of ___________
  • a) σ/G > 10-2
  • b) 10 > σ/G > 10-2
  • c) 10-4 < σ/G < 10-2
  • d) σ/G < 10-4
Q.8
The chief mechanism responsible for Nabarro-Herring creep is _____________
  • a) dislocation glide
  • b) dislocation creep
  • c) diffusional creep
  • d) grain boundary sliding
Q.9
The chief mechanism responsible for Coble creep is _____________
  • a) dislocation glide
  • b) diffusional Creep
  • c) dislocation creep
  • d) grain boundary sliding
Q.10
The metal undergoing creep operates under only one creep mechanism at a time.
  • a) True
  • b) False
0 h : 0 m : 1 s