Mechanical Behaviour and Testing of Materials Mock Test 4

10%

Question 1 of 10

1. What is P-N stress for a dislocation of width 10b?

G/10²⁷

G/400

Question 1 of 10

Question 2 of 10

2. c/a ratio is highest for ______ and least for _____

Zr, Ti

Cd, Be

Hg, Be

Mg, Co

Question 2 of 10

Question 3 of 10

3. Which factor doesn’t promote fine grain structure?

Inoculating agents

Longer holding times at high temperature

Fast cooling rates

Mechanical vibrations

Question 3 of 10

Question 4 of 10

4. Which factor is not a reason of Frank-Read source immobile pinning sites?

Other solute atoms

Intersection with other dislocations

Solvent atoms

Second phase particles

Question 4 of 10

Question 5 of 10

5. Simple ionic crystals show no plastic deformation.

False

True

Question 5 of 10

Question 6 of 10

6. A dislocation of width 0, requires stress equal _____ to move.

Very less

Infinity

Shear modulus

Negligible

Question 6 of 10

Question 7 of 10

7. The plane passing through the twinning axis and separating the region of twinning from undeformed part is called ___ planes.

Slip

Close packed

Basal

Twinning

Question 7 of 10

Question 8 of 10

8. Which of the following statement is false?

Mechanical twins generate due to plastic deformation

Annealing twins occur during annealing heat treatment

Annealing twins are mostly observed in FCC metals

Annealing twins form in high stacking fault energy metals

Question 8 of 10

Question 9 of 10

9. Which metals can be cold worked to the largest extent?

HCP

BCC

FCC

Question 9 of 10

Question 10 of 10

10. The density of dislocations increases by an order of ____ in magnitude during deformation.

8-9

2-4

6-7

12-13

Question 10 of 10