The GATE Grind

GATE 2024 MT – Question 25

Mechanical Behaviour of Materials · Dislocations and strengthening · 1 mark · Multiple choice

Match the concepts in Column I with phenomena in Column II.

Column I:

P. Peierls–Nabarro stress

Q. Cottrell’s atmosphere

R. Paris law

S. Considère’s criterion

Column II:

1. Yield point phenomenon

2. Fatigue

3. Dislocation glide

4. Onset of necking

  1. P – 1, Q – 2, R – 3, S – 4
  2. P – 4, Q – 1, R – 2, S – 3
  3. P – 3, Q – 1, R – 2, S – 4
  4. P – 3, Q – 4, R – 2, S – 1

Practise this question in The GATE Grind →

Show answer and explanation

Correct answer: (C) P – 3, Q – 1, R – 2, S – 4

Explanation

Peierls–Nabarro stress is lattice resistance to dislocation glide (P3).

Cottrell atmospheres pin dislocations and produce yield-point behaviour (Q1).

Paris law describes fatigue crack growth (R2).

Considère’s criterion marks tensile necking (S4).

Therefore **C**.