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GATE 2023 MT – Question 22

Mechanical Behaviour of Materials · Creep · 1 mark · Multiple choice

The mechanism of creep for a single crystal as depicted in the schematic is

Diagram for GATE 2023 MT question 22
  1. Nabarro-Herring creep
  2. Grain boundary sliding
  3. Dislocation creep
  4. Coble creep

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Show answer and explanation

Correct answer: (A) Nabarro-Herring creep

Explanation

The diagram shows stress-driven vacancy flux through the crystal, with opposite atomic mass flux that elongates the crystal along the tensile direction. This is lattice-diffusion-controlled **Nabarro–Herring creep, A**. Coble creep instead uses grain-boundary paths.