GATE Physical Metallurgy: Crystal defects and interfaces – Previous Year Questions

6 GATE previous year questions on Crystal defects and interfaces (Physical Metallurgy, Metallurgical Engineering) with answers and explanations, from every paper.

1. GATE 2021 MT Q35 (1 mark, Numerical answer) – A crystal’s vacancy concentration doubles when temperature increases from 27 °C to 127 °C. Vacancy-formation enthalpy is kJ/mol (two decimal places).…
2. GATE 2021 MT Q41 (2 marks, Multiple choice) – Without external stress, which statement about point-defect/dislocation interaction is FALSE?
3. GATE 2022 MT Q50 (2 marks, Numerical answer) – Consider a tilt boundary of misorientation of 2୭in an aluminium grain. The lattice parameter of aluminium is 0.143 nm. The spacing between the…
4. GATE 2023 MT Q29 (1 mark, Multiple select) – The condition(s) for high degree of mutual substitutional solid solubility for two metals is/are
5. GATE 2024 MT Q53 (2 marks, Numerical answer) – For element A, vacancy-formation enthalpy and entropy per vacancy are 0.5 eV and 3k B. Its equilibrium vacancy mole fraction at 500 K is 10-4 (two…
6. GATE 2025 MT Q13 (1 mark, Multiple choice) – Match each crystal defect in Column I with its corresponding type in Column II. Column I: P. Edge dislocation Q. Stacking fault R. Frenkel defect S.…