1022. Mechanism/phenomenon involved in the improvement of fatigue strength of a material by shot peening is the

A. Induction of residual compressive stress on the surface
B. Removal of stress concentration from the surface
C. Grain refinement
D. Surface polishing
✅ The correct answer is option A.

1024. Which of the following hardness tests uses the depth of penetration caused by the indentor as the parameter for arriving at the hardness value of a material ?

A. Shore sceleroscope test
B. Vicker’s hardness test
C. Brinell hardness test
D. Rockwell hardness test
✅ The correct answer is option D.