Question

Cold cracking failure of the casting product can be avoided by shot peening method which induces internal stresses in the casting.

(a) True

(b) False

This question was posed to me during a job interview.

Question is taken from Residual Stress in chapter Cooling and Solidification of Casting-Forming-Welding I

Answer 1

Correct option is (b) False

The best I can explain: Cold cracking is basically caused by residual stresses exceeding the limitation of the casting’s strength. It normally appears at the tensile sites of the castings, especially at the sites of stress concentration. Shot peening method, instead of avoiding this defect, it increases the chances of cold cracking by inducing more stresses into the casting product.