Uniformity of residual stress distribution on the surface of S30432 austenitic stainless steel by different shot peening processes

Compressive residual stress induced by shot peening can effectively improve the fatigue resistance of the treated component. Much attention has been paid to increase the compressive residual stress value, and the uniformity of residual stress distribution was often ignored, which was also very important for improving the fatigue resistance. In this paper, the uniformity of compressive residual stress distributions on the surface of S30432 austenitic stainless steel after three different shot peening treatments has been investigated by X-ray diffraction method. The results revealed that compared with traditional shot peening, multi-step shot peening (dual shot peening, triple shot peening) methods can not only increase the stress value but also make the stress distribution more uniform.

► Uniformity of residual stress distribution on the surface of S30432 austenitic stainless steel after shot peening was investigated by X-ray stress analysis.
► Multi-step shot peening could improve the uniformity of residual stress distribution.
► The parameter to evaluate the uniformity of residual stress after shot peening was established.