Study on Residual Stresses Redistribution in Welded Joint in Shot peening process

Investigations illustrate that fatigue behavior, corrosion resistance and failure behavior are one of the most common results affected by residual stresses. The shot peening process which causes compressive residual stress (CRS), is one of the ways to improve the performance of industrial components, especially weld joints with tensile residual stress. In the present paper, numerical analysis of parameters of shot peening process on residual stress distribution is employed on pre-stressed specimen. On one hand, the numerical simulation of this process is investigated. On the other hand, the surface CRS and the effective parameters of this process, by simulating it on the welded specimen, are investigated on and around the welding region. In each section, numerical results were verified not only with former numerical investigations but also with building a proper empirical specimen and measuring the stresses experimentally. Results illustrate the decrease of tensile residual stress or increase of CRS on the surface of the pre-stressed specimen after shot peening process. Moreover, it shows that parameters of the shot peening process have a significant impact on final stresses in the specimen. Besides, based on the results the maximum CRS goes up by increasing the diameter and velocity of the shot.