Experimental and numerical investigation of laser shock peening effects on residual stresses and fatigue life in hollow plate

Laser shock peening (LSP) process is a modern technology that can be used to improve fatigue life by inducing compressive residual stresses on the surface and along the thickness of peened parts.The aim of this study is to improve fatigue life of parts due to apply this process in order to generate compressive residual stresses (CRS) on samples with stresses concentration .The main objective of this paper is to investigate the effect of LSP parameters include scanning pattern and laser pulse energy on maximum compressive residual stress (MCRS) and depth of CRS around a hole in a 5mm thickness using both finite element technique and experimental results.The specimen material is AA7075-T6 .This material is used in the aerospace industry due to its high strength and high fatigue resistance. Slitting method is used to determine the residual stresses. The results show that elaborate application of LSP could efficiently be used for stress concentration points and improve fatigue strength.