Three-dimensional FEM analysis of laser shock peening of aluminium alloy 2024-T351 thin sheets

Laser shock peening is a relatively recent technique that introduces compressive residual stresses in metallic structures, improving fatigue, corrosion and wear resistance of treated materials. The purpose of this work is to evaluate numerically the effect of laser shock peening on thin sheets, since most of the numerical analyses available in the literature deal with semi-infinite body assumption, which disregards the reflection of shock waves from the back side of the treated specimen. This phenomenon should be considered when dealing with sheets used for thin walled constructions, for cases in which there is no possibility of using the back-up support, a solid plate in the contact with the backside of the treated sample that limits the wave reflection and deformations. Different set-ups of laser shock peening process are evaluated and an optimal set of parameters is suggested for a possible real structure application.