Numerical investigation of the effect of laser shock peening parameters on the residual stress and deformation response of 7075 aluminum alloy

Massive laser shot peening (LSP) is a promising surface modification technology to improve the properties of metallic materials. In this work, with the established FEM model, the dynamic propagation characteristics of stress waves by single round and square impact were investigated. The effect of three critical LSP parameters such as scanning patterns, overlapping rates and spot shape on the residual stress and the displacement deformation (U3) of 7075 aluminum alloy were further investigated under same spatial energy input. The simulation results were compared and validated with the reported research results. The spot shape has little effect on the residual stress field after a single impact while a better LSP treatment could be achieved by the massive square spot impact strategy. The snake scanning pattern was proved to be an optimized advancing pulse sequence compared with other two scanning patterns. The uniformity of compressive residual stress field and the displacement deformation (U3) curve were improved with the increase of overlapping rate.

Automated summary

This study investigated the effects of massive laser shot peening on metallic materials using a finite element model, focusing on the impact of scanning patterns, overlapping rates, and spot shapes on residual stress and displacement deformation. The results showed that a better treatment could be achieved with massive square spot impact, snake scanning pattern is an optimized pulse sequence, and increasing overlapping rate improves the uniformity of compressive residual stress field.