Numerical modeling of residual stress induced by laser shock processing

Laser shock processing (LSP) is proving to be a competitive technology to traditional surface enhancement techniques in engineering products. The LSP develops a significant residual compressive stress deep into the surface of a metal alloy, which is beneficial for fatigue, wear and corrosion. In this paper, a comprehensive three-dimensional model is presented to predict the development, magnitude and distribution of residual stress field induced by LSP. In order to verify the FEA model, a benchmark simulation is performed verified with available experimental results. The predicted residual stress field for single laser shock processing is well correlated with experimental data. With the aid of the model, the influences of LSP parameters such as full width at half maximum (FWHM), power density, spot size, number of shots and overlapped shots have been analyzed. Some optimized parameters of LSP can be made by employing the presented models and results of the parametric investigations.