Study on 2-D shock wave pressure model in micro scale laser shock peening

Laser-induced shock pressure in micro scale laser shock peening (mu LSP) is the key to numerically analyze the strengthening effect of the targets. In order to establish the model of shock wave pressure loading in mu LSP process, a reasonable simplification was conducted according to the shock wave propagation theory. 2-D pressure distribution along the radial and axial direction at different time was modeled based on theory of ellipsoidal wave propagation, comprehensively considering properties of shock wave propagation in time and spatial distribution and geometric features of ellipse. Numerical simulations of mu LSP with single point under 1-D and 2-D pressure loading were carried out to investigate the influence of loading in radial direction on residual stress distribution. The results showed that residual stress distribution under 2-D pressure loading was obviously different from the 1-D case, so effect of pressure in radial direction during the propagation of shock wave should not be ignored in mu LSP process. 2-D shock wave pressure model lays a theoretical basis for accurate loading of shock wave pressure in the simulation of mu LSP.