Polycrystalline simulation and experimental study of spatiotemporal anisotropy aluminum alloy irradiated by nanosecond laser

Abstract Revealing the mechanism of the interaction between nanosecond lasers and metallic materials is an important and challenging task. This paper focuses on model development and experimental studies of the interaction of AA6061 and nanosecond lasers in high-energy laser systems. A numerical model based on the secondary development of ABAQUS is developed for the irradiation of aluminum alloy specimens by nanosecond lasers with an energy density of 2 J/cm2. The model takes into account the spatiotemporal anisotropy of the laser irradiation, including the temperature dependence of the physical parameters, the inhomogeneous distribution of the material, and the differential laser ablation threshold at different positions. The results indicate that at an energy density of 2 J/cm2, the interaction of the laser and aluminum alloy is accompanied by thermal expansion, thermal melting, thermal ablation, and mechanical damage, which are randomly distributed in a circular area with a diameter of one-half of the facula. In addition, the experimental results obtained by laser targeting are consistent with the simulation results. This study provides a more accurate numerical model and experimental guidance for precisely revealing the interaction mechanism of the irradiation of metallic materials by high-energy nanosecond lasers.