Effect of imprinting times and stress annealing on warm laser shock imprinting

The rapid development of mechanical systems' miniaturization has expanded the demand for higher precision and performance micro formed parts. For improving the forming height and quality of formed parts, and studying the influences of the stress annealing and imprinting times on the forming as well as surface roughness (Sa) of the formed parts, this paper proposed a composite process of imprinting times and stress annealing on warm laser shock imprinting (WLSI) to realize the precision forming of the aluminium foil. In this research, the WLSI experiments were carried out with the imprinting temperature, imprinting times, and stress annealing treatment as variables. Subsequently, the forming height, surface roughness, and surface oxidation of the formed parts were measured, the loading-displacement curve were monitored, the transient deformation process induced by WLSI was divided four stages (deformation stage, rebound stage, vibration stage, and stable stage), and the residual stress distribution of the formed parts were simulated and analyzed by ABAQUS. Finally, the influences of the above three factors on the formed parts were discussed and explicated, and these results showed that the imprinting times and stress annealing can improve effectively the forming effect of WLSI.