Laser shock micro-sheet bulk metal forming: numerical simulation and experimental validation

In this study, a new method of laser shock micro-sheet bulk metal forming (LSMSBMF) is proposed in combination with the advantages of near-net sheet forming and laser shock forming. This method not only owns the advantages of high-speed loading, uniform material flow and die filling, but also is suitable for micro-forming. Based on a combination of experiment and numerical simulation, the influence of different laser energy loadings on the forming depth of micro-turbine is studied, and the material flow, stress wave propagation process and inertia effect during LSMSBMF forming process are further analyzed. The results reveal that micro-turbine gear tooth forming depth increases with the increase of laser energy, but the rate of increase slows down. By analyzing the material flow inside the workpiece in the forming process, it can be found that laser shock can improve the formability and material flow uniformity of the workpiece. At the same time, the smoothness of workpiece formation can be improved under the restriction of micro-die cavity. By studying the propagation of stress wave, it is found that elastic wave propagates faster than plastic wave at the beginning of this process, and the micro-turbine is formed by inertia filling the micro-die cavity.