Microgroove formation in thin copper by laser-induced cavitation bubble shock: numerical and experimental investigation

A laser-induced cavitation bubble shock forming technology is proposed for microgroove formation in thin copper. It is stamped by using the impact pressure generated by the laser breakdown of liquid. The impact-induced micro-formation of thin copper is studied by numerical simulation and experimentation. A finite-element model is developed, and the impact pressure created by laser-induced cavitation is measured to study the spatial distribution of impact pressure. The laser-induced cavitation process of the high-speed impact on thin copper is numerically simulated. The results of simulations are consistent with those of experiments, confirming the model's accuracy. The simulation is then used to study the dynamic formation and deformation behavior of the laser-induced cavitation impact of thin copper. The stress and thickness distributions during the formation of microgrooves in thin copper are also investigated. Furthermore, the influence of laser fluence and copper thickness on formation is studied. The results reveal that the high-speed impact forming of thin copper by laser-induced cavitation is due to three impact forces: a plasma shock wave, a cavitation shock wave, and a microjet, and this technology can be used to form thin metal walls.