Metal micro-hole formation without recast layer by laser machining and electrochemical machining

Laser machining and electrochemical machining (LM-ECM) of metal micro-hole is presented in this study. Millisecond pulsed laser etches metallic materials by thermal effect, and electrochemical machining removes recast layer. No recast layer is produced on the wall of metal micro-holes. Machining accuracy and efficiency are improved. Prefabricated micro-hole modeling of laser machining and metal micro-hole modeling of electrochemical machining are established. The main process parameters of LM-ECM are determined by the models. Effects of the process parameters on experimental results are investigated and the optimized parameters are given. Comparison between LM-ECM and single machining approaches is made. The experimental results revealed that the material surface of LM-ECM is cleaner than single laser machining and do not have molten slag. There is no recast layer on the wall of the micro-holes. Compared to single electrochemical machining, the efficiency and accuracy of LM-ECM are improved by 51.35% and 30.43% respectively.