Research on Material Removal Mechanism of Micro-EDM in Deionized Water

As one of the most promising processing methods, the microelectrical discharge machining (micro-EDM) process is widely used in industrial production; however, the material removal mechanism of micro-EDM in deionized water has not been clarified due to scale effect. In this paper, the influence of discharge parameters on the discharge crater size was studied by means of a single-pulse discharge experiment using a resistor–capacitor circuit (RC circuit). The variation trend of the discharge crater size with open-circuit voltage and capacitance was discussed based on the experimental results. The results show that the diameter and depth of the discharge crater increases with capacitance and open-circuit voltage due to the increasing discharge duration and the energy density of the discharge plasma. The discharge energy increases with the increase of capacitance and open-circuit voltage, which causes more materials to melt and vaporize, leading to the crater volume becoming larger. This study has reference value for the further application of micro-EDM adopting deionized water as a dielectric.