Machining properties of micro EDM using electrostatic induction feeding

The purpose of this research is to develop a micro electrical discharge machining method using electrostatic induction feeding. With this method, a pulse generator is coupled with a tool electrode by a capacity in order to reduce the minimum discharge energy per pulse eliminating the influence of the stray capacitance in the circuit. Since both straight polarity discharge and reversed polarity discharge occur alternately, the tool electrode wear is high. Hence, in this study, a diode was connected between the tool electrode and the workpiece in parallel to the working gap to make the discharge unipolar. Theoretical analysis and experimental investigation were conducted on the discharge circuit which was modified to obtain the unipolar discharge.