Studies on Micro-Electrical Discharge Machining of Steel Using Copper Electrodes

Electrical Discharge Machining (EDM) is one of the non-conventional machining processes used for machining of electrically conductive materials. Mechanism of material removal in EDM is based on conversion of electrical energy into thermal energy. In this paper, copper electrodes of diameter 0.1, 0.4 and 0.8 mm were used for machining holes on steel work-piece to a depth of 0.2 mm by micro-EDM process. Experiments were conducted at a capacitance of 0.001, 0.01, 0.1 and 0.4 μF with a gap voltage of 80 V and the electrode was rotated at 100 rpm during ED machining. Wear on the electrode; surface roughness and the size of the machined hole were measured. Capacitance had a profound influence on the material removal rate, volumetric wear ratio, spark gap and surface roughness of work-piece.