EXPERIMENTAL INVESTIGATION OF METAL REMOVAL RATE ON EDM FOR VARIABLE TOOL MATERIALS

The Electrical discharge machining is a widely used precision manufacturing process. The process involves a controlled erosion of electrically conductive materials by initiation of rapid and repetitive spark discharges between electrode tool and work piece, separated by a small gap of about 0.01 to 0.05mm known as spark gap. In the present work, copper and brass are used as tool materials and mild steel EN8 is used as work piece material. The process parameters selected are discharge current (Ip), pulse on time (Ton), pulse off time (Toff) over the response of metal removal rate (MRR). A full factorial design of experiments is used to find the influence of process parameters on metal removal ra te (MRR). The experiments are repeated using a copper and brass electrode and the main and interaction effects are plotted. From the experiments it was found that interaction of discharge current and pulse on time, Discharge current are the most influencin g factors using brass as electrode. If copper is used as electrode then interaction of discharge current and pulse on time, Pulse off time are the most influencing factors on MRR.