Effect of Electrode Materials on Electric Discharge Machining of 316 L and 17 - 4 PH Stainless Steels

Abstract

Electric Discharge Machining (EDM) is one of the most efficiently employed non-traditional machining processes for cutting hard-to-cut materials, to geometrically complex shapes that are difficult to machine by conventional machines. In the present work, an experimental investigation has been carried out to study the effect of pulsed current on material removal rate, electrode wear, surface roughness and diameteral overcut in corrosion resistant stainless steels viz., 316 L and 17-4 PH. The materials used for the work were machined with different electrode materials such as copper, copper-tungsten and graphite. It is observed that the output parameters such as material removal rate, electrode wear and surface roughness of EDM increase with increase in pulsed current. The results reveal that high material removal rate have been achieved with copper electrode whereas copper-tungsten yielded lower electrode wear, smooth surface finish and good dimensional accuracy.