Electric Discharge Machining is a non-conventional machining process, used to machining difficult to machine materials. The major problem faced while doing EDM is high Electrode wear rate, surface roughness and low material removal rate. In this research work experimental investigations have been made to find the machining characteristics of different electrode like copper, graphite, copper tungsten and brass on Inconel 718 super alloy. The present paper presents the effects of peak current and pulse on-time(Ton) on the output parameters like Material Removal Rate(MMR), Electrode Wear Rate(EWR) and Surface Roughness(SR).

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Electrical Discharge Machining (edm) Material Removal Rate (mrr) Electrode Wear Rate (ewr) Surface Roughness (sr)