Padmakar

Dr. Indraj Singh

Dr. Jaspal Singh Gill

Dr. Amrik Singh

Abstract

Present study is based to optimize the machining parameters of electric discharge machining (EDM) of super alloy NIMONIC 90. The main objective behind the present work is to get better metal removal rate (MRR) and surface finish (SR) under optimal conditions. The results of experimental study were validated using Taguchi and Grey Relational Analysis (GRA) method and found to be significant. It showed that MRR sharply increased with the increase on pulse on time and decreased with the decrease in pulse off time.SR also increased as pulse on time increases up to a middle value then SR started decreasing. Experimental run number 2 found to be more suitable for the maximum surface finish 3.66 (µm) compromising the MRR. It is worth mentioning that the experimental run number 7 is preferred for the applications oriented towards higher MRR of the order of 0.20 g/min compromising surface finish.

Keywords- Nimonic 90, Electric Discharge Machining, Taguchi, Grey Relational Analysis (GRA)