MULTI-RESPONSE OPTIMIZATION OF PROCESS PARAMETERS OF GREEN ELECTRICAL DISCHARGE MACHINING ON AISI 2507 SUPER DUPLEX STAINLESS STEEL USING GREY RELATIONAL ANALYSIS (GRA)

This research presents a performance analysis and investigation on eco-friendly Pongamia green dielectric (GD) with a pure copper tool electrode in the electrical discharge machining (EDM) of AISI 2507 super duplex stainless steel. The multi-response optimization of the EDM process parameters like pulse-on time (TON), pulse-off time (TOFF), peak current (IP), voltage (v) and inter-electrode gap (IEG) on the material removal rate (MRR), electrode wear rate (EWR) and surface roughness (SR) on the EDM of AISI 2507 super duplex stainless steel using grey relational analysis was examined. The Taguchi's design based L27 orthogonal array (OA) was employed for experimentation, and then investigated the optimal levels with grey relational analysis (GRA). Experimental results were analyzed statistically by analysis of variance. Surface and sub-surface cracks are analyzed by scanning electron microscopy. The optimal levels achieved by GRA were TON=400μs, TOFF=60μs, IP=21A, v=50V, and IEG=60μm.