Experimental Investigation on Electrical Discharge Machining of Inconel 718 Material

Nickel-based alloys are attractive materials for industrial applications owing to their good mechanical properties and excellent resistance to corrosion and oxidation, even under extreme conditions. In this paper, the behaviour of an INCONEL 718 alloy has been studied using Electrical Discharge Machining (EDM). The Objective of this paper is to investigate the optimal set of control parameters such as current, pulse-on time, duty cycle and voltage in EDM process of Inconel 718 alloy using electrolytic copper electrodes to identify the variations in three performance characteristics such as Material Removal Rate (MRR), Electrode Wear (EW) and Surface Roughness (SR). Two methods, Design of Experiments, Taguchi Method – L9 Orthogonal Array, Grey Relational Analysis and Design Of Experiments, Response Surface Methodology - Central Composite Second Order Rotatable Design – Regressive Analysis And Modeling, Grey Relational Analysis, are used to find and compare the optimal set of control factors with their respective level for obtaining the desired responses. Same set of four control factors with three levels each are used for conducting experiments in both the methods. The desired responses are Maximum Material Removal Rate, Minimum Electrode Wear and Minimum Surface Roughness.