Effect of Electrode Materials and Optimization of Electric Discharge Machining of M2 Tool Steel Using Grey-Taguchi Analysis

Abstract

Electric Discharge Machining (EDM) is one of the most efficient employed non-traditional machining processes for cutting hard-to-cut materials. .Modern ED machinery is capable of machining geometrically complex or hard material components. Heat treated tool steel, composites, super alloys, ceramics, etc. In the present work, an experimental investigation has been carried out to study the effect of pulsed current on Material Removal Rate, Electrode Wear Rate and surface roughness in M2 tool steel. The present material used for the work were Harden up to 62 HRC and then machined with electrode materials of copper and Tungsten copper (75:25 grade) with square section of 10×10 mm and 35 mm in length. Then in second part of present work optimization of output parameters such as Material Removal Rate (MRR) and Surface Roughness during electric discharge machining of M2 tool steel using Grey-Taguchi analysis with L9 Orthogonal Array has been done. The Result shows that Copper can be replacing by Tungsten Copper electrode. The results reveal that High Material Removal Rate and Depth have been achieved with Tungsten copper electrode at process parameters Discharge current 15A, Pulse on time 45µs, pulse off time 9µs and Spark gap of 20µm and for Surface Roughness at Discharge current 5A, Pulse on time 15µs, pulse off time 6µs and Spark gap of 20µm using Taguchi approach, whereas using Grey Relational Analysis approach shows best result at Discharge current 15A, Pulse on time 15µs, pulse off time 9µs and Spark gap of 20µm.