Experimental Investigation and Improvement of Surface Finish Analysis on HCHCR AISI-D7 using EDM

Abstract

The need for high surface finish is always an important factor in engineering, non-traditional machining process have replaced traditional machining process in many industrial applications. Electrical discharge machining (EDM is one of the non-traditional machining process. Electrode wear rate, material removal rate and surface roughness plays major role in machining process in this study the Taguchi Optimization Technique, is used to optimize the parameters like Peak Current, Pulse on time and pulse of time in the EDM machine. The purpose of optimization in this study is to accomplish the maximum surface standard, material removal rate and electrode wear rate. In the study tool steel AISI D7 is used as the workpiece material and copper electrode is chosen as the tool material for machining of workpiece. The die electric used here is distilled water for better machining. Taguchi’s L9 Orthogonal array is used for the experimentation. The selected input parameters are the Pulse on time, Pulse off time and Peak Current. The other parameters like electrode gap and supply voltage are taken as the fixed parameters. After conducting each experiment the surface roughness of the work piece is determined using the contact profile meter, material removal rate and electrode removal rate by the weighing the workpiece and formula. The optimization values have been obtained for Surface Roughness, Electrode wear rate and Material removal rate by using Taguchi Optimization technique.