Optimization of EDM process parameters using Taguchi method

Abstract

This paper presents investigation and optimization of Electric Discharge Machining (EDM) parameters using Taguchi method. Three process parameters chosen were Pulse on-time (Ton), Duty factor and Discharge current (or pulse current). An L27 orthogonal array was selected to study the effect of main factors and interaction between factors on the response variable i.e. surface roughness. Signal to Noise (S/N) ratios of the response variable for all experiments were calculated. The contribution of the main factors and interaction between them to the optimal surface roughness were determined by using Analysis of Variance (ANOVA). The experimental results revealed that pulse-on time of 10 μs, duty factor of 7 and discharge current of 6 A yielded the optimal i.e. minimum surface roughness. Further, results of ANOVA indicated that out of three main factors, discharge current and out of three two way interactions, interaction between duty factor and discharge Current as well as interaction between pulse on-time and duty factor contributed significantly in minimising the surface roughness.