Multi-Characteristic Optimization in Wire Electrical Discharge Machining of Inconel-625 by Using Taguchi-Grey Relational Analysis (GRA) Approach

Abstract

Inconel 625 is a nickel-chromium based super-alloy which is mostly used in high end applications due to its excellent chemical and fabrication properties combined with high strength and outstanding corrosion resistance. Wire EDM is most commonly the used process for machining this material and gives high accuracy and precision in the machined parts. In this paper, an attempt is made to undertake an experimental investigation to optimize the input variables like pulse on time, pulse off time, peak current, and servo voltage in Wire EDM for achieving simultaneous optimization of cutting rate, surface roughness, dimensional deviation, and wire wear ratio. Taguchi's L9 orthogonal array with one replication has been used as an experimental design and then analysis of variance (ANOVA) has been applied to determine the significant parameters and their contributions on response variables. Taguchi method has been combined with grey relational analysis for multi-characteristic optimization. Finally, results are validated with the help of confirmation experiments.