Multi objective optimization of wire electrical discharge machining on Inconel 718 using Taguchi grey relational analysis

Abstract

Inconel 718 one of the Superalloy which is a high performance material that possess special features such as better mechanical properties, creep strength, oxidation and corrosion resistance and thermal resistance and considered as a difficult to machine material because of its poor machinability by traditional machining methods due to its low thermal diffusivity and high strength. To overcome such kind of shortcomings, nontraditional approach of material removal processes have been developed and expected to be a suitable substitute method for traditional methods of machining. Wire Electrical Discharge Machining (WEDM) is one of the variant developed from the perception of Electrical Discharge Machining (EDM) process that is predominantly employed for machining of hard materials and also for making complex shaped components. In this present work, the machinability study on WEDM of Inconel 718 has been discussed with special attention on parametric optimization by Taguchi’s single response approach. The experimental runs are planned by Taguchi’s DoE approach. The experiments have been performed by considering the process variables such as pulse on time, pulse off time and peak current at three various levels. The ascendency of process variables are determined by ANOVA analysis. Taguchi - Grey methodology has been adopted for the WEDM process and combination of process variables are determined for accomplishing improved multi performance characteristics.