Optimization of wire electrical discharge machining process parameters on Inconel 690 superalloy via Taguchi technique

The research work deals with the improvement of wire electrical discharge machining process parameters for Inconel 690 super alloy. The goal of optimization is to achieve a maximum material removal rate (MRR) and a minimum surface roughness (SR). Brass wire is employed as the electrode, and Pulse on time (PON), Pulse off time (POF), Wire tension (Wt) and Wire feed (Wf) were selected as the process variables. The investigations were modelled based on Taguchi L16 orthogonal array. The results revealed that maximum MRR was obtained when PON=12 µs, POF=57 µs, Wf=6 m/min, Wt=9 g, and a minimum SR was obtained when PON=12 µs, POF=60 µs, Wf= 9 m/min and Wt=7 g. The optimum condition for machining by grey relational grade and its rank order method are found to be PON=12 µs, POF=59 µs, Wf=7 m/min and Wt=10 g. Whereas on using grey-Taguchi technique, the optimum parameters are found to be PON=12 µs, POF=58 µs, Wf=6 m/min and Wt=10 g. Analysis of variance was utilized to determine the input parameter's influence on the performance parameter and it was found that PON has high significance in maximizing the MRR and minimizing the SR.