Optimizing Technological Parameters in Electrical Discharge Machining with Graphene-Coated Aluminum Electrodes for Enhanced Machining of Titanium Alloy: A Taguchi-TOPSIS Approach

Electrical Discharge Machining (EDM) employing coated electrodes represents a relatively unexplored research avenue, with limited published findings to date. The choice of coating material significantly influences the EDM machining process, directly impacting the adjustment of technological parameters. Consequently, an in-depth investigation into the optimization of technological parameters for EDM with coated electrodes is imperative, aiming to propel the practical application of this innovative technique. This study focuses on determining the technological parameters for EDM utilizing an aluminum (Al) electrode coated with graphene for machining titanium alloy (Ti-6Al-4V). The research addresses a multi-objective optimization problem, with Material Removal Rate (MRR) and Tool Wear Rate (TWR) serving as key quality indicators. The integration of the Taguchi method with the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) is employed to address the multi-objective nature of the optimization challenge. The obtained results pinpoint optimal process parameters as U = 55 V, I = 5 A, and Ton = 1500 µs, resulting in an MRR of 6.57 mg/min. An in-depth analysis and evaluation of the machined surface quality with the coated electrode under optimal conditions are conducted. The TOPSIS method emerges as a fitting solution for this multi-objective optimization problem, offering simplicity in its computational steps.