Optimization of cardanol oil dielectric-activated EDM process parameters in machining of silicon steel

The current research uses Taguchi grey relational analysis to optimize the process parameters in micro electro discharge machining of silicon steel using nickel-coated brass (NCB) tool and waste cashew shell oil-activated water-based dielectric. The key goal of this study was to determine the most influencing process parameter, which had the greatest impact on material removal rate (MRR) and tool wear rate (TWR) while drilling silicon steel. Another goal was to optimize the micro EDM process parameters to achieve high MRR with reduced tool wear rate in coated tools. Using the electroless plating process, a 0.47 mm brass tool was coated with 0.5, 1.0, and 2 µm nickel; similarly, the dielectric medium was activated using 5, 10, and 15 wt.% of cardanol oil. The method parameters were optimized using an orthogonal array and a grey method. In the micro EDM drilling method, grey relational analysis was used to evaluate the most affecting parameters, such as gap voltage, coating thickness, and cardanol oil percentage. Due to the increase in electron transfer, the cardanol oil percentage was found to be the most influencing process parameter among others. At second, the gap voltage dominates the machining process. It is noted that the optimized process parameter was A₃B₁C₃, which had an MRR of 9.69 mm³/min and a tool wear rate (TWR) of 1.09 mm³/min, as well as a grey relational grade of 0.749. Thus, the grey relational grade value of confirmation experiment is increased by 2.04% over the predicted mean value of 0.734.