Investigation of Material Removal Rate and Tool Wear Rate in Spark Erosion Machining of Al-Fe-Si Alloy Composite Using Taguchi Coupled TOPSIS Approach

Abstract

An Electrical discharge machining (EDM) process is most essential in the machining of hard and complex geometrical material which is difficult to machine by conventional machining technique. The EDM process parameters namely electrode material, pulse current, pulse-on time and pulse-off time are significantly influence the machining performance characteristics, such as material removal rate (MRR) and tool wear rate (TWR). Hence, in the present study, the influence of EDM parameters on the MRR and TWR are examined during machining of Al-Fe-Si alloy (AA8011) filled with 15 wt.% ZrO2 composite fabricated through stir casting route. The experimental work was performed according to the L27 (34) orthogonal array using Taguchi design of experiments (DOE). A Taguchi method and Technique for order of preference by similarity to ideal solution(TOPSIS) has been used to investigate the multiple performance characteristics with an objective to maximize the MRR and minimize the TWR. Moreover, analysis of variance (ANOVA) has been employed to bring out the influence of the EDM parameters associated with each performance characteristics. Main effect plot shows that, the maximum MRR with minimum TWR are obtained by the optimum level of parameters are electrode material of EN-8, pulse current at 15amps, pulse-on time at 900 μs and pulse-off time at 60 μs. From ANOVA analysis, electrode material and pulse current are the most influencing parameters on the MRR and TWR. Finally, the confirmation experiment was conducted to verify the prediction of the results attained by the optimum EDM parameters combination.