Optimization of wire electrical discharge machining process parameters on material removal rate for Al7075/SiC/Al^sub 2^O^sub 3^ hybrid composite

This article investigated the effect of wire electrical discharge machining process parameters such as pulse on time, pulse off time, pulse current and the wire drum speed on the material removal rate, while machining newly developed hybrid metal matrix composite (Al7075/7.5%SiC/7.5%Al2O3). The hybrid composite was prepared by inert gas-assisted electromagnetic stir casting process. Taguchi method was used for parameter optimization and the level of importance was determined using analysis of variance. The results showed that pulse on time, pulse off time and pulse current were significant parameters. The pulse on time was the most significant parameter that contributed maximum (46.04%) to the material removal rate followed by pulse current (34.72%), pulse off time (10.23%) and interaction, pulse on time x pulse off time (5.46%). The wire drum speed had insignificant effect on the material removal rate. In confirmation test, the average experimental value of material removal rate was within the predicted optimum class interval.