Exploring Drilling Control Variables for Enhanced Electric Discharge Machining Performance in Aluminum Hybrid Nanocomposite

A study optimized drilling control variables for electric discharge machining (EDM) of aluminum (Al) 6061 matrix alloy, reinforced with 0.6 wt.% silicon carbide (SiC) and 0.2 wt.% boron carbide (B₄C) hybrid nano metal matrix composite (MMC) using ultrasonic-aided stir casting. Examination of physical, mechanical, and microstructural parameters revealed that adding nanoparticles increased the density of Al 6061 alloy to 2.698 g/cm³. The Vicker's microhardness was 63.795 HV, 18% higher than the Al 6061 matrix alloy. The metallurgical inspection validated the uniform distribution of SiC and B₄C nanoparticles. Taguchi assessed the effects of pulse current, pulse on time, and gap voltage on surface roughness and overcut. Experimental studies of surface roughness show that pulse current (52.31%) is the drilling control variable with the highest impact. For overcut, pulse current is the primary drilling control variable at 66.02%. The hi-resolution scanning electron microscope (HRSEM) showed that pulse current increased crater size.