Surface Roughness in Abrasive Mixed Rotary Electrical Discharge Machining: Experimental Approach

This research study focused on the alliance of blending silicon carbide powder of size 60 μm into dielectric oil (kerosene) with electrode revolution in electrical discharge machining of D3 steel using electrode made of copper. Peak current, pulse on-time, and electrode revolution were picked as machining variables to check their influence on the surface roughness of the workpiece. The full factorial experimentation was performed with 27 experimental runs. The analysis of variance result indicated electrode revolution as the most influential variable with a percentage aid of 32.75%, followed by peak current and pulse on-time, which accounted for 28.98 and 6.09%, respectively. The decrement in surface roughness was recorded at higher electrode rotational speed. The field emission scanning electron microscopy of machined samples was performed and results showed significant improvement on surface characteristics. The surface finish improved from 12.36 μm to 10.32 μm in silicon carbide powder blended rotational electrical discharge machining over traditional electrical discharge machining. The minimum surface roughness achieved was 4.81 μm at optimal conditions.