Influence of conductive powders on surface characteristics in EDM: an experimental study using desirability optimization

Abstract The advancement of modern engineering materials with superior mechanical properties such as hardness, toughness, and brittleness presents significant challenges to conventional machining techniques, often leading to tool failure and poor surface finish. To address these limitations, non-conventional machining method; Electrical Discharge Machining (EDM) has developed. The efficiency of EDM is primarily governed by electrical parameters such as current, gap voltage, and the conductivity of electrodes and dielectric fluids. The conductive powder viz. silicon carbide and aluminium powder mixed in dielectric medium is to improve the surface roughness (SR). The incorporation of conductive powders into the dielectric fluid has shown promise in enhancing EDM performance by stabilizing spark generation, thereby improving surface finish. In this study desirability approach method is used to optimize and identify the best SR value. Moreover, the surface characteristics analysed by measuring recast layer thickness, microhardness. The use of aluminium powder showed the better surface finish than silicon carbide.