Development and Performance Analysis of Copper–Graphene Composite Electrodes for Electrical Discharge Machining Applications

Electrical Discharge Machining (EDM) is an advanced process used for machining electrically conductive materials that are difficult to machine using conventional techniques. Copper is widely employed as an EDM tool material due to its excellent electrical conductivity and heat transfer properties. Still, its application is limited by a high tool wear rate when machining hard conductive materials. To overcome this limitation, the present study investigates copper reinforced with graphene (Gr) to develop advanced EDM electrodes. Copper–graphene (Cu–Gr) composites with varying graphene contents were fabricated using powder metallurgy and utilized as EDM electrodes for machining IS2062 steel, with performance evaluated in terms of material removal rate (MRR), tool wear rate (TWR), and surface roughness (SR). Surface characterization of the tool and workpiece was carried out using Scanning Electron Microscopy and Energy Dispersive X-ray Analysis (SEM–EDX). The findings revealed that lower graphene content in the copper matrix enhanced MRR, reduced TWR, and improved surface finish compared to higher graphene concentrations. Specifically, the Cu–0.4 weight% Gr composite electrode achieved 21% and 44% higher MRR, 8% and 56% lower TWR, and 24% and 43% lower SR compared to the Cu–0.8 weight% Gr and Cu–1.2 weight% Gr electrodes, respectively. Overall, the Cu–0.4 weight% Gr composite also outperformed pure copper electrodes, showing an 18% improvement in MRR and a 35% reduction in SR, with only a 6% increase in TWR.