Comparative Evaluation of Flat and Convex Copper-Nanographene Electrodes in EDM: Effects on Performance Measures

Electrical Discharge machining (EDM) is a nontraditional technology, adopted for machining hard materials and geometrically complex parts that cannot be obtained via traditional manufacturing operations. Due to the tool wear rate (TWR), material removal rate (MRR), and surface roughness (SR) usually impacting EDM performance, it is important to conduct a novel study to reduce the (TWR), increase the (MRR), and improve surface quality. The present study aims to analyze the effect of different profiles of electrodes, such as flat and convex, and select the optimal electrode profile for making the holes for EDM performance enhancement. The electrodes were made of copper-nanographene material, 10 mm in diameter, for machining AISI 1005 carbon steel as the workpiece. The experiments were designed using Design-Expert 13 software. Three factors were selected: Peak current (Ip), pulse on time (Ton), and pulse off time (Toff). A comparative discussion is provided on the specificities of the machined surface achieved by utilizing the electrode tool. The study results revealed that the TWR of flat profile electrodes could be overcome by employing electrodes with convex profiles, which were observed to decrease by 17.37%. Also, electrodes with convex profiles produced an SR of better quality than flat profile electrodes, which decreased by 23.52%. The MRR for hole drilling was higher by 19.34% than that of the flat profile electrode.