Analysing the influence of EDM parameters and electrode type on H13 steel quality using response surface methodology

چکیده مقاله

The present work characterises the effect of electrical discharge machining (EDM) parameters and electrode type on the quality of H13 steel, with a comparison among copper, graphite and graphene-coated copper electrodes. Through a Response Surface Methodology (RSM) framework, the research quantifies the influence of voltage, electric current, spark on/off time and electrode material on critical outputs of the metal removal rate (MRR), tool wear rate (TWR) and surface roughness (SR). Microstructural evaluation via optical and scanning electron microscopes provides further insight into the surface integrity of the machined components. The results indicated that the optimal values of process parameters for simultaneous optimisation of MRR, TWR and SR include electric current of 7 A, voltage of 60 V, spark on time of 50 µs and spark off time of 100 µs. Also, under optimal parameter conditions, the highest MRR, lowest TWR and minimum SR were achieved by the graphite electrode. However, by coating the copper electrode with graphene nanoparticles, the MRR increased by 28.39% and the roughness of the sparked surfaces decreased by 68.85%.