Prediction of Material Removal Rate in Die-sinking Electrical Discharge Machining

This paper proposes a semi-empirical model to predict material removal rate in die-sinking electrical discharging machining (EDM). Four different workpiece materials -- high strength steel, high strength low alloy steel, brass, and aluminum -- are utilized in the study. Full factorial experiments using peak current, on-time at two levels are selected for each workpiece material while keeping other parameters the same. The removed volumes are calculated by measuring sectional area of an EDM'ed hole and its dimensions. The developed MRR model includes the EDM cumulative electrical charge for each cycle and melting temperature of workpiece material; it predicts two orders of magnitude closer to experimental data compared to a published model that is based on melting temperature and peak current alone.