Multi-objective Optimization of PMEDM of Cylindrical Parts with Graphite Electrodes

The present work presents an experimental work to find optimal process factors for processing cylindrical parts by graphite electrodes in powder-mixed electrical discharge machining (PMEDM). This is a multi-criteria task with two criteria counting maximal material removal speed (MRS) and minimal surface roughness (RS) with the machining material being 90CrSi tool steel. Besides, the Minitab R19 and the Taguchi design were applied for designing the experimental matrix and evaluating experimental outcomes. Additionally, the servo current IP (A), the servo voltage SV (V), the powder concentration Cp (g/l), the pulse on time Ton (µs), and the pulse off time Toff (µs) were chosen as the input factors. The influence of the input factors on the multi-criteria target was given. As well, optimal process factors to ensure simultaneous single objective functions mentioned above were given.