Material removal rate and electrode wear study on the EDM of silicon carbide

In this work, a material removal rate (MRR) and electrode wear (EW) study on the die-sinking electrical discharge machining (EDM) of siliconised or reaction-bonded silicon carbide (SiSiC) has been carried out. The selection of the above-mentioned conductive ceramic was made taking into account its wide range of applications in the industrial field: high-temperature gas turbines, bearings, seals and lining of industrial furnaces. This study was made only for the finish stages and has been carried out on the influence of five design factors: intensity supplied by the generator of the EDM machine (I), pulse time (ti), duty cycle (η), open-circuit voltage (U) and dielectric flushing pressure (P), over the two previously mentioned response variables. This has been done by means of the technique of design of experiments (DOE), which allows us to carry out the above-mentioned analysis performing a relatively small number of experiments. In this case, a 25−1 fractional factorial design, whose resolution is V, has been selected considering the number of factors considered in the present study. The resolution of this fractional design allows us to estimate all the main effects, two-factor interactions and pure quadratic effects of the five design factors selected to perform this study.