Electro Discharge Machining of WC/Ni Mixed Ceramic

Proper selection of manufacturing conditions is one of the most important aspects in the die sinking Electrical Discharge Machining (EDM) process, as these conditions determine important characteristics such as Material Removal Rate and Surface Roughness.In this work, mathematical models have been developed for relating the Material Removal Rate (MRR) and Surface Roughness (Ra), to machining parameters like tool rotational speed (S), discharge current (C), pulse-on time (T) and flushing pressure (P). The experiment plan adopts the centered central composite design unblocked (CCD). The separable influence of individual machining parameters and the interaction between these parameters are also investigated by using analysis of variance (ANOVA). This study highlights that the proposed mathematical models have proven to fit and predict values of performance characteristics close to those readings recorded experimentally with a 95% confidence interval. Results show that are the two significant factors affecting MRR (discharge current and flushing pressure). The discharge current, flushing pressure and electrode rotation have statistical significance on the Ra.