ABSTRACT
Electrical discharge machining (EDM) is a precise machining technique where machining is done by a series of repetitive sparks between electrode and workpiece. EDM not only results in finishing of workpieces, but also the wearing of electrode also occurs in addition. Since the performance of electrodes is important in EDM, it is necessary to understand the complex wearing behaviour of electrodes obtained during machining. It was observed that the wear of electrode is affected by a number of factors. While it is difficult to avoid or control the factors affecting the electrode wear, it is more appropriate to control the machining factors used in EDM. In the present study, wear of copper electrode (tool wear ratio, TWR) was investigated during machining of AISI 1035 steel. Experiments were designed using a full factorial design (FFD) of experiments and undertaking three critical EDM factors i.e. current (I), spark on time (T on), and spark off time (T off). ANOVA (analysis of variance) is used to determine the significant EDM factors affecting the wear of electrode and its performance. The impact of individual factors on TWR is demonstrated using main effect plot, and to minimize the wearing of electrode, the optimal setting of EDM factors that produces the minimum electrode wear is proposed using the desirability function approach.
