Application of response surface methodology for evaluating material removal in rate die-sinking EDM roughing using copper electrode
Die-sinking electrical discharge machining (EDM) is one of the most popular machining methods to manufacture dies and press tools because of its capability to produce complicated shapes and machine very hard materials. In this article, MRR study on die-sinking EDM in rough machinng of SKD11 die steel has been carried out. Response surface methodology (RSM) has been used to plan and analyze the experiments. Current (I), pulse on time (Ton) and voltage (U) were chosen as process parameters to study the die-sinking EDM performance in term of MRR. The results indicated that in order to obtain a high value of MRR within the work interval of this study, Ton should be ﬁxed as low as possible, and conversely, the larger the selected I and U. And the optimal value of MRR was 139.126 mg/min at optimal process parameters I = 10 A, U = 90 V and Ton = 100 s. The mathematical model for the MRR can be effectively employed for the optimal process parameters selection in die-sinking EDM for SKD11 die steel. Empirical tests show that the model can calculate quite accurately predicted by MRR (error 0.6%).