Influence of different tool electrodes on machining of oil hardened non shrinking steel using die sink electric discharge machine

Abstract

Tool steel has been a crucial material for many industrial applications and manufacturing of machining tools and milling cutters although very few machining techniques are available for machining of these materials. In this study, the performance of copper and brass tool electrodes on the die sink electric discharge machining of oil-hardened non shrinking steel (OHNS) has been evaluated. Current, pulse on time, and pulse off time were considered as the factors and the responses as material removal rate (MRR) and tool wear rate (TWR). The design of experiments technique namely the Box-Behnken design (BBD) under response surface methodology (RSM) was utilized. The response models were developed for MRR and TWR for brass and copper tool electrodes. The MRR and TWR for brass and copper tool electrodes were compared and represented graphically. The results show that current is the significant factor affecting both MRR and TWR and compared to brass, copper is a suitable electrode for die sink electric discharge machining of OHNS. The confirmative tests validate the developed response models of MRR and TWR.