A Study of Material Removal during Electrical-Discharge Drilling of Hybrid Metal Matrix Composites

Abstract

In this paper, the machinability behavior of hybrid metal matrix composites (HMMCs) has been experimentally investigated. The experiments were performed at different level of (i) discharge current, (ii) pulse-on-time, (iii) pulse-off-time, and (iv) tool rotational speed. The intrinsic influence of these parameters on the material removal rate (MRR) has been investigated during electrical-discharge drilling (EDD) of developed HMMCs using copper electrode and quenched copper electrode. The influence of powder-mixed dielectric on MRR has also been investigated. The results of the experimental investigation indicated that the MRR is increased with discharge current (6 to 30 A) and pulse-on-time (60 to 500 µs) and decreased with pulse-off-time (8 to 90 µs) and tool rotational speed (400 to 1200 RPM).