Machining characteristics of titanium alloy (Ti–6Al–4V) using a combination process of EDM with USM

This paper presents an experimental investigation of the machining characteristics of titanium alloy (Ti–6Al–4V) using a combination process of electro-discharge machining (EDM) with ultrasonic machining (USM). The EDM and USM machining mechanisms were integrated to improve the machining efficiency and accuracy. During the experiments, parameters such as dielectric type, abrasive size, concentration of abrasive in the dielectric fluid, discharge peak current and pulse duration were changed to explore their effect on the material removal rate (MRR), electrode wear rate (EWR), relative electrode wear ratio (REWR), surface roughness and thickness of the recast layer. From the experimental results, we conclude that this combination EDM/USM process can increase the MRR and decrease the thickness of the recast layer. In addition, the discharge waveform analysis shows that the combination EDM/USM process can dramatically reduce abnormal discharge, thus improving the discharge efficiency.