Performance Measurement and Discharge Data Based Analysis of Ultrasonic Assisted μEDM for Ti6Al4V

Unconventional machining of difficult-to-cut conductive materials with high accuracy, low heat-affected zone formation, and the ability to cut intricate geometries entitles micro-electrical discharge machining (μEDM) as the most versatile technology in micromachining. Ultrasonic vibration assistance further enhances the material-removing ability of the μEDM process while imparting several other benefits. The present work proposes a comparative study between the unassisted and ultrasonic vibration assisted μEDM to the tool electrode for machining microslots on Ti6Al4V material using an in-house developed tool holder. The characteristics of the discharge waveforms were captured using a data acquisition system at high sampling rates. The pulse discrimination system is used to perform an in-depth study of the discharge pulses. μEDM milling experiments were performed to machine microslots at varying input voltages, capacitances, and feed rates. The ultrasonic vibrations proved beneficial in addressing the primary issue associated with the μEDM process, i.e., the material removal rate (MRR) with a maximum of 35% increment. Applying ultrasonic vibrations reduced the recast layer and tool wear rate (TWR) and increased the surface finish.