EDM with an Air-Assisted Multi-Hole Rotating Tool

Abstract

In the present research work, an extensive experimental study of air-assisted rotary electrical discharge machining (AAEDM) of high chromium, high carbon die steel has been made. Investigations have been performed to study the process factor effect namely pulse-on time, discharge current, duty cycle, tool rotation, and air pressure on material removal rate (MRR) and electrode wear ratio (EWR). A comparative analysis of solid rotary tool electrode electrical discharge machining (REDM) and AAEDM has been presented. It was found that a high MRR and low EWR occurred in AAEDM as compared to the REDM process, under the same processing conditions. Use of a multi-hole tool provided better circulation of dielectric in the discharge gap, thus it improved the flushing efficiency of the process. The results showed that the application of compressed air has a favorable influence on MRR and EWR.