Enhancement of Electrochemical Discharge Machining (ECDM) Characteristics with Tool Electrode Rotation

Electrochemical discharge machining (ECDM) process is a novel process that utilizes the mechanism of thermal melting and chemical dissolution to machine the non-conductive materials. The occurrence of poor micro-hole machining characteristics in gravity-assisted tool feed is one of the challenges in ECDM process. The physical contact of the tool electrode with the work material results in ineffectual electrolyte availability, poor electrolyte flushing and non-uniform sparks. The present study attempts an experimental investigation for enhancing the micro-hole characteristics with the application of tool electrode rotational effect. Material removal rate (MRR), hole circularity (HC), radial overcut (ROC), and heat-affected zone (HAZ) are selected as a response characteristic. The microscopy images emphasized that tool electrode rotation substantially improved the machining characteristic of the micro-holes when compared to characteristic obtained without the tool rotation. Tool electrode rotation helps in replenishment of electrolyte flushing and enables better consistencies of spark distribution. It is concluded that the tool electrode rotation produces micro-holes with better hole circularity compared to stationary tools that produces poor hole circularity. Further, an improvement of 25.21% in MRR and 44.4% in ROC is obtained with the application of tool electrode rotation. The present study successfully describes the enhancement of ECDM characteristics with tool electrode rotation.