SOME STUDIES IN ROTARY ECDM

Abstract

Electrochemical discharge machining (ECDM) is a well-known non-conventional manufacturing process used generally for machining of non-conductive materials like glass, ceramic, composites etc. This process has been tried with different variations worldwide in order to increase its efficiency and capability. The variation tried in this work consisted of circulating the electrolyte and rotating the tool alone or together. Glass being hard, brittle, non-reactive and smooth, bears great medical and industrial importance. The investigations were carried out on three types of glass namely, borosilicate, soda lime and optical glass using three different electrolytes; NaOH, NaCl and NaNO3. The features machined were micro channels of width approximately 900 jim and depth 500 jim. The effect of various input parameters like voltage, electrolyte concentration, tool rotational speed, inter electrode distance, tool feed and electrolyte stirring were investigated using Taguchi's design of experiment approach. The response variables considered were the material removal, tool wear and surface finish. The analysis of the developed micro channels showed that the response variables were strongly influenced by input parameters selected, with electrolyte having the maximum effect, followed by the applied voltage.