Near-dry electrical discharge machining of stainless steel

Abstract

Near-dry electrical discharge machining (NDEDM) has characteristics of high material removal rate (MRR) and low tool wear rate (TWR). NDEDM uses the mixture of air and water as a two-phase dielectric fluid, so it does not produce toxic fumes like conventional EDM which uses hydrocarbon-based oils as the dielectric fluid. Realising all these advantages of NDEDM, it was selected to machine stainless steel. The effect of pulse current (IP), pulse-on time (Ton) and lift setting on NDEDM of stainless steel was investigated. Taguchi's technique was applied to obtain an optimal setting of the process parameters. 'The higher the better' approach was used for MRR as higher MRR is desired. The measured results and subsequent analysis revealed that IP was the only significant parameter. MRR increases with an increase in IP. Also, TWR was found to be negligible in comparison of MRR. © 2015 Inderscience Enterprises Ltd.