Parametric Investigation and optimization of Near-Dry Electrical Discharge Machining

Abstract

This study investigates near-dry Electric Discharge Machining (EDM) in order to achieve higher Material Removal Rate (MRR), lower Tool Wear Rate (TWR) and Better surface finish than conventional EDM on High Speed Steel (HSS) workpiece. Taguchi L₂₇ orthogonal array was used for conducting experimentation. The experiments have been conducted by mixing of limited quantities of water with high pressure air (air-mist). This paper presents a relatively simple device to be used for applying the near-dry EDM. The near-dry EDM does not produce toxic fumes so called Environment friendly machining process for the applied operating conditions, the near-dry electrical discharge machining presents some advantages regarding the machined surface quality and the electrode tool wear, in comparison with the machining that uses liquid dielectric. The effect of different process parameters like applied current, duty factor, gap control, sensitivity, tool lift was analyzed on MRR, surface finish and tool wear rate.