Study of Dry EDM with Helium-Oxygen Mixed Dielectric

Abstract

The electrical discharge machining (EDM) is a widely used unconventional machining because of its ability to cut very hard to machine material causing high dimensional accuracy as well. In this process material is removed by controlled erosion by spark generated in between tool electrode and work material in presence of dielectric medium which creates environmental issue.This Paper presents a comparative analysis of dry-EDM with two different gases as dielectric those are oxygen and helium to manufacture the hole on EN 31 carbon steel. The main aim is to study the effect of a discharge current, air pressure and flow of gas on Material removal Rate (MRR), Surface Roughness (Ra) and Tool Wear Rate (TWR). Influences of gas pressure, flow rate of the electrode are also discussed resulting in finding optimal conditions for machining, depending on the optimization criteria.