Effect of Various Dielectric Fluids on Performance of EDM: A Review

Abstract

In electrical discharge machining (EDM), material removal takes place by means of successive electrical discharges occurring between an electrode and a work piece in the presence of dielectric liquid or gas. As dielectric fluid plays very significant role in any electrical discharge machining operation, selection of dielectric medium is an important consideration for EDM performance. It does not only serve to carry away the condensed metal particles from the spark gap region but also has different functions which highly influence the performance of this process. An exhaustive research work had been carried out by different researchers for improvement of performance measures such as material removal rate (MRR), tool wear rate (TWR) and surface roughness of electrical discharge machining using different dielectric fluids like kerosene, deionized water, air, mineral oil, powder mixed dielectric, etc. In the powder mixed EDM process, a suitable material e.g. aluminium, nickel, iron, cobalt, copper, carbon or silicon carbide in the powder form is mixed into the dielectric fluid. This paper reviews the research work carried out to evaluate the effects of different dielectric fluid on performance measures of EDM.