Dry and Near-Dry Electrical Discharge Machining

Abstract

This chapter aims to working mechanisms, influencing parameters, and the advantages and disadvantages of dry and near-dry Electrical Discharge Machining (EDM). Conventional die-sinking EDM, though it offers many advantages, is not environmentally friendly. It produces harmful gases and waste. Researchers, therefore, have come up with many solutions for this issue, one of the prominent ones among them being the use of a gaseous dielectric or a liquid mixed gaseous dielectric. Dry electrical discharge machining uses a gaseous dielectric in the place of the liquid dielectric used by conventional wet EDM. The high-velocity gas flow aids in the molten material removal. However, the molten material flushing is not as effective as that in wet EDM due to the gaseous medium being less dense. The feasibility of EDM with liquid-gas mixtures was first investigated by Tanimura et al. The parametric study of dry and near-dry EDM is essential to understanding the influence of different operating parameters on machining performance.