Study of Fine-Finish Wire EDM

Abstract

In this paper, methods of obtaining fine-finish surfaces in wire electrical discharge machining are discussed. Some countermeasures to reduce the stray capacitance of wire EDM, which restricts the surface roughness on an EDMed surface, are described. A surface roughness of 0.6[μm] Rz is obtained using a 0.1[μs] pulse width group type AC pulse generator. However, we observed a problem of streaking on the machined surface. To determine the causes of such streaking, the wire behavior during the machining is observed. The mechanism of fine finish wire EDM and the reason of the streaking are discussed.