Experiment investigation of using wire electrochemical machining in deionized water to reduce the wire electrical discharge machining surface roughness

Abstract

When the workpiece is sliced by using wire electrical discharge machining (WEDM), the materials are removed by melting and evaporation. Owing to the material removal mechanism, the surface of the workpiece after WEDM is composed of recast layer and numerous discharge craters, leading to the low surface roughness. In this study, wire electrochemical machining (WECM) is introduced to eliminate the recast layer and improve the surface quality of the workpiece cut by using WEDM. Two methods, which are based on electrochemical dissolution reactions, are proposed to dissolve the recast layer and craters on the WEDM surface. The processes are conducted on the same machine tool with the same electrolyte (deionized water) and the same machining parameters. Two factors, which have a great influence on the surface roughness, namely the feed rate of the wire electrode and the movement distance of the workpiece, are analyzed. Experiment results show that the recast layer and craters on the WEDM surface can be dissolved owing to the anodic dissolution of WECM, and the surface quality can be improved. In order to obtain the good surface roughness, the wire electrode should be fed as slow as possible during the electrolysis, and the movement distance of the workpiece should be appropriate.