Development of Coat Wire Electrode for High-Performance WEDM (2nd Report): Fundamental WEDM Characteristics of φ50μm Coating Wire

The purpose of this study is to develop a new type of coating wire electrode. Piano wire with a very high tensile strength is coated with an electrically conductive layer in order to achieve high-speed and high-precision wire EDM. In our previous paper, using a wire of 200μm diameter, the fundamental effects of the thickness of brass and zinc layers on the machining characteristics were clarified. In this paper, using a trial-made thin wire of 50μm diameter, the optimum thickness and quality of the brass layer were experimentally investigated for the realization of higher-performance fine wire EDM. Furthermore, the effect of the tensile strength of the piano wire used as the core wire was discussed. As a result, a brass coating with a copper content of 60-70% is shown to be effective, and the thickness of the brass coating must be more than about 1.5μm to achieve a high removal rate.