Electrical Discharged Coating by Spark Plasma Sintered Tungsten Porous Electrode

This paper describes a high-hardness coating process by spark plasma sintered tungsten porous electrode with an electrical discharge machine utilizing the electrical discharge machining phenomenon. The effects of the electrical discharge machining conditions, the relative density of the sintered material used as the tool electrode, and the particle size on the coating properties were investigated. By using porous tungsten as the tool electrode, a processed surface with a higher hardness was achieved. In addition, the lower the relative density, the higher was the Vickers hardness of the processed surface. Spark plasma sintering (SPS) sintered tungsten was used, and it was observed that the larger the discharge current, and the larger the powder particle size of the SPS sintered tungsten was, the higher was the Vickers hardness of the processed surface.