Electrical Discharge Machining and Grinding of SiC Single Crystal Using a Disc-type Hybrid Tool of Polycrystalline Diamond

Abstract

Silicon carbide (SiC) single crystal was machined using a disc-type hybrid tool of polycrystalline diamond (PCD). The tool can be used to perform electrical discharge machining (EDM) as a roughing process and grinding as a finishing process. The width of the discharge gap and the thickness of the resolidified layer caused by EDM were measured, the results of which were then used to optimize the subsequent grinding conditions. As a result, ductile mode grinding was realized by removing the EDM-induced resolidified layer completely. In addition, a low surface roughness was obtained after grinding by utilizing the electrical discharges in EDM to dress the PCD tool surface. Finally, high surface integrity and productivity were successfully sustained by optimizing the EDMgrinding cycles.