Research on Mechanism of Ultra-Precision Electrical Discharge and Mechanical Grinding for Nonconductive Engineering Ceramics

A new method known as electrical discharge and grinding with synchronous servo double electrodes (EDGSSDE) is presented in this paper for nonconductive engineering ceramics which integrates electrical discharge and mechanical grinding with a metal bonded diamond conductive wheel. Also the mechanism of this method is analyzed. The results show that electrical discharge and electrolysis occur simultaneously during the process, which makes the diamond grains always in knife-edge, and achieves in-process dressing of grinding wheel. Due to the effects of high temperature and high heat generated by electrical discharge, a metamorphosed layer is formed on the surface of ceramics, which debases the rigidity of workpiece. The conductive grinding wheel grinds the metamorphosed layer and achieves paucity of ceramics removal by minute fritter. This method can dress grinding wheel in-process, avoid micro-crack that produced in traditional engineering grinding, reduce the grinding force, improve the service life of grinding wheel, advance the surface quality and machine nonconductive engineering ceramics in ultra-precision.