ELID grinding characteristics and surface modifying effects of aluminum nitride (AlN) ceramics

Aluminum nitride (AlN) ceramics have excellent electrical insulation and dielectric properties, a high thermal conductivity that is approximately 10 times that of alumina, as well as a thermal expansion coefficient that is close to that of Si, and so are anticipated to be used in semiconductor mounting boards, heat-dispersing substrates for power modules, and other heat-sink materials in a variety of high-added-value applications. In this research, ELID grinding was performed on AIN, and evaluated the processing characteristics and the resulting surface properties. The results indicate that final finishing using a #30,000 wheel produced an extremely smooth ground surface roughness of 0.008 μm Ra. In addition, the ELID series demonstrated a surface hardness and sliding characteristics superior to those of the polished series. This appears to be attributable to the diffusion phenomenon of the oxygen element produced by the ELID grinding.