GRINDING OF SOL-GEL DERIVED ALUMINA-ZIRCONIA COMPOSITES

Alumina-zirconia powders containing 12 . 5 wt% zirconia were prepared by sol-gel processing. After calcination these powders were cold pressed, sintered and HIPed. The maximum amount of tetragonal form of zirconia is retained in these specimens. Grindability and the transformation behaviour of tetragonal zirconia were evaluated by conducting grinding studies at different speeds and depths of cut. The surface characteristics of the specimens and phase analysis of the specimens and grinding chips were determined. The surface finish improved as the grinding speed increased and with the decrease of depth of grinding. The grinding condition to obtain maximum amounts of tetragonal zirconia was optimized.