PREPARATION OF FINE-GRAINED MONOCLINIC ZIRCONIA CERAMICS BY COLLOIDALPROCESSING

Fine-grained monoclinic zirconia ceramic was made from well-dispersed zirconia sol prepared by the hydrolysis of zirconium chloride oxide oc tahydrate. Dechlorinated and concentrated zirconia sol was consolidate d by pressure filtration. The relative green density of the compact wa s improved by the following cold isostatic pressing treatment at 400 M Pa. The compact was densified by pressureless sintering to > 98% of th eoretical density in air at 1100 degrees C, which is lower than that o f monoclinic to tetragonal transformation of pure zirconia. The averag e grain size of the sintered monoclinic zirconia ceramics was 92 nm.