Grain growth in sol-gel derived alumina-zirconia composites

Grain-growth kinetics in sol-gel derived alumina-zirconia composites, containing 20 wt% ZrO2 stabilized with 0, 3 and 6 mol% ceria have been examined. The growth of alumina grains was effectively retarded by zirconia particles and a lake of abnormal growth was evident. Coupled grain growth was observed, but only if the required minimal sintering conditions (i.e. minimal sintering density) were reached. Measured grain-growth exponents indicate that the grain-boundary diffusion-controlled growth is probably the dominant rate-controlling mechanism in this system. (C) 1998 Chapman & Hall.