Abstract
Effects of SiC and ZrO2 dispersions on the microstructure, fracture toughness and strength were investigated for Al2O3-SiC-ZrO2 composites. The Al2O3-SiC-ZrO2 composites were prepared by hot-pressing the mixtures of fine Al2O3, SiC and ZrO2 powders. Transmission electron microscopic observation indicated that finer ZrO2 particles were dispersed mainly, within Al2O3 grain whereas large ZrO2 grains were located at the grain boundary of Al2O3 and most of SiC particles were dispersed within Al2O3 grains and large ZrO2 grains. The fracture toughness and strength of this composites were greatly enhanced by incorporating the ZrO2 and SiC particles into Al2O3. The toughening and strengthening mechanisms of Al2O3-SiC-ZrO2 composites were discussed.
