Microstructure of nano SiC dispersed Al2O3–ZrO2 composites

Nano-sized SiC dispersed YSZ (3 mol% Y2O3–ZrO2)–Al2O3 composites were fabricated by hot-pressing of SiC/YSZ/Al2O3 mixture and it was investigated the dispersed effect of nano SiC particles on suppression of grain growth as a function of hot-pressing temperature in the range of 1000–1800 °C. The SiC particulates were dispersed within the alumina grains and at grain boundaries. SiC particles significantly inhibited grain growth of the Al2O3 matrix. Significant grain growth was observed above 1600 °C for pure alumina and above 1700 °C for the YSZ–Al2O3 composites. In contrast, significant grain growth of the alumina matrix in the SiC–YSZ–Al2O3 composites did not occur due to the disturbance of grain boundaries migration by immobile nano SiC.