Abstract
Al2O3/SiC nanocomposites exhibited the high fracture toughness and strength at room temperature and good high-temperature mechanical properties. These significant improvements of mechanical properties were contributed to the dispersion of nanometer-size SiC particle within Al2O3 matrix grains. In this paper, the sinterability of Al2O3/SiC nanocomposites containing 5vol%SiC particles was compared to the sinterability of monolithic Al2O3. Especially, the densification and grain growth behaviors of Al2O3 with nanometer-size SiC particles were investigated in a temperature range of 1000° to 1800°C during hot-pressing to clarify the role of nanometer-size SiC particle for Al2O3/5vol% SiC nanocomposites. The addition of SiC particle remarkably delayed the densification rate and grain growth of Al2O3 matrix grain. In addition, TEM observation showed that SiC particles were dispersed within Al2O3 matrix grains for Al2O3/SiC nanocomposite hot-pressed above 1200°C. The consolidation process will be discussed in detail for these Al2O3/SiC nanocomposites.
