Al₂O₃/SiCナノ複合材料の焼結挙動とナノ複合化プロセス

抄録

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.