Fabrication and microstructure of Al2O3-SiC-YAG hybrid composites prepared by particulate dispersion

Stable Al2O3-SiC-YAG hybrid composites were successfully fabricated by reaction of Al2O3 and Y2O3 and incorporation of SiC. The hot-pressed bodies consisted of uniformly dispersed grains of microsized YAG particulates and nanosized SiC particulates in an Al2O3 matrix. Although the grain size of monolithic Al2O3 increases markedly with increased temperature, the grain size of the Al2O3-SiC-YAG hybrid composites was effectively restrained due to grain-boundary pinning by the particulates.