In-situ synthesis and reaction mechanism of β-SiAlON in the Al-Si3N4-Al2O3 composite material

An Al-Si3N4-Al2O3 composite material has been successfully prepared by sintering at 1300 °C under nitrogen atmosphere, and X-ray diffraction, scanning electronic microscopy, and electronic differential system were used for its characterization. β-SiAlON with Z=1 (Si5AlON7) appears in the as-synthesized composite material as a reinforcing phase leading to an improvement of the overall physical properties of the Al-Si3N4-Al2O3 composite. The thermal dynamic analysis of the reaction indicates that Al reacts to Al4C3 and Al4O4C. Our thermal dynamic analysis reveals that the addition of Si3N4 to Al4O4C leads to the formation of β-SiAlON.