Abstract
The phase diagrams of Al2-xYxO3-SiO2-Si3N4 system (x=0.75 and 1.06) at 1500°C were studied. Oxynitride glasses were prepared by quenching a liquid phase at 1500°C. The maximum concentration of N atoms in the glasses prepared by this method was in the range of 4.6-4.9 at%. The glass transition temperature, the softening temperature and the crystallization temperature of Al-Y-Si-O-N oxynitride glasses were measured as a function of composition and found to increase with increase in N concentration. The Vickers hardness of the glasses increased with increase in N concentration. Stability and oxidation of oxynitride glass in air at temperatures from 950°C to 1100°C and the solubility of Si3N4 into glass were also studied and discussed.
