Effect of Carbothermal Reduction Nitriding of Si/SiO2 Composite Green on Properties of Fused Silica Ceramics

Si/SiO2 composite green body with solid content of 50% was prepared by low toxic gel system and sintered in nitrogen at high temperature. Nitrogen compounds were synthesized in situ on fused silica ceramic substrate. The influence of different temperatures on nitriding reaction was discussed: different temperatures were used for nitriding at 1350 °C, 1400 °C, 1450 °C, 1500 °C. The effect of different nitriding times on nitriding reaction was discussed: different holding times were used for nitriding +1 h, 1.5 h, 2 h and 2.5 h. The best nitriding process was obtained by analyzing the composition, microstructure and properties of the nitrided samples.