Nitride Capacity of the Molten CaO-SiO2-Al2O3 System Containing TiO2 or ZrO2 and Equilibrated with Molten Si
Minoru SASABE, Satoshi YAMASHITA, Sumio SHIOMI, Tsuyoshi TAMURA, Hiroto HOSOKAWA, Ken-ichi SANO
Nitride capacity of molten CaO-SiO2-Al2O3 containing TiO2 or ZrO2 was observed. The molten oxides were equilibrated with nitrogen gas of 1013 hPa and with metallic Si to controll acculately oxygen partial pressure in the oxide phase. The experimental procedure was developed by the authors.
It is estimated that oxygen partial pressure in the molten oxide phase was controlled by the following reaction equation.
CaO-SiO2-Al2O3 system: Si+ O2 = SiO2
CaO-SiO2-Al2O3-TiO2 system: TiO2+4Si+O2=TiSi2+2SiO2
CaO-SiO2-Al2O3-ZrO2 system: ZrO2+4Si+ O2=ZrSi2+2SiO2
The nitride capacities measured by the procedure are comparatively same as that reported by other investigators.