Phase equilibria for the MnO-SiO2-Ti2O3 system

Abstract

Isothermal phase relations for the MnO-SiO2-Ti2O3 system were investigated at 1 773 and 1 573 K by a chemical equilibration technique. The solubility of Ti2O3 was found to be 30 to 40 mass% and 20 to 33 mass%, respectively. In the MnO-Ti2O3 binary system, the existence of 2MnO·TiOx was confirmed by X-ray diffraction. Isothermal phase relations for the MnO-SiO2-TiO2 system were also investigated at 1 773 K, as was the dependence of the SiO2-TiO2 doubly saturated composition in the MnO-SiO2-TiO2 system on temperature from 1 573 to 1 773 K. The dependence of Ti4+/Ti3+ ratio in 2MnO·TiOx on oxygen partial pressure (PO2=3.37×10-18 to 1.94×10-13atm) is discussed. © 1996 ISIJ.