Equilibrium Relationships between Oxide Compounds in MgO-Ti2O3-Al2O3 with Iron at 1 873 K and Variations in Stable Oxides with Temperature

It is important to determine the equilibrium relationships between the oxide compounds in MgO-Ti2O3 Al2O3 and iron to avoid Al2O3 or MgO-Al2O3 formation and for inclusion control. In this study, the equilibrium relationships between the oxide compounds in MgO-Ti2O3-Al2O3 and molten iron are investigated at 1 873 K. The phase-stability diagrams, which show the equilibrium relationships between the oxide compounds in MgO-Ti2O3-Al2O3 and molten iron, are described. It is also important to know the oxides that newly form after solidification. Accordingly, the temperature-dependences of the stable compounds that newly form after solidification were investigated using the thermodynamic calculation software Fact Sage 6.1. Although the compounds formed after solidification are not necessarily the same as the equilibrium oxide compounds at 1 873 K, the correlation between them can be confirmed. In particular, under the unstable condition of MgAl2O4 at 1 873 K, it is found that the formation of MgAl2O4 could also be suppressed after solidification.