Assessment of thermodynamic functions in the MgO–Al2O3–SiO2 system

Abstract The Kapoor-Frohberg cell model and two-sublattice ionic liquid model were used to describe liquid phase in the system MgO–Al 2 O 3 –SiO 2 . Solid solution phases were described by the compound energy formalism. Two data sets have been created based on the same description of solid phases and different models of liquid. It is shown that both models of liquid reproduce experimental data in binary systems very well. Thermodynamic parameters of ternary compounds cordierite and sapphirine were assessed from subsolidus reactions. The liquidus surface for the MgO–Al 2 O 3 –SiO 2 system is calculated for both models of liquid. The comparison of calculated phase diagrams with experimental data shows that the Kapoor-Frohberg cell model reproduces experimental data better than the ionic sublattice model.