Thermodynamic modeling of the Al–Si–Sr–O quaternary system

A thermodynamic description for the Al–Si–Sr–O quaternary system was developed in this study. Unlike previous publications which mostly focused on one particular pseudo-binary or pseudo-ternary section, the thermodynamic description developed in this study can be applied to the entire compositional range. For the six constituent binary systems, Al–O and Si–O were re-evaluated, while thermodynamic descriptions for the other four binaries were adopted from the published assessments. Thermodynamic descriptions for the Al–Si–O and Al–Sr–O ternaries were then obtained on the basis of the reevaluated Al–O and Si–O binaries. In addition, the Si–Sr–O ternary system was, for the first time, assessed in this study based on the literature experimental data. In the present study, associate model was used to describe the liquid phase and a four-sublattice compound energy model was used to describe the mullite (3Al2O3·2SiO2) phase. The developed thermodynamic description was validated by the experimental data available in the literature for this quaternary system.