Thermodynamic Assessment of the Miscibility Gaps and the Metastable Liquidi in the B2O3–RO Systems (R = Mg, Ca, Sr, and Ba)

In an attempt to understand the liquid–liquid phase separation in the B₂O₃–MgO, B₂O₃–CaO, B₂O₃–SrO, and B₂O₃–BaO systems, the liquid miscibility gaps were calculated using the optimized interaction parameters of liquid phases. The Gibbs energies of liquid phases were derived in the form of a subregular solution from an optimization procedure based on phase diagram data. In addition, metastable liquidus boundaries and spinodal curves were also assessed by using the Gibbs energies of liquid phases. The present results were compared and discussed with other experimental and assessed data available in the literature.