A critical evaluation and thermodynamic modeling study including key phase diagram experiments was performed to investigate the K₂O-Al₂O₃ and K₂O-MgO-Al₂O₃ systems. For the first time, potassium β- and βʹʹ-alumina solid solutions were described using the Compound Energy Formalism with accurate cation distributions in their sublattices. From the new experimental results, the stability of potassium βʹʹ-alumina was assured up to 1600 °C. A large discrepancy reported in the literature, the eutectic temperature between KAlO₂ and β-alumina in the K₂O-Al₂O₃ system, was resolved. A set of self-consistent Gibbs energy functions for all stable phases in the K₂O-MgO-Al₂O₃ system was obtained. As a result, any phase diagram sections and thermodynamic properties of the K₂O-MgO-Al₂O₃ system can be calculated from the optimized Gibbs energy functions. In particular, the cation distribution in the β- and βʹʹ-alumina solid solutions is calculated depending on the non-stoichiometry of solution and temperature.

进行了包括关键相图实验在内的关键评估和热力学建模研究，以研究K ₂ O-Al ₂ O ₃和K ₂ O-MgO-Al ₂ O ₃系统。首次使用复合能量形式主义描述了β-和βʹʹ-氧化铝钾固溶体在其亚晶格中具有准确的阳离子分布。根据新的实验结果，可以确保βʹʹ-氧化铝钾在高达1600°C的温度下具有稳定性。文献报道存在很大差异，即K ₂ O-Al ₂ O _3中的KAlO ₂和β-氧化铝之间的共晶温度系统，已解决。对于K ₂ O-MgO-Al ₂ O ₃系统中的所有稳定相，获得了一组自洽的吉布斯能量函数。结果，可以从优化的吉布斯能量函数计算出K ₂ O-MgO-Al ₂ O ₃系统的任何相图截面和热力学性质。特别地，根据溶液的非化学计量和温度来计算β-和β4-氧化铝固溶体中的阳离子分布。