A coupled phase diagram experiment and thermodynamic modeling of the MgO-MnO-Mn2O3-Ti2O3-TiO2 system at 1 bar total pressure is presented. High temperature equilibration and quenching experiments followed by the phase analysis using electron probe microanalysis and X-ray diffraction were performed to obtain complex phase equilibria between solid solutions and liquid phase in air. Low temperature phases during quenching was inevitable in some samples which lead to inaccuracy in the experimental data. The molten oxide phase was described by using the Modified Quasichemical Model, which considers short-range ordering in liquid state, and the Gibbs energies of the extensive solid solutions (pseudobrookite, ilmenite and spinel) were described using the Compound Energy Formalism based on their crystal structures. A set of optimized model parameters of all phases was obtained, which reproduces all the reliable experimental data within experimental error limits from 25 °C to above the liquidus temperatures over the entire range of composition at air atmosphere. The model can also predict the phase equilibria in the range of oxygen partial pressures from metallic saturation to air. The complex phase relationships in the system have been elucidated for the first time and the database of the model parameters can be used with FactSage software to calculate any phase diagrams and thermodynamic properties of the MgO-MnO-Mn2O3-Ti2O3-TiO2 system.

中文翻译：

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MgO-MnO-Mn2O3-Ti2O3-TiO2体系的耦合实验研究和热力学模拟

介绍了 1 bar 总压力下 MgO-MnO-Mn2O3-Ti2O3-TiO2 系统的耦合相图实验和热力学模型。进行高温平衡和淬火实验，然后使用电子探针微量分析和 X 射线衍射进行相分析，以获得空气中固溶体和液相之间的复杂相平衡。在某些样品中，淬火过程中的低温阶段是不可避免的，导致实验数据不准确。熔融氧化物相采用修正准化学模型描述，该模型考虑液态短程有序，广泛固溶体（伪板钛矿、钛铁矿和尖晶石）的吉布斯能量采用基于其晶体的复合能量形式描述结构。获得了一组所有相的优化模型参数，它再现了在空气气氛下整个组成范围内从 25°C 到高于液相线温度的实验误差范围内的所有可靠实验数据。该模型还可以预测从金属饱和到空气的氧分压范围内的相平衡。首次阐明了系统中复杂的相关系，模型参数数据库可以与 FactSage 软件一起使用，计算 MgO-MnO-Mn2O3-Ti2O3-TiO2 系统的任何相图和热力学性质。该模型还可以预测从金属饱和到空气的氧分压范围内的相平衡。首次阐明了系统中复杂的相关系，模型参数数据库可以与 FactSage 软件一起使用，计算 MgO-MnO-Mn2O3-Ti2O3-TiO2 系统的任何相图和热力学性质。该模型还可以预测从金属饱和到空气的氧分压范围内的相平衡。首次阐明了系统中复杂的相关系，模型参数数据库可以与 FactSage 软件一起使用，计算 MgO-MnO-Mn2O3-Ti2O3-TiO2 系统的任何相图和热力学性质。