The Al-P system and Fe-Al-P system have been thermodynamically optimized using the CALculation of PHAse Diagrams (CALPHAD) method based on critical evaluation of all available experimental data. The liquid phases and solid solutions were modeled using the Modified Quasichemical Model and Compound Energy Formalism, respectively. The Gibbs energies of stoichiometric AlP compound and liquid Al-P solution were critically optimized to reproduce the melting point of AlP and the liquidus of Al-P system on the Al-rich corner. In the ternary Fe-Al-P system, the behavior of P in the liquid was also well optimized with introduction of Toop interpolation technique (Al as an asymmetric component). In addition, various phase equilibria of Fe-Al-P alloys containing up to 30 wt.%Al and 15 wt.%P, isothermal sections at 450, 650 and 800 °C, and the solubility of P in BCC_A2 Fe-Al alloys were excellently described, compared to experimental data. According to the present optimization, an accurate and consistent thermodynamic database of the Fe-Al-P system has been developed.

中文翻译：

---

Al-P 和 Fe-Al-P 系统的关键评估和热力学优化

Al-P 系统和 Fe-Al-P 系统已使用 PHA 酶图计算 (CALPHAD) 方法基于对所有可用实验数据的关键评估进行热力学优化。液相和固溶体分别使用修正的准化学模型和复合能量形式化建模。化学计量的 AlP 化合物和液态 Al-P 溶液的吉布斯能量经过严格优化，以再现 AlP 的熔点和富铝角上 Al-P 系统的液相线。在三元 Fe-Al-P 体系中，通过引入 Toop 插值技术（Al 作为非对称成分），P 在液体中的行为也得到了很好的优化。此外，含有高达 30 wt.%Al 和 15 wt.%P 的 Fe-Al-P 合金的各种相平衡，450、650 和 800 °C 的等温截面，与实验数据相比，P 在 BCC_A2 Fe-Al 合金中的溶解度得到了很好的描述。根据目前的优化，已开发出准确且一致的 Fe-Al-P 系统热力学数据库。