Abstract The paper considers phase equilibria in the subsolidus region of the GdFeO3-SrFeO3-δ system in air. By using X-ray powder diffraction, SEM/EDS, and Mossbauer spectroscopy, a GdFeO3-SrFeO3-δ phase diagram was constructed in the 1300–1500 °C temperature range. The samples of Gd1-xSrxFeO3-α for this study were synthesized by solid-phase chemical reactions. The study of phase equilibria in the GdFeO3-SrFeO3-δ system showed the presence of three areas, that is, of solid solutions based on the strontium-poor GdFeO3 orthorhombic phase, of the strontium-rich SrFeO3-δ cubic phase, as well as of an intermediate region in the mixture of these phases. The miscibility gap width (Δx) decreases from 0.54 to 0.35 with an increase in temperature from 1300 to 1500 °C.

中文翻译：

---

空气中 GdFeO3-SrFeO3- 系统的亚固相平衡

摘要 本文考虑了空气中 GdFeO3-SrFeO3-δ 体系亚固相线区域的相平衡。通过使用 X 射线粉末衍射、SEM/EDS 和穆斯堡尔光谱，在 1300-1500 °C 温度范围内构建了 GdFeO3-SrFeO3-δ 相图。本研究中的 Gd1-xSrxFeO3-α 样品是通过固相化学反应合成的。GdFeO3-SrFeO3-δ 体系相平衡的研究表明存在三个区域，即基于贫锶 GdFeO3 正交相的固溶体、富锶 SrFeO3-δ 立方相以及在这些相的混合物中的中间区域。随着温度从 1300°C 升高到 1500°C，混溶间隙宽度 (Δx) 从 0.54 减小到 0.35。