Phase equilibria and structural transformations in the ternary ZrO2–CeO2–Yb2O3 system at 1100°C were studied by X-ray diffraction over the entire composition range. Fields of solid solutions based on monoclinic (M) and tetragonal (T) ZrO2 modifications, cubic (C) Yb2O3 modification, cubic fluorite-type (F) CeO2 (ZrO2) modification, and an intermediate Zr3Yb4O12 (δ) orthorhombic phase were found to exist in the system. The boundaries of the phase fields and lattice parameters of the phases were determined. The maximum solubility of cerium oxide in the δ phase was 4 mol.% at the CeO2–(60 mol.% ZrO2–40 mol.% Yb2O3) section. Solid solutions based on the tetragonal ZrO2 modification were established to form in the region with high ZrO2 content. The solubility of Yb2O3 in T-ZrO2 is low and comes to δ0.5 mol.%, which is evidenced by X-ray diffraction and microstructural analyses. The solid solutions based on the tetragonal ZrO2 modification cannot be quenched from high temperatures in the chosen cooling conditions. An infinite series of F-CeO2(ZrO2) solid solutions forms at 1100°C. The isothermal section of the ZrO2–CeO2–Yb2O3 system at 1100°C contains one three-phase region (F + C + δ), five single-phase regions (FCeO2(ZrO2), M-ZrO2, T-ZrO2, δ, C-Yb2O3), and five two-phase regions (C + F, C + δ, F + δ, F + T, T + M). New phases were not found in the system. The nature of phase equilibria in the ternary ZrO2–CeO2–Yb2O3 system at 1100°C is determined by the constitution of binary phase diagrams.

中文翻译：

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ZrO2-CeO2-Yb2O3 体系中 1100°C 的相平衡

通过 X 射线衍射在整个组成范围内研究了 1100°C 下 ZrO2-CeO2-Yb2O3 三元体系中的相平衡和结构转变。发现基于单斜 (M) 和四方 (T) ZrO2 改性、立方 (C) Yb2O3 改性、立方萤石型 (F) CeO2 (ZrO2) 改性和中间 Zr3Yb4O12 (δ) 正交相的固溶体场系统中存在。确定了相场的边界和相的晶格参数。在 CeO2–(60 mol.% ZrO2–40 mol.% Yb2O3) 部分，氧化铈在 δ 相中的最大溶解度为 4 mol.%。建立基于四方 ZrO2 改性的固溶体，以在 ZrO2 含量高的区域形成。Yb2O3 在 T-ZrO2 中的溶解度很低，达到 δ0.5 mol.%，X 射线衍射和显微结构分析证明了这一点。在选定的冷却条件下，基于四方 ZrO2 改性的固溶体不能从高温淬火。在 1100°C 形成无限系列的 F-CeO2(ZrO2) 固溶体。ZrO2–CeO2–Yb2O3 系统在 1100°C 的等温截面包含一个三相区 (F + C + δ)、五个单相区 (FCeO2(ZrO2)、M-ZrO2、T-ZrO2、δ、 C-Yb2O3）和五个两相区（C+F、C+δ、F+δ、F+T、T+M）。系统中未发现新相。三元 ZrO2-CeO2-Yb2O3 系统在 1100°C 时相平衡的性质由二元相图的构成决定。在 1100°C 形成无限系列的 F-CeO2(ZrO2) 固溶体。ZrO2–CeO2–Yb2O3 系统在 1100°C 的等温截面包含一个三相区 (F + C + δ)、五个单相区 (FCeO2(ZrO2)、M-ZrO2、T-ZrO2、δ、 C-Yb2O3）和五个两相区（C+F、C+δ、F+δ、F+T、T+M）。系统中未发现新相。三元 ZrO2-CeO2-Yb2O3 系统在 1100°C 时相平衡的性质由二元相图的构成决定。在 1100°C 形成无限系列的 F-CeO2(ZrO2) 固溶体。ZrO2–CeO2–Yb2O3 系统在 1100°C 的等温截面包含一个三相区 (F + C + δ)、五个单相区 (FCeO2(ZrO2)、M-ZrO2、T-ZrO2、δ、 C-Yb2O3）和五个两相区（C+F、C+δ、F+δ、F+T、T+M）。系统中未发现新相。三元 ZrO2-CeO2-Yb2O3 系统在 1100°C 时相平衡的性质由二元相图的构成决定。