Abstract The phase equilibria of the Cu–Ag–Si system were investigated by a combination of key experiments and thermodynamic modeling. Eighteen ternary alloys were prepared to determine the isothermal sections at 500, 600, and 700 °C of the Cu–Ag–Si system by means of X-ray diffraction (XRD) and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDX). The solubilities of Ag in the Cu19Si6, Cu15Si4, Cu56Si11, and hcp(CuSi) phases were measured. No ternary compound was found in this isothermal sections. Based on the experimental equilibria data from the present work, thermodynamic assessment of the Cu–Ag–Si system was carried out by the CALPHAD (CALculation of PHAse Diagrams) approach. The solution phases (Cu), (Ag), (Si), and hcp(CuSi) were described using substitutional solution model and the binary phases Cu19Si6, Cu15Si4, and Cu56Si11 with the solubility of Ag were modeled by the sublattice models. A set of self-consistent thermodynamic parameters of the Cu–Ag–Si system was obtained. The isothermal sections at 500, 600, 650, and 700 °C, vertical sections at 10 and 20 at.% Ag, and liquidus projection were calculated. The reaction scheme of the Cu–Ag–Si system was constructed. The calculated results are in agreement with the experimental data from the present work and literature.

中文翻译：

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Cu-Ag-Si三元体系的实验研究和热力学建模

摘要 结合关键实验和热力学模型研究了 Cu-Ag-Si 系统的相平衡。制备了 18 种三元合金，通过 X 射线衍射 (XRD) 和具有能量色散 X 射线光谱 (SEM) 的扫描电子显微镜来确定 Cu-Ag-Si 体系在 500、600 和 700 °C 下的等温截面。 /EDX）。测量了 Ag 在 Cu19Si6、Cu15Si4、Cu56Si11 和 hcp(CuSi) 相中的溶解度。在该等温截面中未发现三元化合物。基于当前工作的实验平衡数据，通过 CALPHAD（PHAse 图计算）方法对 Cu-Ag-Si 系统进行了热力学评估。溶液相 (Cu)、(Ag)、(Si) 和 hcp(CuSi) 使用置换溶液模型和二元相 Cu19Si6、Cu15Si4、和具有 Ag 溶解度的 Cu56Si11 由亚晶格模型模拟。获得了一组自洽的 Cu-Ag-Si 系统热力学参数。计算了 500、600、650 和 700 °C 的等温截面、10 和 20 at.% Ag 的垂直截面以及液相线投影。构建了 Cu-Ag-Si 体系的反应方案。计算结果与现有工作和文献中的实验数据一致。