Microstructure and thermal properties of slowly cooled Sn–10% Ag and Sn–20% Ag alloys were experimentally investigated in this study. It was found that microstructure of the studied alloys is composed of large, plate-like grains of Ag₃Sn intermetallic phase in the Sn-rich eutectic matrix. Phase transition temperatures and corresponding heat effects were experimentally determined and compared with the results of thermodynamic and phase equilibria calculations using the CALPHAD (CALculation of PHAse Diagrams) method and optimized thermodynamic parameters from literature. The xenon flash method was employed for the measurements of thermal diffusivity and determination of thermal conductivity in the temperature range from 25 to 150 °C. The results show that the thermal diffusivity and thermal conductivity gradually decrease with increasing temperature. The determined values of thermal conductivities of the investigated alloys are very close to each other and only slightly higher than that of pure tin. The contributions of electrons and phonons to the thermal conductivity of the studied alloys at room temperature were determined using the Wiedemann-Franz law and the obtained values of the thermal and electrical conductivities. The percentage contributions of the phonon component to the thermal conductivity for Sn–10% Ag and Sn–20% Ag alloys at 25 °C were found to be 20.5% and 28.9%, respectively.

本研究通过实验研究了缓慢冷却的 Sn-10% Ag 和 Sn-20% Ag 合金的微观结构和热性能。结果表明，所研究合金的微观结构由大的、板状的 Ag ₃晶粒组成。Sn 富锡共晶基质中的 Sn 金属间相。通过实验确定相变温度和相应的热效应，并与使用 CALPHAD（PHA 酶图计算）方法和优化的文献中的热力学参数的热力学和相平衡计算结果进行比较。氙闪法用于在 25 至 150 °C 的温度范围内测量热扩散率和确定热导率。结果表明，随着温度的升高，热扩散率和热导率逐渐降低。所研究合金的热导率的确定值彼此非常接近，仅略高于纯锡的热导率。电子和声子对室温下所研究合金的热导率的贡献是使用 Wiedemann-Franz 定律和获得的热导率和电导率值确定的。发现声子成分对 Sn–10% Ag 和 Sn–20% Ag 合金在 25 °C 时的热导率的百分比贡献分别为 20.5% 和 28.9%。