Abstract The phase diagram of the KCl-Na2CO3 system was experimentally investigated for the complete range of compositions using differential scanning calorimetry (DSC). The results are in excellent agreement with the phase diagram that is computed by the two-sublattice models. Both DSC experimental curves and the Tammann diagram were used to determine the eutectic point and the results were compared. The latter provides more reliable and accurate information with the eutectic composition found to be 50.41 ± 0.78 wt%Na2CO3(41.67 ± 0.68 mol% Na2CO3). Physical properties at the eutectic point including solidification/melting temperature and latent heat of fusion/solidification were also studied. The results show a melting point of 581.76 ± 0.57 °C and latent heat of fusion of 260.40 ± 8.69 J/g. The occurrence of subcooling with a temperature difference of 5.58 ± 0.67 °C was also identified. The existence of a solid solution was confirmed in the current investigation using the Tammann diagram and Scanning Electron Microscopy/Energy Dispersive X-ray Spectroscopy (SEM-EDS).

中文翻译：

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二元KCl-Na2CO3体系的实验相图研究

摘要 使用差示扫描量热法 (DSC) 对 KCl-Na2CO3 系统的相图进行了全范围成分的实验研究。结果与由两个亚晶格模型计算的相图非常吻合。DSC实验曲线和Tammann图均用于确定共晶点并比较结果。后者提供了更可靠和准确的信息，发现共晶成分为 50.41 ± 0.78 wt% Na2CO3 (41.67 ± 0.68 mol% Na2CO3)。还研究了共晶点的物理特性，包括凝固/熔化温度和熔化/凝固潜热。结果显示熔点为 581.76 ± 0.57 °C，熔化潜热为 260.40 ± 8.69 J/g。还发现了温差为 5.58 ± 0.67 °C 的过冷现象。在目前的研究中，使用塔曼图和扫描电子显微镜/能量色散 X 射线光谱 (SEM-EDS) 证实了固溶体的存在。