Abstract
The fusibilities and liquidus temperatures of 10 compositions of the K2ZrF6–K2NbF7–KF–KCl quaternary system are determined in the component concentration ranges (mol %) 1.73–4.03 K2ZrF6, 2.33–4.55 K2NbF7, 48.62–65.37 KF, and 30.57–42.83 KCl. The studies are performed by differential thermal analysis on cooling. The dependence of the liquidus temperature on the molar ratios of the fluoride components of the molten phase is revealed. The compositions characterized by low molar ratios of potassium fluorozirconate to potassium fluoroniobate and simultaneously high molar ratios of potassium fluoride to the sum of zirconium and niobium salts have the lowest melting points. These ratios are 0.52–0.56 and 10.5–13.7, respectively. The liquidus temperatures of these compositions are in the range 854–873 K. High melting temperatures are characteristic of the melts that have the highest molar ratios of potassium fluorozirconate to potassium fluoroniobate and low molar ratios of potassium fluoride to the sum of the moles of zirconium and niobium salts. These ratios are 5.4–7.9 and 0.8–1.1, respectively. The liquidus temperatures of these compositions are 920–974 K.
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Trifonov, K.I., Krotov, V.E., Nikiforov, A.F. et al. Fusibility of the K2ZrF6–K2NbF7–KF–KCl System. Russ. Metall. 2022, 955–957 (2022). https://doi.org/10.1134/S0036029522080225
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DOI: https://doi.org/10.1134/S0036029522080225