Interfacial tension between a molten fluoride mixture and liquid bismuth

Interfacial tensions between the LiF-KF binary melt and liquid bismuth and between the LiF-BeF2 binary melt and liquid bismuth were measured over a wide range of salt composition by a modified maximum bubble pressure method. The experimental uncertainties were within 5%. Their interfacial tension isotherms show apparent negative deviation from the linear dependence on salt composition. It was found that the LiF-KF binary melt showed nearly ideal solution behavior in the interfacial tension as well as in the surface tension. On the other hand, the formation of the complex ion BeF42- would play an important role in the interfacial tension of the LiF-BeF2 binary melt-liquid bismuth system in the same way as in the surface tension. (author)