Comparison of liquid metal solution model predictions with compatibility data of niobium with liquid sodium

Theoretical correlations based on the coordination cluster model have been used to obtain the solubility of niobium in liquid sodium as a function of oxygen content. It is shown that the derived equations are useful to provide understanding of a relationship between thermodynamic properties and local ordering in the Na-Nb-O melt. The effect of oxygen in sodium on the compatibility niobium with liquid sodium is discussed in terms of two processes: (1) oxygen level increases the solubility of niobium in liquid sodium, and (2) oxygen enhanced dissolution by liquid sodium has been explained by taking into account the formation of ternary oxide of the alkali metal and niobium.