COMPUTATIONAL AND THEORETICAL EVALUATION OF THE PARAMETERS RESPONSIBLE FOR THE COMPATIBILITY OF METALLIC MATERIALS WITH THE LIQUID SN-20% LI ALLOY

Abstract

The main features of the thermodynamic evaluation of the parameters responsible for compatibility of metal materials with liquid Sn-20%Li alloy are considered in the article. Interest in the study of the physicochemical properties of liquid lithium-tin alloys is associated with the prospects for their use in plasma facing components of tokamaks. The main advantages of capillary-porous systems with a liquid metal in comparison with solid materials are their resistance to degradation of properties under tokamak conditions and the ability to self-repair the surface. Due to the fact that liquid tin is a very corrosive metal with respect to many structural materials, the advancement of liquid Li-Sn alloys is largely constrained by the lack of systematic studies of the corrosion resistance of structural materials in contact with these liquid alloys. To calculate the temperature dependences of the solubility of metals in the liquid Sn-20% Li alloy, the method of thermodynamic modeling was used, which included the following steps: (1) selection of models for the Gibbs energy functions; (2) selection and evaluation of input data; (3) optimization of model parameters; (4) calculations and comparisons. Using information on the excess Gibbs energies of mixing for the liquid phase in the form of the Redlich-Kister polynomial decomposition for the corresponding binary systems, the temperature dependences of the solubility of nickel, iron, chromium, molybdenum, and tungsten in the liquid alloy Sn-20% Li were calculated by thermodynamic modeling.