Wetting and Spreading Phenomena in Liquid Bismuth-Alkali Halide Systems

Abstract

This investigation is devoted to the study of the features of wetting phenomena in high temperature systems that are promising as environments for processing and disposal of man-made and radioactive wastes. New data on the phase wetting transition in two-phase liquid media have been obtained by analyzing the values of the adhesion of salt melts to liquid metals. The present study is focused on the systems composed of molten alkali halides and liquid bismuth. Their adhesion was calculated using experimental data on the surface tension of metals and salts, as well as the interfacial tension between metals and salts. A regular change in the adhesion work is illustrated depending on the temperature, electrical potential and nature of the contact phases. The transition phenomenon from incomplete wetting to full wetting has been established. It is shown that this transition is facilitated by an increase in temperature, a potential jump in the phase contact plane, and the polarizability of salt phase ions. The potential dependence of the adhesion work near the wetting transition point is described by a power equation with a critical index equal to 1.1.