Surface-active additions in liquid metals

Summary The criteria of surface activity found in the literature are discussed in the paper. The differences in the specific heats of sublimation of the dissolved substance and solvent, as well as the differences of full potential barriers, are proposed as new criteria.The reliability of the criteria of surface activity was checked by the experimental data of over a hundred metal systems. The best criteria proved to be the differences between the free surface energies, full potential barriers and specific heats of sublimation of the dissolved substance and the solvent. The conjunction of these criteria is a reliable base for prognosis of the effect of dissolved elements on the surface properties of metal melts.