Evaluation of surface tension and adsorption for liquid Fe-S alloys

Abstract

Surface tension of liquid iron is strongly influenced by the adsorption of sulfur. In this study, surface tensions of liquid Fe-S alloys at 1 823 K were measured by the sessile drop technique in a purified argon atmosphere. Experimental results were compared with the model based on Butler's equations considering the effect of size and interactions of the adsorbed elements assuming that the system was composed of Fe-"FeS" binary. The model could evaluate the surface tension and the adsorption of sulfur more reasonably rather than a simple ideal adsorption model. In the calculations, excess free energy expanded by Margules' series over the entire composition range of Fe-FeS system was used.