Interfacial Behaviour in Ferroalloys: The Influence of FeMn Slag Composition

Abstract

AbstractThe present study investigated the interfacial interaction between FeMn alloy and slags of different compositions and basicity from 0.4 to 1.2 in a sessile drop furnace. Interfacial tension between the FeMn alloy and the slags was measured, and the results were analyzed to assess the sensitivity of the applied methodology. The measurement of the interfacial tension was based on combining the results from experiments, multiphase flow simulations in OpenFOAM, equilibrium calculations in FactSage, and calculation of slag density and surface tension based on numerical models. The results demonstrate that the interfacial tension between the FeMn alloy and slag increases with the slag basicity. It was found that the addition of Al$$_{2}$$ 2 O$$_{3}$$ 3 to the slag with basicity of 0.8 and 1.2 increases the interfacial tension, while increasing MnO content from 30.0 to 45.0 wt pct does not have any statistically significant influence on the interfacial tension. EPMA analysis of slag and FeMn phases showed that slags at lower basicities and the FeMn alloy form a metal–slag emulsion due to the destabilization of the interface induced by chemical reactions, partial reduction of SiO$$_{2}$$ 2 in the slag and the mass transfer of Si across the metal–slag interface.