Optimization of the Fe-rich Fe-Mn-S ternary phase diagram

Abstract

Phase equilibria in the Fe-rich side of the Fe-Mn-S ternary system were analyzed on the basis of the thermodynamic analysis of the Fe-FeS, Fe-Mn, Mn-MnS and Fe-FeS-MnS-Mn systems. The Gibbs energy of individual phases was approximated by the sublattice model, assuming S to be interstitial atoms. Most of the experimental information was well reproduced by the present set of thermodynamic descriptions. The present analysis is useful for understanding sulfide formation during solidification, precipitation in solids, and the cause of the so-called hot shortness in mild steels.