Thermodynamic model for prediction of slag-steel-inclusion reactions of 304 stainless steels

Abstract

A thermodynamic model was developed to predict slag-steel-inclusion reactions of 304 stainless steels. The dissolved aluminum in the steel, the sulfur distribution ratio and the composition of inclusions equilibrated with varying slags were predicted using the current model. The model can also be widely used to predict the liquid fraction of inclusions. For Al-killed 304 stainless steels, the optimized composition of CaO-Al2O3-SiO2-MgO slags is proposed to modify solid Al2O3 inclusions to liquid CaO-Al2O3-MgO at 1 873 K. For Si-Mn-killed 304 stainless steels, the optimized composition of CaO-SiO2-MgO-Al2O3-20%CaF2 slags is suggested to suppress the formation of Al2O3-MgO in SiO2-CaO-MnO-MgO-Al2O3 inclusions and lower their melting temperatures.