Effect of Mg on the evolution of non-metallic inclusions in Mn–Si–Ti deoxidised steel during solidification: experiments and thermodynamic calculations

Abstract

The effects of Mg on the evolution of non-metallic inclusions in Mn–Si–Ti deoxidised steels during solidification were investigated in a study based on experiments and thermodynamic calculations. The inclusions were composed of the MgO–MnO–Ti₂O₃–TiO₂ oxide, MnS, and TiN. With the increase of Mg concentration in steels, the phases of oxide inclusions were changed, in the order of pseudobrookite (Ti₃O₅–MnTi₂O₅), ilmenite (MgTiO₃–MnTiO₃–Ti₂O₃), spinel (Mg₂TiO₄–MgTi₂O₄–Mn₂TiO₄–MnTi₂O₄) and MgO. Thermodynamic calculations for inclusion evolutions were in good agreement with the experimental results.