Interaction between refractory for refining ladle and low-carbon low-silicon Al-killed molten steel

Abstract

To investigate the interaction between low-carbon low-silicon Al-killed molten steel and the refractory materials employed in refining ladles, the study focused on the interface reaction between molten steel with a composition of Fe-0.03C-0.01Si-0.2Mn-0.03Al (wt%) and the four types of refractory materials used in different positions of refining ladles at 1873 K. The results show that different interface layers form after 60 min of contact between the refractory materials and the molten steel. The MgO-C refractory generates a dense MgO layer, the MgO-Al2O3 refractory produces a (Fe, Mg)Al2O4 layer, the Al2O3-SiC refractory forms a Mg Al2O4 layer rich in Si, and the MgO-Al2O3-C refractory generates a MgAl2O4 spinel layer. The average content of Mg at the interface decreases in the following order: MgO-C, MgO-Al2O3-C, Al2O3-SiC and MgO-Al2O3 refractory, and SiC available in Al2O3-SiC refractory supplies more Si to the interface. The thermodynamic simulation is consistent with the actual results.