Reaction Behaviors of Al-Killed Medium-Manganese Steel with Different Refractories

Abstract

In order to understand the reaction mechanism between medium-manganese steel and different refractories, some laboratory experiments were carried out at 1873 K (1600 °C). Three types of refractory plates (Al2O3, MgO, and MgO·Al2O3) were used. The results show that Mn in liquid medium-manganese steel does not react easily with the Al2O3 refractory, but can react with the MgO refractory to generate a (Mn, Mg)O layer at the boundary between the refractory plate and liquid steel. After the formation of (Mn, Mg)O, a layer of (Mn, Mg)O·Al2O3 spinel is also formed at the edge of the MgO refractory. Similar to the MgO refractory, the dissolved Mn can react with the MgO·Al2O3 refractory as well, and a layer of (Mn, Mg)O·Al2O3 was also detected after reaction. It was found that the formation of (Mn, Mg)O·Al2O3 at the edge of the refractory is a source of (Mn, Mg)O·Al2O3 inclusions in liquid steel. The flush-off of the (Mn, Mg)O·Al2O3 layer would result in the formation of (Mn, Mg)O·Al2O3 inclusions.