Adsorption mechanism of oxide inclusions by microporous magnesia aggregates in tundish

Abstract The microporous refractory with low thermal conductivity shows a promising application prospect as tundish lining. In this study, the interactions between microporous magnesia aggregates and oxide inclusions in steel were explored. The experimental results and thermodynamic calculation show that the interaction process of microporous magnesia aggregates and oxide inclusions at high temperature can be divided into dissolution, reaction and post-reaction. The microporous magnesia aggregates can absorb the inclusions in steel by reaction and liquid phase penetration. The microporous magnesia aggregates have a strong adsorption for Al2O3 and TiO2. Moreover, the microporous magnesia aggregates mainly absorb SiO2 by penetration, but excessive SiO2 will lead to the serious corrosion of microporous magnesia aggregates.