Physical properties and corrosion resistance of magnesia-calcium hexaaluminate refractories to molten steel

Abstract

The continuous casting tundish serves as the final vessel for molten steel in the smelting process. Resistance to steel corrosion and penetration is critical for clean steel smelting and the durability of working linings. In this study, calcium hexaaluminate (CA6) was selected to gradually replace the commonly used MgO refractory. We analyzed the phase composition, cold modulus of fracture, cold crushing strength, bulk density, porosity, and resistance to molten steel corrosion and penetration of MgO–CA6 refractories. It was observed that the mechanical properties of the material were reduced by the addition of CA6; however, a certain percentage of CA6 and MgO formed a small amount of MgO·Al2O3 at high temperatures to retain its high performance. The materials are less likely to react with [Mn], [Si] and other alloying elements in steel after the addition of CA6 and it exhibits excellent resistance to steel corrosion, which is important for clean steel production and the durability of working linings.