Lightweight corundum-spinel ladle wear lining castable with low thermal conductivity

Designing a lightweight wear-lining refractory is of great significance for energy savings and consumption reduction. In this study, an in-house manufactured porous alumina aggregate was selected to replace the commercial tabular alumina aggregate to prepare lightweight corundum-spinel castable (LCSC) for ladle linings. The effect of the porous alumina aggregate on the properties of the corundum-spinel castable was investigated. Compared to tabular alumina, porous alumina possesses higher closed porosity (12.1%) and a small pore size (4.25 mu m). The thermal conductivity of LCSC is 21.5% lower than that of dense castable at 1000 degrees C. Owing to the existence of micropores in the porous alumina, the fabricated corundum-spinel castable showed an improved degree of bonding between the aggregate and matrix. Therefore, the lightweight castable showed higher flexural strength and considerable slag corrosion resistance than the dense castable.