Effect of magnesium aluminate spinel content of porous aggregates on cement clinker corrosion and adherence properties of lightweight periclase-spinel refractories

Abstract The present study investigated five lightweight periclase-magnesium aluminate spinel refractories containing porous spinel aggregates with a varying spinel content. The cement clinker resistance and adherence properties of the lightweight refractories were analyzed by a static crucible test and a sandwich test, respectively. The effect of the spinel content of the aggregates (SCA) on the cement clinker resistance and adherence properties was investigated with SEM, EDS and with the thermochemical software FactSage®. The reaction between the spinel in the refractories with the cement clinker caused the formation of a liquid phase. This liquid phase determined the adherence properties of the refractories and also affected their cement clinker resistance. When the SCA was 0–25 wt%, the refractories had a high corrosion resistance and the cement clinker successfully adhered to the refractories. Yet, when the spinel content was between 50 wt% and 100 wt%, excessive liquid phase formation seriously impaired the refractories. Consequently, the optimized periclase-spinel refractories contained porous aggregates with 25 wt% spinel, which resulted in a high corrosion resistance together with an excellent adherence ability regarding the cement clinker.