Characterization of the physical properties of a self-flowing low-cement castable based on white-fused alumina

A white-fused low cement refractory castable was prepared from pure refractories that consisted of 77 wt.% white fused alumina, 10 wt.% calcined alumina, 8 wt.% microsilica, 5 wt.% cement and 0.05 wt.% dispersant. Optimum self-leveling flowability was achieved by using 5.6 wt.% water. To determine the effect of the firing temperature on the white-fused low cement refractory castable, studies of apparent porosity (AP), bulk density (BD), water absorption (WA), cold crushing strength (CCS), hardness, X-ray diffraction (XRD) and microstructural-based evaluation using electron probe microanalyser (EPMA) were performed. The present castable heat treated at 1500 °C for 2 h exhibited the following properties: the AP -14%, the BD -3.12 gem^-3, the WA -2.5%, the CCS -2000 kgem^-2 and the hardness -3185 kgmm². The new white-fused alumina castable presents unique properties that would make it desirable to use in industrial refractory applications.