Synthesis of MgO-MgAl2O4 refractory aggregates for application in MgO-C slide plate

This work provides an effective method for synthesis of MgO-MgAl2O4 (MgO-MA) aggregates with good thermal shock resistance (TSR) using lightly calcined magnesia and alpha-Al2O3 micro-powder as the starting materials. The effect of alpha-Al2O3 micro-powder amount and calcination temperature on TSR and microstructure of the syn thesized MgO-MA aggregates was investigated. The optimum amount of alpha-Al2O3 micro-powder was 15 wt%, and the obtained aggregates had the highest density after calcination at 1650 degrees C. The synthesized MgO-MA aggregates had excellent TSR which was attributed to the thermal mismatch of MgO and MA grains as well as the pinning effect of MA grains on the periclase grain boundaries. TSR of MgO-C slide plate materials was improved significantly by introducing appropriate amount of the synthesized MgO-MA aggregates.