Enhanced performance of low-carbon MgO-C refractories with nano-sized ZrO2-Al2O3 composite powder

Low-carbon MgO-C refractories are facing great challenges with severe thermal shock and slag corrosion in service. Here, a new approach, based on the incorporation of nano-sized ZrO2-Al2O3 composite powder, is proposed to enhance the thermal shock resistance and slag resistance of such refractories in this work. The results showed that addition of ZrO2-Al2O3 composite powder was helpful for improving their comprehensive performances. Particularly, the thermal shock resistance of the specimen containing 0.5 wt% composite powder was enhanced significantly which was related to the transformation toughening of zirconia and in-situ formation of more spinel phases in the matrix; also, the slag resistance of the corresponding specimen was significantly improved, which was attributed to the optimization of pore structure and formation of much thicker MgO dense layer.

Automated summary

A new approach was proposed in this study to enhance the performance of low-carbon MgO-C refractories by incorporating composite powders. It was found that this method significantly improved the thermal shock and slag resistance of the refractories, attributed to the toughening of zirconia and optimization of pore structure.