The corrosion and infiltration of refractory by chemical waste liquid rich in alkali ions such as potassium and sodium are the main cause of material damage. Their service life varies with the material systems. In this work, three kinds of aluminum-silicon refractories were prepared by using alumina, mullite, andalusite and clay as raw materials. Static crucible method was used to carry out alkali corrosion test at 900 ℃, and Na₂CO₃ was used as corrosive agent. The phases and microstructures of the residual crucibles were examined by means of X-ray diffraction (XRD) and scanning electron microscope (SEM). The wetting process of molten Na₂CO₃ on refractory was detected by high temperature contact angle measurement system. The corrosion and infiltration resistance of refractories were discussed based on their wettability. The results show that corundum-mullite system has weak ability to resist corrosion and infiltration of the molten Na₂CO_3. By contrast, high-purity mullite system has better performance. The mullite transformed from andalusite can improve its infiltration resistance. The infiltration of molten Na₂CO₃ into refractory is related to its wetting ability, they both determine the damage degree of refractories.

Keywords: Aluminum-silicon refractories, Corrosion, Infiltration, Wettability.