CORROSION MECHANISM OF MgO-C LADLE REFRACTORY IN CONTACT WITH MgO-CaO-Al_2O_3-SiO_2 SLAG

摘要

The corrosion resistance and corroded microstructure of MgO-C refractory in molten slag are investigated by immersion test in muffle furnace at 1600 C . The microstructure and chemical compositions of the specimens after erosion experiment are characterized by scanning electron microscope (SEM) and energy dispersive X-ray (EDX). The results confirm that the oxidation of graphite is the most important degradation mode of MgO-C refractory. The structure of the refractory material is damaged due to the decrease of graphite, as a result, the periclase substrate reacts with the molten slag directly. The corrosion process is controlled by the dissolution of the refractory materials into slag, low melting point oxides are therefore generated which lead to the damage of MgO-C refractory finally.