Corrosion Study of MgO-C Bricks in Contact with a Steelmaking Slag

The MgO-C bricks are extensively used as lining work on different steel containers. Due to the high temperatures of the process, these refractories are subjected to severe wear and corrosion processes, principally in the area of contact with the slag. These slags have variable contents of CaO, SiO2, Al2O3, MgO and FeO, varying in composition according to the process stage. In this paper, cup tests were performed at 1650 °C during 2 hours in air, using three kinds of commercial MgO-C bricks. They were put in contact with a high basicity slag. The corrosion degree and decarburization level sufferered by the refractories were analyzed and compared. Microstructural observations were performed in order to postulate the probable corrosion mechanisms acting on each material.