Improvement of MgO-C Bricks for Thermal Cycling Behavior in Steel Ladle Operation

摘要

Magnesia-carbon materials are widely used in sectors of the steel industry because of their excellent refractory properties. These materials mainly consist of several types of magnesia and graphite, but usually they also include other carbon sources as carbon black and a carbonaceous' binder in their composition. MgO-C bricks exhibit excellent slag corrosion and thermal shock resistance that are the mainly wear mechanisms for slag line of steel ladles in the integrated steel making applications.Magnesia-carbon refractories have a straightforward manufacturing process, comprised by mixing, pressing and curing (~200°C) steps with no pre-firing treatment. Nevertheless, graphite or other carbon sources added to these products can be easily oxidized at temperatures higher than 600°C, According to many investigations, an effective alternative to overcome this problem consists of adding antioxidant compounds to the refractory compositions increasing the porosity reducing the mechanical strength and corrosion resistance of the bricks.