Vacuum-oxygen decarburisation (VOD) is a secondary refining step in the production of stainless steel. Direct-bonded magnesia-chromite refractories are widely used as the working lining material in VOD ladles. However, due to the high costs and the environmental risks related to these materials, major efforts are required to replace them with alternative refractory types. Magnesia-carbon bricks have a particular potential in this respect. The reported advantages of magnesia-carbon bricks in non-vacuum environments are their excellent thermal shock resistance, the high slag corrosion resistance of the carbon component and the in-situ formation of a protective, magnesia layer. However the feasibility to extend the use of magnesia-carbon bricks to AOD and VOD processes has not been thoroughly investigated. The limited amount of available literature suggests a negative answer. For this purpose, various magnesia-carbon brick types were tested in industrial linings at the U&A Belgium stainless steel company. We report on their degradation mechanisms during the VOD process and illustrate in which ladle zones they can be used.
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