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3721202 
Journal Article 
NEW DEVELOPMENTS ON REFRACTORY HOLLOWWARE MATERIALS FOR INGOT CASTING 
Rettore, RdeP; Gueguen, E; Zieba, G 
2014 
549-552 
WOS:000348596100094 
Refractory products for ingot casting normally require good thermal shock and high erosion and corrosion resistances. A high thermal shock resistance and erosion resistance is normally achieved by Refractories of the high alumina to silica systems, in which corundum (known by its high mechanical strength) and mullite (known by its low thermal expansion coefficient), are the main mineral phases. To increase hot strength, however, it is necessary to lower the level of impurities, e.g. Fe2O3, TiO2 and alkali, which are normally present in natural raw materials. In this way, a new high alumina material (83% Al2O3), composed by a special synthetic aggregate and a pure matrix was developed. This new refractory material presented 150 degrees C higher T-05 refractoriness under load when compared with fired bauxite bricks (84% Al2O3). Superior thermal shock was also obtained, observed by the higher residual mechanical strength after 10 thermal cycles. To address an improvement in the corrosion resistance, a novel approach was found by introducing 3% to 5% carbon into the refractory matrix. No matter the carbon source type used, practically no corrosion and no sticking between the refractory material and steel was observed. These new developments for refractory hollowware materials can be installed whenever strong operational conditions take place, like high casting temperature and high Manganese containing steels. Some real cases of the utilisation of these new high alumina and high alumina-carbon refractory hollowware materials will be presented and discussed.