The Slag Resistance Of Magnesia Castable

The influence of bauxite based 3 -Sialon, graphite pellets and their composite on slag resistance properties of magnesia castables were studied by static crucible method and revolution dipping method. Magnesia castables used in the tests were prepared, using fused magnesite as aggregate, fused magnesite fine, ultra fine α -Al₂O₃ and micro-silica as matrixes, MgO-SiO₂-H₂O as bonding system, and additives with varying contents substitute corresponding fused alumina respectively.Main studying work includes: (1) the influence of nonoxide on physics properties of magnesia castables at room temperature; (2) the influence of Sialon on slag resistance of magnesia castables; (3) the influence of graphite pellets on slag resistance of magnesia castables; (4) the influence of composite Sialon and graphite pellets on slag resistance of magnesia castables; (5) the relationship between microstructure and slag resistance of magnesia castables.The results show that the MOR and CCS of magnesia castables at room temperature increase with appropriate Sialon addition, and the highest MOR value of specimen with 5wt% Sialon addition would be gained. The MOR value keeps unchange, and the CCS value of specimen with 5wt% graphite pellets addition decreases.The results of static crucible test show that slag resistance of magnesia castables with appropriate nonoxide addition would be improved; Slag resistance of magnesia castables with 2.5wt% Sialon addition would be improved obviously; Slag resistance of magnesia castables with 4wt% graphite pellets addition would be increased; Slag resistance of magnesia castables with 2wt% composite Sialon and graphite pellets addition would be enhanced. When graphite pellets or composite Sialon and graphie pellets addition is more than 6wt%, slag resistance gets worse because of the exacerbation of oxidation and loosen of specimens structure.The study results by revolution dipping test show that the sequencing of corrosion resistance after revolution dipping slag corrosion in 25 minutes is: the specimen with 4% composite Sialon and graphite pellets > the specimen with 5% Sialon addition > the specimen without Sialon addition>the specimen with 4% graphite pellets. The corrosion...