Abstract: A porous refractory cast material contains a closed refractory aggregate fraction having a minimum particle size and a maximum particle size; the ratio of maximum particle size to minimum particle size is 10:1 or less. This closed refractory aggregate fraction comprises all of the porous refractory cast material having a particle diameter greater than 0.1 mm. The porous refractory cast material also contains a binder phase containing refractory selected from calcium aluminate cement, alumina phosphate, hydratable alumina, colloidal silica and combinations thereof. Also disclosed is a metallurgical vessel with an interior lining incorporating the porous refractory cast material.

Abstract: A porous refractory cast material contains a closed refractory aggregate fraction having a minimum particle size and a maximum particle size; the ratio of maximum particle size to minimum particle size is 10:1 or less. This closed refractory aggregate fraction comprises all of the porous refractory cast material having a particle diameter greater than 0.1 mm. The porous refractory cast material also contains a binder phase containing refractory selected from calcium aluminate cement, alumina phosphate, hydratable alumina, colloidal silica and combinations thereof. Also disclosed is a metallurgical vessel with an interior lining incorporating the porous refractory cast material.

Abstract: A porous refractory cast material contains a closed refractory aggregate fraction having a minimum particle size and a maximum particle size; the ratio of maximum particle size to minimum particle size is 10:1 or less. This closed refractory aggregate fraction comprises all of the porous refractory cast material having a particle diameter greater than 0.1 mm. The porous refractory cast material also contains a binder phase containing refractory selected from calcium aluminate cement, alumina phosphate, hydratable alumina, colloidal silica and combinations thereof. Also disclosed is a metallurgical vessel with an interior lining incorporating the porous refractory cast material.

Abstract: In the continuous casting of molten metal, the invention describes a refractory article for reducing deposition of inclusions on a surface contacting the stream of molten metal. The article comprises a first composition and a second composition on at least a portion of the contacting surface. The second composition includes a resin-bonded refractory composition comprising a refractory aggregate and a reactive metal. The resin-bonded refractory composition reduces deposition of inclusions relative to standard carbon-bonded or castable refractories. The second composition is particularly effective as a nose of a stopper rod or a liner for a nozzle, shroud or slide gate plate.

Abstract: In the continuous casting of molten metal, the invention describes a refractory article for reducing deposition of inclusions on a surface contacting the stream of molten metal. The article comprises a first composition and a second composition on at least a portion of the contacting surface. The second composition includes a resin-bonded refractory composition comprising a refractory aggregate and a reactive metal. The resin-bonded refractory composition reduces deposition of inclusions relative to standard carbon-bonded or castable refractories. The second composition is particularly effective as a nose of a stopper rod or a liner for a nozzle, shroud or slide gate plate.

Abstract: A dense carbon free surface is provided on a carbon bonded refractory shape which is particularly useful as a pouring tube liner to prevent the formation and build-up of alumina particles which may cause blockage of the tube. The carbon free, dense layer is also hard and erosion resistant making it ideal for use in other applications such as stopper rod noses. The material comprises a refractory mix having a major component of refractory oxides such as alumina and zirconia-mullite. Less than 10 wt. % carbon in the form of graphite and binder is in the mix plus about 2-5 wt. % of a metal such as silicon and an effective mount of sintering aids is also present. The pressed shape is preheated to a temperature of 1000.degree. -1400.degree. C. in air to oxidize the exposed surface of the shape and then to sinter the oxidized surface to form the desired dense, carbon free surface over the entire shape or on selected surface portions thereof.

Abstract: The invention concerns a fired magnesia-carbon shape having a combination of properties making it especially suitable for slide gate plates, inserts for such plates and for pouring nozzles useful in casting aggressive steels. The fired refractory shape is formed from a batch consisting essentially of, by weight percent,2 to 8 finely divided graphite (natural or synthetic);3 to 8 aluminum metal powder;1 to 5 of finely divided silica and/or a silicon yielding powder;an effective amount of carbon bond forming resins;and the balance coarse and fine magnesia grains.The magnesia grains should contain less than about 0.02 weight percent boron oxide. After firing, the shape is characterized by a carbon bonding system including a spinel (magnesia-alumina) phase plus aluminum carbide bonding the magnesia-carbon matrix. The refractory shape is preferably carbon impregnated after firing to further enhance its properties.