Abstract: The present invention provides a carbon-containing refractory composition characterized by containing 0.1-10 parts by weight of silicon hexaboride in 100 parts by weight of refractory material comprising 3-95 parts by weight of carbonaceous material such as graphite and 97-5 parts by weight of refractory aggregate.In the carbon-containing refractory composition of the present invention, silicon hexaboride is oxidized producing boron oxide on the surface of the refractory at a high temperature during operation, and the surface of the refractory is covered by the formation of a highly viscous molten liquid like kotoite (3 MgO.B.sub.2 O.sub.3), for example, which is formed from the components of the refractory, such as MgO, for example, thus particles of carbonaceous material such as graphite can be protected from oxidation.

Abstract: A refractory for use in casting of molten metal which essentially comprises refractory material comprising corundum and monoclinic zirconia as principal mineral phase and including Al.sub.2 O.sub.3 and ZrO.sub.2, silicon-containing powder and carbon-containing powder and which optionally includes first additional refractory material comprising mullite, baddellite and corundum as principal mineral phase and including Al.sub.2 O.sub.3, ZrO.sub.2 and SiO.sub.2, one or more second additional refractory materials and/or alumina.

Abstract: Novel aqueous inorganic particle slurries, wherein some of the particles have had their charge potential altered to a sufficient extent to prevent segregation or settling of the particles, are described, along with a method for their preparation. The method of forming slurries of negatively charged particles comprises treating some of the particles with a cationic agent to reduce their charge and mixing these treated particles with the remainder of the particles to form a thick, cream-like flowable composition of a thixotropic nature. When slurries of positively charged particles are to be formed, an anionic agent is used instead of a cationic agent.

Abstract: An improved alumina reduction cell is disclosed. Vapor barriers, formed from a castable refractory and a silicon carbide mortar protect the bottom and sidewall insulation material of the cell from attack by the corrosive materials contained within the cell.

Abstract: The vitreous carbon disclosed herein is prepared from intimate uniform mixtures of powder or otherwise blendable form of 20-80% by weight of a solid phenolic-aldehyde Novolak resin and of 20-80% by weight of a solid phenolic-aldehyde resol resin, the percentages being based on the combined weight of the Novolak and resol resins, and the aldehyde in said Novolak resin comprising at least 50 molar percent, preferably substantially 100 percent, furfuraldehyde, together with a carbonaceous filler, preferably graphite, in a proportion as high as 76% by weight based on the total composition. Generally the graphite may comprise 30-70%, advantageously 35-65% and preferably 40-60% of the molding composition. The vitreous carbon is improved in electrical properties and in the capability of being shaped into large thin plates which are much more stress-free than otherwise produced.

Abstract: The invention concerns a fired refractory product based on refractory grains and binder, and process for the production thereof.The refractory product comprises a charge of refractory grains belonging to the group comprising carbonaceous products such as anthracite, natural graphite, artificial graphite, amorphous carbon, coke, refractory compounds known as RHM such as silicon carbide and refractory oxides such as alumina, corundum, magnesia, silica and chromium oxide, taken separately, in mixture or in combination; said grains are secured together by a cement based on a coked carbonaceous product and metal silicon in powder form; and the final proportion of metal silicon is from 1 to 15.8% and preferably from 3 to 10.5%.The product is intended for the manufacture of side linings for tanks for the production of aluminum by igneous electrolysis, and linings for blast furnaces and electric furnaces for electrometallurgy operations.

Abstract: An elemental carbon-containing refractory composition having superior erosion and oxidation resistance due to the addition of prescribed amounts of boron carbide.

Abstract: Thin, flaky graphite-containing refractories are obtained by refining and processing naturally occurring minerals and possess a specific size of the extent of the surface of a flaky layer and a specific thickness of a flake. Such flaky graphite-containing refractories exhibit high endurance and are effective as lining materials particularly for steel making furnaces.

Abstract: A spout-filling mass which is retained in place by a slider in the pouring spout of a metal-casting ladle consists essentially of 35 to 65% by weight chromite, (chromium ore with 42 to 45% Cr.sub.2 O.sub.3), 3 to 25% by weight carbon and the balance quartz sand. The mass, which fills the cylindrical portion of the spout, is formed into a pile on the floor of the ladle above the spout and upon contact with the molten metal fuses into a thin shell which, upon movement of the slider to bring its opening into registry with the spout, is ruptured by the molten metal after the underlying support for the shell is discharged through the spout.

Abstract: Carbon in the form of graphite is commonly used in refractories for metallurgical purposes because of its ability to increase resistance to corrosion. However, if the graphite in the refractory becomes oxidized, it greatly loses this ability. For this reason, it is very important for a refractory to have good resistance to oxidation, but there are at present no refractories fully satisfactory from the standpoints of resistance to oxidation and hot strength.The present invention is a carbon-containing refractory having excellent resistance to oxidation and hot strength. These favorable properties are obtained by the addition in the refractory of both boron carbide and metal powder, the powder comprising at least one metal selected from Al, Si, Fe, and Ni.

Abstract: A more pressable composition for making graphitic refractory brick from oxide aggregate with a carbon bond is obtained when the refractory oxide aggregate is substantially all coarser than 0.15 mm (+100 mesh), preferably coarser than 0.2 mm (+65 mesh), and most preferably coarser than 0.4 mm (+35 mesh), and the matrix is entirely carbonaceous material, such as graphite, particularly flake graphite, resin, particularly a phenol formaldehyde resin, together with such other carbonaceous materials as carbon black, calcined coke, anthracite, and the like.

Abstract: Matter for protecting graphite electrodes of electric arc furnaces, e.g. for steelmaking, to reduce loss of graphite by oxidation, comprises particles containing both a graphite-wetting fusible matrix material and a refractory filler. Methods of making and using the particulate matter are disclosed.

Abstract: Carbon bonded refractory brick containing 1 to 6% by weight liquid thermosetting resin binder consisting of polyhydroxydiphenyl resin and a curing agent and the balance being refractory aggregate.

Abstract: A refractory shape having improved resistance to erosion in metal melting vessels and high modulus of rupture, comprising an anhydrous refractory material, an anhydrous organic binder, from 0.3% to about 30% finely divided elemental carbon having a particle size ranging from 0.01 to about 1 mm, and from 0.3% to about 10% particulate elemental magnesium, based on the weight of the refractory shape. Addition of both elemental carbon and elemental magnesium results in a synergistic improvement in slag erosion resistance.

Abstract: An amorphous refractory settable at low temperatures comprises a usual refractory material, a metal powder in an amount of 0.5 to 5% by weight based on the whole amount of the refractory and serving as a sintering agent and a phosphate glass powder in an amount of 0.5 to 3% by weight based on the whole amount and serving as a sintering and setting agent. A pitch powder can be further incorporated in the refractory in an amount of 0.1 to 6% by weight based on the whole amount to render the refractory settable more effectively at low temperatures. The refractory is usable in the form of a dry powder without using any water or other liquid for lining troughs and containers for molten metals.

Abstract: Flaky .beta.-SiC mainly composed of .beta.-SiC which is obtained from an organic silicon polymer containing the carbon and silicon atoms as the major skeletal component and the method for producing such flaky .beta.-SiC are disclosed. Such .beta.-SiC is especially utilized as the starting material for ceramics having a laminar structure as well as for the refractories. The ceramics and refractories provided with such .beta.-SiC have excellent resistance to thermal shock, to thermal fatigue as well as to oxidation.

Abstract: A non-aqueous, thermoplastic refractory binder comprising a resinous petroleum residue having a softening point ranging from 100.degree. F. to 150.degree. F. (38.degree.-65.degree. C.), being less than 2% insoluble in benzene, and preferably having a fixed carbon content of between 30 and 40%, and refractories made therewith.

Abstract: A laminated composite and a method for forming the composite by chemical vapor deposition. The composite includes a layer of sialon and a material to which the layer is bonded. The method includes the steps of exposing a surface of the material to an ammonia containing atmosphere; heating the surface to at least about 1200.degree. C.; and impinging a gas containing in a flowing atmosphere of air N.sub.2, SiCl.sub.4, and AlCl.sub.3 on the surface.

Abstract: A lightweight aggregate comprising an alkali metal borosilicoaluminate, is in the form of discrete, porous and expanded particles of approximately spherical shape, has a specific weight between about 60 and about 600 kg/m.sup.3 and a compression strength of from about 140 kg/cm.sup.2 up to about 250 kg/cm.sup.2, is highly insoluble in water, steam, acids or bases, has a melting temperature above 1500.degree. C. and a low alkalinity, and chemically comprises a homogeneous admixture of acid, basic and amphoteric oxides.A highly preferred embodiment of the aggregate has an M.sub.2 O/B.sub.2 O.sub.3 ratio between about 3:1 to about 6:1, where M is an alkali metal.

Abstract: The invention relates to precluding the shortcomings intrinsic to the conventional unburned carbon-containing refractory bricks, i.e., oxidization under high temperature conditions and the incidental decarbonization, the phenomenon of exfoliation and detachment of the fragile layers, and more particularly to obtaining thereby unburned carbon-containing refractory bricks having the high properties by causing refractory brick material comprising substantially more than 1 weight % carbon to contain 1-10 weight % aluminum powder and/or magnesium powder each independently or in a mixture thereof, and/or 0.5-6 weight % silicon powder.

Abstract: A blanket powder for covering a molten metal bath in order to prevent oxidation and to provide heat insulation contains, in addition to the ash of cereal hulls, approximately 5 to 50% by weight of non-calcined cereal hulls. The powder can thus be transported and handled without any attendant danger of contaminating dust formation and has enhanced heat-insulating power.

Abstract: The vitreous carbon disclosed herein is prepared from intimate uniform mixtures of powder or otherwise blendable form of 20-80% by weight of a solid phenolic-aldehyde Novolak resin and of 20-80% by weight of a solid phenolic-aldehyde resol resin, the percentages being based on the combined weight of the Novolak and resol resins, and the aldehyde in said Novolak resin comprising at least 50 molar percent, preferably substantially 100 percent, furfuraldehyde, together with a carbonaceous filler, preferably graphite, in a proportion as high as 76% by weight based on the total composition. Generally the graphite may comprise 30-70%, advantageously 35-65% and preferably 40-60% of the molding condition. The vitreous carbon is improved in electrical properties and in the capability of being shaped into large thin plates which are much more stress-free than otherwise produced.