Abstract: The present invention pertains to a refractory ceramic mass, consisting of a pure magnesia component A and a component B, which consists of granules of pure magnesia, wherein the magnesia granules of component B have a ceating consisting of a refractory material whose granule size is fine compared with that of the magnesia granules and is chemically extensively inert with respect to the magnesia granule or reacts with the magnesia granule and/or itself consists of a plurality of components that are chemically reactive with one another.

Abstract: The present invention pertains to a refractory ceramic mass, consisting of 50 to 97 wt. % of sintered MgO as well as 3 to 50 wt. % of a spinel of the hercynite type.

Abstract: Cordierite honeycomb ceramics comprises a cordierite phase as a main ingredient. A value of [Fe.sub.2 O.sub.3 wt %/(MgO wt %+Fe.sub.2 O.sub.3 wt %)].times.100 is 2-10, where a ferric component is calculated as Fe.sub.2 O.sub.3. A thermal expansion coefficient of the cordierite honeycomb ceramics is less than 0.5.times.10.sup.-6 /.degree. C. within a temperature range of 40.degree.-800.degree. C. in a direction parallel to a flow passage of a honeycomb body. In the cordierite honeycomb ceramics including a ferric component, a ferric component is added from a talc as raw materials. The cordierite honeycomb ceramics having a low thermal expansion coefficient is obtained by mixing raw materials for cordierite generation to obtain a batch, extruding the batch into a honeycomb formed body, drying the honeycomb formed body, and firing the dried honeycomb formed body at a temperature range of 1350.degree.-1450.degree. C. After that, the sintered honeycomb body is immersed in an acid solution if necessary.

Abstract: A firing underlying board having a long use life free from thermal expansion and which does not cause twisting of ribs, deformation of an end face, color change or cracking in a honeycomb structural body fired on the underlying board. The firing underlying board is composed mainly of 55-85 wt % of cordierite and 15-45 wt % of mullite. The firing underlying board is used to fire green ceramic honeycomb structural bodies placed thereon.

Abstract: A ceramic composition which includes Pb(Mg.sub.1/3 Nb.sub.2/3)O.sub.3 or the oxide precursors thereof, in admixture with barium copper oxide of the formula BaCuO.sub.2 as a sinter aid therefor. The compositions do not contain any free lead oxide and have high dielectric constants, e.g. above 8000, and low loss factors, e.g. below 3%.

Abstract: Method for the production of sintered dolomite, wherein at least carbonate material is ground into particles, formed into a predetermined shape, such as briquettes, deacidified and then heated to a predetermined temperature.

Abstract: An aluminum titanate ceramic has as main crystalline phases, a crystalline phase of aluminum titanate and a solid solution thereof, a crystalline phase of mullite and a crystalline phase of rare earth titanate represented by RE.sub.2 Ti.sub.2 O.sub.7 (RE represents Y, Yb, Er, Dy, Ho, Tm or Lu). The aluminum titanate ceramic is superior in casting property and has high heat cycle durability.

Abstract: A self-fluxing binder composition for use in the pelletization of an ore concentrate, especially iron ore concentrates. The composition comprises from 50 to 98% by weight of one or more carrier having a high surface area, and from 2 to 50% by weight of a water soluble organic enhancer. The carrier is selected from the group consisting of natural and synthetic magnesium and/or calcium bearing minerals and preferably consists of synthetic, fibrous-like forsterite. The enhancer is selected amongst the natural polysaccharides, of high viscosity, and more preferably amongst the natural gums of high viscosity such as the guar or xanthan gum and amongst starch and is derivatives. The use of such a self-fluxing binder composition improves the properties of the green and dry pellets and makes them more easy to handle, as compared to those produced with other conventional binders. Moreover, the pellets that are produced with such a binder composition have improved metallurgical properties.

Abstract: A process and apparatus are provided for breaking the glass components of articles comprised of glass and nonglass components and liberating the glass components from the nonglass components by subjecting the articles to controlled vibrations sufficient to break the glass without breaking the nonglass components. The apparatus is a vibratory device having a screen deck and a plate deck. The screen deck has holes through which the broken glass falls to the plate deck. The nonglass components remain on the screen deck. Thereafter, the nonglass components are removed by one or more of a variety of means. The glass may be further processed by cleaning, rinsing and further crushing to size the glass pieces. Glass of different types may optionally be separated by taking advantage of the differences in specific gravities between glass types.

Abstract: Method for the production of sintered dolomite, wherein at least carbonate material is ground into particles, formed into a predetermined shape, such as briquettes, deacidified and then heated to a predetermined temperature.

Abstract: A magnesia-alumina type spinel clinker contains Fe.sub.2 O.sub.3 and TiO.sub.2 at boundaries between crystal grains, and a refractory produced by using the clinker has excellent corrosion resistance and cement coating properties. The refractory can thus be applied to the fields of cement rotary kiln refractories, refractories for iron making, steel making and nonferrous refining and the like.

Abstract: A magnesia-based sintered body of a homogeneous composition having a porosity lower than 1% and a hydrateability lower than 0.3%, said sintered body having a chemical composition comprising 70 to 99.9% by weight of magnesia and 30 to 0.1% by weight of at least one oxide selected from the group consisting of titanium oxide, aluminum oxide, ferric oxide, phosphorus pentoxide, yttrium oxide, barium oxide, boron oxide, calcium oxide and lithium oxide. The sintered body is obtained by molding a powdery mixture of magnesia and the oxide other than magnesia.

Abstract: A process for producing a high density ceramic of perovskite represented by the formula:ABO.sub.

Abstract: The ceramic sinter is composed of a metal oxide such as ZrO.sub.2 and 10-90 vol. % of metal fluoride which is selected from the group having not less than 2.5 electronegativity difference between fluoride and the metal element.The ceramic sinter has a thermal expansion coefficient of 15-20.times.10.sup.-6 /.degree.C. and is suitable for bonding with general use metals such as stainless steel to form a composite body of the ceramic sinter and the metal without causing a substantial thermal stress at the juncture thereof.

Abstract: Sprayable aqueous insulating liner compositions for metal casting vessels such as permanent refractory lined tundishes are disclosed that contain a water insoluble and hydration resistant particulate refractory grain containing MgO, organic binder and fibers, with the composition being substantially free of water soluble alkali and alkaline earth metal oxides that would migrate during drying with the water to degrade the permanent refractory lining.

Abstract: A process is described for the preparation of a ceramic green body by hydrolyzing at least one alkoxide selected from each of two specified groups to form a dispersion of their reaction product, concentrating the dispersion to a sediment without drying it, and admixing a binder and a plasticizer with the sediment to make a ceramic slip formulation. A release agent can optionally be admixed. The slip formulation is then cast as a ceramic green body. The proportions of alkoxides can be adjusted, as desired, to produce a ceramic green body which is dielectric and useful for microcapacitors or as a conductor.

Abstract: A refractory composition which is suitable for forming a sliding gate to be used at the bottom of a ladle or tundish is provided. The refractory composition comprises 10 to 30 parts by weight of an alumina-magnesia spinel material containing 40 to 70% by weight of Al.sub.2 O.sub.3, 25 to 60% by weight of MgO and 10% or less of impurities, and 70 to 90 parts by weight of a magnesia material containing at least 90% by weight of MgO, wherein the composition contains 10 to 25% by weight of Al.sub.2 O.sub.3 and 75 to 90% by weight of MgO. 1 to 10 parts by weight of Al.sub.2 O.sub.3 material may be further added together with the alumina-magnesia spinel material and the magnesia material, to form the refractory composition.

Abstract: Heavy ceramic shaped material with a content of at least one of the components magnesia, fired dolomite, chromite and spinel, characterized by a microcrack system substantially homogeneously distributed in the shaped material structure, as well as process for producing such a heavy ceramic shaped material and the use thereof.

Abstract: Ultrafine particles of ceramic or metallic material are obtained at low temperatures from a nitrate source capable of endothermic decomposition by molecularly combining under a nitrogen atmosphere the nitrate source with an inorganic reducing fuel compound, such as hydrazine, to provide a chemical precursor for the ceramic or metallic material and then exothermically decomposing the precursor in a controlled atmosphere by heating to a temperature up to about 200.degree. C. below the endothermic decomposition temperature of the nitrate source. The nitrate source is a metal nitrate or a mixture of nitrate salts. Ferrite particles are recovered when the nitrate source is a mixture of nitrate salts containing ferric nitrate in a 2:1 molar ratio with at least one additional metal nitrate.

Abstract: Preparation of a ceramic green body by hydrolyzing two groups of alkoxides to form a dispersion of their reaction product, concentrating the dispersion to a sediment without drying it, and admixing a binder solution, plasticizer and release agent with the sediment to make a ceramic slip formulation. The slip formulation is then cast as a ceramic green body. The proportions of alkoxides can be adjusted to produce a ceramic green body which is dielectric and useful for microcapacitors.

Abstract: Magnesium oxide ceramic bodies may be strengthened by inclusion of zirconium oxide particles, and may be further sintered to a density approaching theoretical density by conventional sintering techniques by inclusion of sintering aids, such as manganese oxide and iron oxide.

Abstract: Refractory lining for e.g. casting boxes comprising a refractory matrix and precipitated silica, the silica being precipitated in situ to form a structure, imparting to the material a volume weight of from about 0.8 to about 1.2 g/cm.sup.3, the material being substantially free from carbon, hydrogen and available oxygen; process for the manufacture of such refractory lining.

Abstract: A ceramic material for a honeycomb structure is formed from a mixture of raw materials comprising, per 100 parts by weight of the mixture, 20 to 80 parts by weight of cordierite powder and 20 to 80 parts by weight of powder having a crystalline phase consisting mainly of a solid solution of SiO.sub.2 --Al.sub.2 O.sub.3 --Fe.sub.2 O.sub.3 --TiO.sub.2 --MgO. The mixture consists essentially of 15.7 to 44.0% by weight of SiO.sub.2, 29.8 to 41.0% by weight of Al.sub.2 O.sub.3, 0.9 to 8.3% by weight of Fe.sub.2 O.sub.3, 7.0 to 35.9% by weight of TiO.sub.2 and 4.9 to 16.1% by weight of MgO.

Abstract: A forsterite-carbon refractory containing forsterite material, carbonaceous material, silicon carbide and magnesia refractory material.

Abstract: A fused cast ceramic composition having superior corrosion and stoning resistance in the presence of E glass when compared with prior art compositions having comparable chromia content. The composition is a solidified fusion of from about 65 to about 98 weight percent Cr.sub.2 O.sub.3, from about 0.75 to about 4 weight percent MgO and from about 1 to about 34.25 weight percent alumina. The invention also comprises the method for manufacturing the composition by fusing the appropriate materials at the required concentrations.

Abstract: There is disclosed a green moulded product suitable for preparing shaped fired units comprising (a) at least 55% to 99% by weight of non-calcined asbestos tailings, the remainder comprising (b) at least one of (i) a heat decomposable metal salt selected from sodium, potassium, lithium, calcium, barium, magnesium, aluminum and mixtures thereof in an amount of from 1% to 15% by weight, (ii) a natural aluminum silicate in an amount of from 1% to 30% by weight, and (iii) mixtures of (i) and (ii). The properties of fired units are such that they can be used as structural bricks, medium refractory bricks, firebricks, tiles and the like.

Abstract: A calcined member for arc-extinguishing chambers which are installed in electromagnetic contactors and magnetic circuit breakers for high-voltage applications. The calcined member consists of an inorganic composite material obtained by molding and heat-treating a starting material under pressurized condition, the starting material comprising 10 to 50% by weight of a mica powder as a base material, 10 to 50% by weight of a magnesium oxide as a charging material, and 25 to 60% by weight of a mixture powder of boric acid, boric anhydride and zinc oxide as a binder.

Abstract: An energy-storage element, i.e. a body of high heat capacity capable of storing thermal energy and especially electrothermal energy, consists of 50-95% magnesium oxide, 5-50% iron oxide and a chemical binder, the mean particle size of the magnesium oxide lying between 0.1 and 4 mm and that of the iron oxide below 0.5 mm, preferably between 0.01 and 0.2 mm.

Abstract: An inorganic cement binder for a foundry aggregate comprising, in combination, potassium olivine phosphate and as a hardener therefor, water, aqueous sodium silicate, or aqueous phosphoric acid.

Abstract: An inorganic cement binder for a foundry aggregate comprising, in combination, potassium olivine phosphate and as a hardener therefor, water, aqueous sodium silicate, or aqueous phosphoric acid.

Abstract: To produce a dolomite sinter with a low porosity and a good hydration stability made of difficult-to-sinter raw dolomite, the dolomite is milled and caustic burnt dolomite, dolomite hydrate or semi-burnt dolomite in quantities between 3 and 20% by weight relative to the total mixture is added to the raw dolomite powder and is calculated as oxide, as well as foreign oxide, such as Fe.sub.2 O.sub.3, Al.sub.2 O.sub.3 or SiO.sub.2, in such quantities that the total content of the foreign oxide mixture is 1 to 3% by weight.

Abstract: A basic brick composition containing spinel clinker and magnesia clinker wherein pulverized iron oxide by additional weight mixing ratio is mixed or special magnesia clinker is substituted for magnesia clinker instead of addition of iron oxide.

Abstract: Provided by this invention is a slaking-resistant calcia refractory comprising, as a fired mixture, (a) 2% by weight or less of silicon dioxide, (b) aluminum oxide (Al.sub.2 O.sub.3) and magnesium oxide (MgO) of the amount defined in the graph of FIG. 5 as within the region enclosed by the lines connecting point A (2.5 wt % Al.sub.2 O.sub.3 and 0 wt % MgO), point B (1.5 wt % Al.sub.2 O.sub.3 and 1.5 wt % MgO), point C (1.5 wt % Al.sub.2 O.sub.3 and 8.5 wt % MgO) and point D (10 wt % Al.sub.2 O.sub.3 and 0 wt % MgO), (c) 0.9% by weight or less of iron oxide, and (d) a predominant amount of calcium oxide.

Abstract: A cast magnesium oxide based structure is utilized as a heat storage material. In preferred embodiments, the magnesium oxide heat storage material is cast directly about a source of heat. In another embodiment, a block of cast magnesium oxide based heat storage material is placed in contact with a source of heat forraising the temperature and storing heat and later moved to a different environment for transferring heat to that environment.

Abstract: There is disclosed a dry granular calcined magnetic fraction obtained from chrysotile asbestos tailings comprising as its main constituents from 25 to 43% MgO, from 25 to 43% SiO.sub.2, from 15 to 40% iron expressed as Fe.sub.2 O.sub.3, and an MgO/SiO.sub.2 ratio of from 0.8:1 to 1.3:1, said granular material passing a 4 mesh sieve. The novel product is useful for the preparation of heat storage cores and refractory bricks for glass tank checkers or blast furnace stoves.

Abstract: The invention relates to low-expansion ceramics, the chemical composition of which consists of 1.2 to 20% by weight of magnesia (MgO), 6.5 to 68% by weight of alumina (Al.sub.2 O.sub.3), 19 to 80% by weight of titanium in terms of titanium oxide (TiO.sub.2), 1 to 20% by weight of silica (SiO.sub.2), and 0.5 to 20% by weight of iron in terms of ferric oxide (Fe.sub.2 O.sub.3); the major component of crystalline phase thereof is a solid solution of magnesium oxide-aluminum oxide-titanium dioxide-silicon oxide-iron oxide; the ceramics have a coefficient of thermal expansion of not more than 20.times.10.sup.-7 (1/.degree.C.) in a temperature range of 25.degree. C. to 800.degree. C., a four-point flexural strength of not smaller than 50 kg/cm.sup.2 at room temperature, and a melting point of not lower than 1,500.degree. C.

Abstract: The present invention relates to low-expansion ceramics essentially consisting of 1.5 to 20% by weight of magnesia (MgO), 8 to 68% by weight of alumina (Al.sub.2 O.sub.3), 24 to 80% by weight of titanium in terms of titanium oxide (TiO.sub.2), and 0.5 to 20% by weight of iron in terms of ferric oxide (Fe.sub.2 O.sub.3), that major component of crystalline phase thereof is a solid solution of magnesium oxide-aluminum oxide-titanium dioxide-iron oxide, and that the ceramics has a coefficient of thermal expansion of not more than 20.times.10.sup.-7 (1/.degree. C.) in a temperature range of 25.degree. C. to 800.degree. C. and a melting point of not lower than 1,500.degree. C., said coefficient of thermal expansion being maintained even after exposure 1,100.degree. C. for 1,000 hours, and a method of producing low-expansion ceramics comprising steps of preparing a batch of compounds so as to provide a chemical composition of 1.5 to 20% by weight of magnesia (MgO), 8 to 68% by weight of alumina (Al.sub.2 O.sub.

Abstract: Impervious, unglazed, sintered ceramic products of primarily cordierite crystal phase, exhibiting low coefficients of thermal expansion and having analytical molar composition of about 1.7-2.4 RO . 1.9-2.4 Al.sub.2 O.sub.3 . 4.5-5.2 SiO.sub.2, are formed of mineral batch compositions that are: (a) wholly raw ceramic material wherein RO comprises about 55-95 mole % MnO and 5-45% MgO, or (b) at least about 50 wt.% prereacted cordierite material and the balance thereof raw ceramic material, and wherein RO comprises about 5-40 mole % MnO and 60-95 mole % MgO.

Abstract: Sprayable aqueous insulating liner compositions for metal casting vessels such as permanent refractory lined tundishes are disclosed that contain a water insoluble and hydration resistant particulate refractory grain containing MgO, organic binder and fibers, with the composition being substantially free of water soluble alkali and alkaline earth metal oxides that would migrate during drying with the water to degrade the permanent refractory lining.