Abstract: A soluble thermally cellulated, ceramic mold member, having gas evolved cells dispersed in a soluble crystalline matrix, the matrix consisting predominantly of at least one crystal phase selected from the group consisting of borates and phosphates of alkali metals, of divalent metals and of aluminum, and boron phosphate, and having at least one solubilizing agent selected from alkali metal compounds, divalent metal compounds and charred acrylic resin. A mixture capable of being thermally foamed to a cellulated body, the mixture consisting essentially of at least one phosphorous-containing compound, at least one boron-containing compound, at least one solubilizing agent selected from the group consisting of alkali metal compounds, divalent metal compounds and acrylic resins, at least one organic binder and a gas-evolving agent.

Abstract: This invention relates to a foamable silicate composition comprising (a) one or more alkali metal silicates, (b) a blowing agent, (c) a hardener which can be an acetate or a formate ester of a di-polyhydric alcohol or a polyoxyalkylene glycol and (d) a surfactant having a hydrophilic-lypophilic balance of at least 8. The formulations are readily produced by mixing the components, are pourable, pumpable and sprayable, and give rise to foams of excellent compressive strength and thermal insulation properties under ambient conditions.

Abstract: There is provided a thermal shock-resistant silicon nitride sintered material including silicon nitride and rare earth element compounds, which material contains at least 10 pore groups per mm.sup.2, each pore group consisting of pores of 10 or less in diameter and which material has a thermal shock resistance .DELTA.Tc (.degree.C.) of 1,000.degree. C. or more. The thermal shock-resistant silicon nitride sintered material can be produced by mixing and shaping starting materials consisting of silicon nitride powders of rare earth element oxides and carbide powder, and then firing the shaped material in a nitrogen atmosphere to decompose the carbide powders.

Abstract: The invention relates to a process and an apparatus for converting metal nitrate or mixed metal nitrate solutions into the corresponding metal oxides in a microwave field. The invention consists in heating, while the feed stream is being metered in, in such a manner that the solvent always evaporates within seconds and the decomposition product is obtained as a porous, sponge-like, purely oxidic material, which can be ground easily to give a powder having particle sizes of 0.5 to about 10 .mu.m. The controlled metering in of the nitrate solution simultaneously makes it possible to control the reaction temperature below the sintering temperature of the powder. The reaction of the nitrate starting solution can take place continuously/batchwise in a reaction flask or continuously in a rotating reaction pipe, which is preferably charged with grinding balls, which possibly exert a reaction-activating effect similar to that exerted very particularly by the metal oxide sponge formed during the reaction.

Abstract: A high density, shock resistant ceramic comprising from 1 to about 4 mols of a a dense spinel ceramic matrix having dispersed therein, 1.5 to 1, respectively, of a metal oxide derived from a decomposable salt of said metal and having a thermal expansion characteristic different from said dense spinel ceramic matrix and at the decomposition temperature a volume less than that exhibited by its salt form and a process for preparing same.

Abstract: Green ceramic formulations comprising a polyisobutylene binder are suitable for tape casting and can be effectively removed during thermal processing in reducing atmospheres. The binder may be removed in substantially dry reducing atmosphere. The tapes may be used for forming ceramic substrates and metallized ceramics such as those used in electronic packaging.

Abstract: A method of manufacturing a molten metal-resisting ceramic fiber composition includes mixing ceramic fibers, a frit, ceramic additives, a low temperature binder, and water. The mixture is formed into a desired shape, preferably by being extruded through a die. The shaped mixture is baked at low temperature, and then is fired at high temperature. During firing, the low temperature binder is oxidized and the frit is melted so as to substantially coat the fibers and fuse them into a porous matrix.

Abstract: Ceramic foams in which the open cells are connected by a three-dimensional, substantially continuous ceramic matrix formed of interconnected hollow ligaments, are made from an open-cell, reticulated precursor metal, i.e. a metal foam. The precursor metal first is treated so as to allow a support coating to form thereon, and thereafter the coated precursor is heated above the melting point of the metal in the presence of an oxidant to form an oxidation reaction product.

Abstract: There is provided a thermal shock-resistant silicon nitride sintered material consisting substantially of silicon nitride and rare earth element compounds, which material contains at least 10 pore groups per mm.sup.2, each pore group consisting of pores of 10 .mu.m or less and which material has a thermal shock resistance .DELTA.Tc (.degree.C.) of 1,000 .degree. C. or more. The thermal shock-resistant silicon nitride sintered material can be produced by mixing and shaping starting materials consisting of a silicon nitride powders of rare earth element oxides and carbide power, and then firing the shaped material in a nitrogen atmosphere to decompose the carbide powders.

Abstract: Discrete, free-flowing, ceramic microbubbles consist essentially of at least one of a non-oxide component and an oxide component having diameters in the range of 1 to 300 micrometers and each having a wall thickness of less than 10 percent of the diameter of the bubble. In the process of the invention, a sol precursor and a suitable liquid, referred to as a bloating agent, when added to a bubble promoting medium under proper conditions, provide green gelled microbubbles which after firing are ceramic microbubbles having wall thicknesses less than 10 percent of the diameter of the bubbles. The microbubbles are non-vitreous, sol-gel derived, fine microstructured, uniform, hollow, smooth, and are either essentially all oxide or non-oxide or combinations of both.

Abstract: Ceramic foams in which the open cells are connected by a three-dimensional, substantially continuous ceramic matrix formed of interconnected hollow ligaments, are made from an open-cell, reticulated precursor metal, i.e., a metal foam. The precursor metal first is treated so as to allow a support coating to form thereon, and thereafter the coated precursor is heated above the melting point of the metal in the presence of an oxidant to form an oxidation reaction product.

Abstract: Ceramic bodies suitable for use in the filtration of molten metal are formed by immersing a porous organic substrate material in an aqueous thixotropic slurry containing yttria, zirconia and alumina; expelling excess slurry; drying the impregnated material; and heating to an elevated temperature to burn off the organic material and sinter the ceramic materials. The resulting zirconia-alumina ceramic bodies have from about 5-80% of the zirconia in a monoclinic phase and the remainder of the zirconia essentially in a stabilized cubic phase due to the yttria. The ceramic bodies thus produced have excellent strength, density, and thermal shock resistance properties.

Abstract: The present invention relates to a ceramic foam material, preferably a ceramic foam filter, prepared by providing an open cell flexible foam having a plurality of interconnected voids surrounded by a web of the flexible foam, applying an adhesion promoting material to at least one surface of the flexible foam, impregnating the flexible foam after applying the adhesion promoting material with a ceramic slurry, drying and heating the impregnated material to remove the organic component therefrom, and firing at an elevated temperature to form the filter. In a preferred embodiment, a flocked coating is formed on at least on surface of the flexible foam prior to impregnation. The flocked coating may be formed either by first applying a solution containing an adhesive to the surface(s) and thereafter applying fibers to the surface or by applying a solution containing the adhesive and the fibers.

Abstract: Ultra-fine hollow glass spheres suitable as a filler in light-weight composite materials for building use and the like can be prepared from a fine powder of volcanic glass even when the starting powder has a particle size as fine as 20 .mu.m or smaller. The inventive method comprises an acid-leaching treatment of the starting powder using hydrochloric or sulfuric acid under hydrothermal conditions at 150.degree.-200.degree. C. to modify the chemical composition in the surface layer of the particles and a subsequent heat treatment of the acid-treated particles at a specified high temperature to effect expansion by the water vapor produced from the structural water in the softened particles. By virtue of the modified composition in the surface layer and in contrast to the prior art method without the acid treatment, a good balance can be obtained between the rate of water vapor release and softening of the particles even when the particle size is extremely small to facilitate expansion of the particles.

Abstract: This invention relates to a rigid, water-resistant phosphate ceramic product having improved acoustical properties; the components used to prepare the product; and its process of manufacture.

Abstract: The invention relates to a method of manufacturing permeable mineral membranes.The method of the invention is characterized in that a thin layer of gel of peptised hydroxide of at least aluminum is deposited on a permeable perous substrate and the resulting membrane is dried and fired at a temperature between 500.degree. and 1100.degree. C.The resulting membranes can be used for isotopic separation of gases or for filtration and ultrafiltration.

Abstract: A material having superior that insulating qualities which may be formed in flat sheets or any other desired configuration. The material in its basic form is produced by mixing an alkali metal halide or nitrate into an alkali metal silicate solution to form a polymerized silicate gel. The gel may be heated to cause intumescence and the formation of a dry cellular ceramic, or may be used in gel form, e.g., as a fireproof barrier which will expand upon exposure to heat. Physical properties of the end product are altered by the inclusion of one or more additives prior to the polymerization reaction. These additives may be any of a number of materials that do not significantly react with the alkali metal silicate solution or otherwise inhibit the formation of the gel.

Abstract: A method of manufacturing a molten metal-resisting ceramic fiber composition includes mixing ceramic fibers, a frit, ceramic additives, a low temperature binder, and water. The mixture is formed into a desired shape, preferably by being extruded through a die. The shaped mixture is baked at low temperature, and then is fired at high temperature. During firing, the low temperature binder is oxidized and the frit is melted so as to substantially coat the fibers and fuse them into a porous matrix.

Abstract: A high density, shock resistant ceramic comprising from 1 to about 4 mols of a dense spinel ceramic matrix having dispersed therein, 1.5 to 1, respectively, of a metal oxide derived from a decomposable salt of said metal and having a thermal expansion characteristic different from said dense spinel ceramic matrix and at the decomposition temperature a volume less than that exhibited by its salt form and a process for preparing same.

Abstract: In accordance with the invention, a composition of matter is provided for forming a coating for protecting carbonaceous substrates from degradation at elevated temperatures. The composition of matter is a mixture of particulate silicon, silicon carbide and alumina. The mixture contains between about 40% and 50% silicon by weight of the total composition, between about 30% and 50% silicon carbide by weight of the total composition and between about 20% and 30% alumina by weight of the total composition. A method is provided for forming a primary protective coating on carbonaceous substrates utilizing the aforesaid mixture. An enhancement coating is provided for sealing the primary coating in applications where the substrate will be subjected to elevated temperatures and temperature cycling.

Abstract: A composition and process for producing a foamed glass molded product, the process employing a composition which is a mixture of one part by weight of a finely ground glass containing more than 25 weight % alkali metal oxide; from 21 to 400 parts by weight of a finely ground glass containing less than 16 weight % alkali metal oxide; water present in a water to solids weight ratio ranging from 1:1.4 to 1:3.0; and a foaming agent. The combined ingredients are heated to release gasses from the foaming agent and thereby foam the glass. The foamed glass moldings may be granules or cast shapes.

Abstract: A thermal insulating material of an expanded, shell-less silica-hydrate has a small bubble structure to enhance the thermal insulating characteristics of the material. Also described is a process for the production of the expanded, shell-less silica-hydrate through selective heating of the silica-hydrate in a moist environment.

Abstract: The present invention relates to a novel crystalline massive aluminosilicate with an expanded structure and to its process of manufacture. The particular structure is a closed cell structure containing nitrogen. It is obtained by: grinding industrial glass; adding aluminum based nitride in the proportion of 0.1 to 20% by weight with respect to the weight of the ground industrial glass; mixing the ground glass and so-added nitride; oxidizing the nitride within said mixture by heating to a temperature of 800.degree. to 1000.degree. C. for about 1 hour, and cooling and recovering the expanded crystalline aluminosilicate. The material has multiple applications in the building industry and in the construction of furnaces, in the manufacture of fireproof walls and doors, and in naval construction, with various advantages over prior art materials.

Abstract: New type porous cordierite ceramics having a new characteristic interconnecting open cellular structure and a hollow microspherical cordierite glass powder with a shell devoid of any pores or provided with a few or an abundance of open pores which is used as a starting material for the porous cordierite ceramics. The porous cordierite ceramics are produced by subjecting a starting solution containing an alkyl silicate, an aluminum salt and an magnesium salt optionally with other compounds in an organic or aqueous organic solvent to spray thermal decomposition to prepare the hollow microspherical cordierite glass powder, and then processing the cordierite glass powder to a shaped body after or before an optional heat treatment and firing the shaped body at a temperature below the melting point of cordierite. The porous cordierite ceramics are useful as a carrier for gas chromatography or various chemical reactions.

Abstract: A porous ceramic material composed of a sintered porous body of a calcium phosphate compound is described. A multiplicity of capillary void paths having a diameter of 1 to 30 .mu.m and a multiplicity of pores having a diameter of 1 to 600 .mu.m are formed in the sintered porous body. At least part of the pores are connected to the exterior space of the sintered porous body through at least a part of the capillary voids. The porous ceramic material is valuable as a medical material, e.g., a substitute or prosthesis for bone or dental root, and also an electronic material and a genetic engineering material.When the porous ceramic material is embedded in a bone defect of human or animals, osteolytic cells, osteoblasts, erythrocytes and body fluid are selectively allowed to intrude through the porous ceramic material while almost no intrusion of osteoclasts and collagen fibers is allowed.

Abstract: Immiscible components are controllably released into aqueous systems by impregnating silica-silicate open cell foams with the immiscible components. As the silica-silicate foams are gradually dissolved, the immiscible components are released. Fragrance oils and dyes are particularly adaptable for use in the invention. In fact, silica-silicate foams impregnated with fragrance oils having polar functional groups, exhibit an unexpectedly slower rate of dissolution into aqueous environments and consequently, fragrance oils and dyes admixed therewith are released in aqueous systems over extended time periods.

Abstract: Disclosed is a lightweight silicate aggregate produced by the steps of mixing together dry rice hull ash, an alkali metal hydroxide, boric acid, and water; heating the mixture to a temperature sufficient to initiate reaction; curing the composition at a temperature less than the boiling point of water until the reaction is complete; comminuting the cured product and heating the comminuted product to form the expanded aggregate. The expanded aggregate is useful as, inter alia, a sorbent, filler, energy insulator or filter.

Abstract: Hollow, fine-grained ceramic proppants are less expensive and improve fracture control when compared to conventional proppants (dense alumina, mullite, bauxite, zirconia, etc.). Hollow proppants of the present invention have been fabricated by spray drying, followed by sintering in order to obtain a dense case and a hollow core. These proppants generally have high sphericity and roundness (Krumbein sphericity and roundness greater than 0.8), have diameters on average between 2250 and 125 .mu.m, depending on proppant size required, and have strength equal to or greater than that of sand. The hollow core, the size of which can be controlled, permits better fracture control in hydraulic fracturing treatments since the proppant can be transported in lower viscosity fluids. Hollow proppants produced at the same cost/weight as conventional proppants also provide for lower costs, since less weight is required to fill the same volume. The fine-grained (preferably less than 5 .mu.

Abstract: Strong rigid foams comprising one or more layer minerals useful as insulation and fire-protection materials contain cells of which the mean diameter is below 60 microns, 90% have a diameter below 100 microns and substantially all are of diameter below 150 microns and are made by gasifying an aqueous suspension of the layer mineral(s) to produce a wet foam or froth containing bubbles of gas of which the diameters are as stated above and removing water from the wet foam or froth.

Abstract: A method for producing a high porosity ceramic material characterized by the steps of: (1) wetting a finely divided, non-crystalline, amorphous silica with a wetting agent; (2) combining the wetted silica with a ceramic slip to produce a mixture; and (3) removing the majority of the wetting agent to produce a solid, low-density, highly porous bisque. The bisque if preferably partially covered with an impermeable coating, and an aromatic fluid is applied to an exposed surface of the bisque for absorption into the body of the bisque.

Abstract: Method for making shaped foam glass bodies from ground glass by hydrolysis in a hydrolysis mixture with solid alkali silicate and water, in which at least one foaming agent is added to the hydrolysis mixture, or to a resulting slip to form a foam producing mass, and in which the foam producing mass is foamed at an increased temperature. A mixture of two types of glass, namely (a) glass containing more than 16% by weight alkali oxide, and (b) glass containing less than 16% by weight alkali oxide, 95% of each having a grain size of less than 0.1 mm, at a weight ratio of a:b=1.1.5 to 1:20 is mixed with water at temperatures from 50.degree. to 100.degree. C. until the mixture thickens, the ratio of water to total solids being 1:1.4 to 2.5. The resulting mass into shaped foam glass bodies.

Abstract: The disclosure describes ceramic foams, for example made of clay, and a process for preparing these foams. Once there is obtained a mixture defining a slip, the latter is caused to be foamed by the addition of controlled quantities of a gas, such as air, thus making it possible to reproduce foams having predetermined physical properties. It is preferable to dry the foam under conditions where the temperature is heterogeneous and in the absence of ventilation. This operation can be carried out by placing the foam under heating elements at a temperature between 30.degree. C. at the start to 100.degree. C. towards the end of the drying, while practically preventing any ventilation in the vicinity of the foam. This process is mainly advantageous in that it enables one to control the physical properties of the foam obtained thereby. This foam can be used as an industrial absorbent, acoustical insulating material, fire-wall, thermal insulating material, etc. by varying the density of the foam.

Abstract: Silicate-based composition particles are rapidly and completely expanded to form an expanded, cellular particulate aggregate of maximum density in short periods of time at particle temperatures which are comparatively low, that is, 100.degree. C., compared to existing systems by the utilization of infrared heat sources, either gas or electric, to heat the silicate particles. The use of infrared energy operates in a surprisingly advantageous fashion when the expansion process is carried out on or in the presence of a surface having the capacity to act as a thermal mirror or absorber-reflector of the infrared radiation to make maximum utilization of the radiant energy by the creation of a radiation trap. Carbonaceous materials are preferred for producing such entrapment. A further significant aspect is the discovery of a time-radiation dependency.

Abstract: A rigid inorganic foam of cellular structure comprising one or more layer minerals, and a method for making inorganic foams comprising gasifying a suspension of one or more layer minerals in a liquid medium, shaping the gasified suspension, and removing the liquid medium from the shaped gasified suspension.

Abstract: The present invention concerns rigid, water-resistant phosphate ceramic materials which may be prepared from components comprising metal oxide, calcium silicate, and phosphoric acid. By prereacting a portion of the metal oxide with the phosphoric acid and/or by adjusting the temperature of the acid solution when it is combined with the other ingredients, the character of the resulting product can be controlled to give foamed or unfoamed phosphate ceramic material.

Abstract: An unfired foamed-in-place two component insulating refractory and the method for preparing the same. The composition is composed of hydraulic cement, water and an acid, though it can also include an aggregate and/or fine grain inert filler. In the process, the dry ingredients are mixed with the water to form a slurry and thereafter the acid is added to the slurry and passed through a passive mixer before the acid-slurry mixture is discharged and allowed to foam and set.

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 present invention concerns rigid, water-resistant phosphate ceramic materials which may be prepared from components comprising metal oxide, calcium silicate, and phosphoric acid. By prereacting a portion of the metal oxide with the phosphoric acid and/or by adjusting the temperature of the acid solution when it is combined with the other ingredients, the character of the resulting product can be controlled to give foamed or unfoamed phosphate ceramic material.