Abstract: Ceramic beads having a bimodal pore distribution are prepared by a process involving a) formation of a ceramic particle slurry, b) adding a foamable prepolymer to the slurry to form a mixture, c) dispersing the mixture as beads in a second liquid, d) polymerizing and foaming the prepolymer, e) recovering the beads and firing them to remove the polymer and bond the ceramic particles. The beads can optionally be joined by sintering. Beads with a monodal pore distribution can be made by using a non-foaming prepolymer.

Abstract: Ceramic precursor materials bound together by a product of a condensation reaction between a first reactant that has at least one reactive hydroxyl moiety, such as a carbohydrate, and a second reactant that has at least one reactive nitrogen-containing moiety, such as melamine, and dried or dried and calcined, form porous aggregates that resist crushing or disintegration during processing through various reactor apparatus.

Abstract: A porous ceramic body of high structural strength and integrity is disclosed, along with the method of fabricating such, whereby a curable resin and a sinterable ceramic are mixed and then admixed to removable pore formers, then consolidated into a green body, the pore formers removed, and sintered into the porous ceramic body.

Abstract: A high temperature ceramic filter is produced from a composition containing refractory cement, aggregate, pore forming additives, and sintering agents. The pore forming additives are synthetic or organic powders or fibers which sublimate, melt, or otherwise disintegrate to produce In situ pores in the cement during the refractory treatment of a cast filter. The filters produced are permeable to high temperature gases commonly found in a coal furnace and can be used to collect particulate matter present in those gases.

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: A grinding tool is described which comprises self-bonded particles of a ceramic abrasive and has a voids volume of from 5 to 65%.

Abstract: A porous ceramic body of high structural strength and integrity is disclosed, along with the method of fabricating such, whereby a curable resin and a sinterable ceramic are mixed and then admixed to removable pore formers, then consolidated into a green body, the pore formers removed, and sintered into the porous ceramic body.

Abstract: A porous ceramic sinter and a process for producing the same are disclosed, which sinter has macropores with a pore size of from 20 to 2,000 .mu.m and three-dimensionally communicating pores that are made of interstices between secondary particles.

Abstract: There is herein disclosed a piezoelectric composite transducer comprising a plurality of piezoelectric ceramic poles. The plurality of piezoelectric ceramic poles are arranged two-dimensionally so as to form spaces therebetween. Organic films are disposed on both end surfaces of the plurality of piezoelectric ceramic poles so that the spaces forms hollow portions. The hollow portions causes making small its acoustic impedance up to a value close to the acoustic impedance of water or a human body.

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: A porous form body is produced of sinterable SiC-powder by forming a suitable suspension of said SiC-powder and then treating the suspension to convert it into droplets and the droplets into a granular material in which the granules are substantially larger than the particles of SiC-powder. The granular material is then formed into a green body, e.g. by spraying the granules onto a negative mold of the form body or slip-casting or the like. The green body is then sintered whereby the resulting porosity in the final form body provides the form body with low drag.

Abstract: Cellular glass structures are made by foaming select silicone resins. A foaming agent is reacted together with the silicone resin to form a foam that carries the resin as a continuous separate phase distributed throughout the foam. The foaming agent is removed by decomposition, and the remaining silicone resin is crosslinked to retain the foamed structure. The silicone resin is then heated in a non-oxidizing atmosphere at a temperature that will pyrolize the resin. During pyrolysis, the resin densifies to foam a unique glass composition comprised of silicon, oxygen and carbon, where carbon is chemically bonded to silicon, but there are essentially no chemical bonds between carbon and oxygen.

Abstract: A porous cordierite ceramic and a process for making the same are provided by the present invention. Preferably, the ceramic material includes at least about 95 percent cordierite in the crystal phase, a porosity of at least about 30 volume percent, a crush load strength of at least about 6 pounds, and a thermal conductivity of less than about 5 watts/meter-.degree.K. The method of producing a porous cordierite ceramic includes (a) combining alumina, clay, talc, a pore-forming material and preferably free silica; (b) adding binder, water and other additives; and (c) shaping the mixture to form a green body. The green body is thereafter fired to form a sintered ceramic body. The porous cordierite is useful in a heat source retainer.

Abstract: Porous ceramic greenware comprising finely divided ceramic filler, finely divided metal, and polyolefin controls shrinkage in fired shape. In a preferred embodiment the metal and ceramic filler are bound together with the clean burning polyolefin and a plasticizer. After molding the mixture into the final shape, the plasticizer is removed to introduce porosity into the shaped article. Next the article is heated to decompose the polyolefin which can exit as a gas through the pore openings. Finally, the article is fired to a high temperature to oxidize the metal to metal oxide which becomes sintered with the ceramic filler particles to form a sintered porous article where the oxidized metal bonds the filler particles together in the desired shape.

Abstract: A process for the preparation of a micro-cellular porous ceramic body is disclosed, in which an .alpha.-olefin oligomer is added as a molding assistant to an ultrafine ceramic powder in an amount of 65 to 330% by weight based on the ultrafine ceramic powder, the mixture is kneaded, the kneaded mixture is compression-molded to give a molded body, and the molded body is fired.

Abstract: Porous green ceramic parts may be prepared by componding 90 to 60 weight percent of a particulate ceramic material with 10 to 40 weight percent, on a dry basis, of a latex of a polymer. The compound is frothed, shaped and set. The green part may then be sintered. The process avoids the expense of preparing solid ceramic compounds containing waxes or sawdust which burn out to create voids. The process is useful to prepare ceramic filters, catalysts, or light weight metal ceramic foams.

Abstract: A ceramic aggregate for concrete is made from a mixture of clay and dried organic garbage in a ratio of about three parts by volume of organic garbage to about one part by volume clay. The mixture is shaped into pancake-shaped pellets and fired at a temperature in excess of the vitrification point of the clay to cause the surface of the pellets to melt and harden the pellets.

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 one 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: The inventive prosthetic body for bone substitute is a sintered body of hydroxyapatite and characterized by the open pore structure with a pore diameter in a specified range forming a porosity of 20 to 40% and a bending strength of at least 100 kg/cm.sup.2. The sintered body can be prepared by blending powders of hydroxyapatite and a thermally decomposable substance, e.g. crystalline cellulose, each having a specified particle size distribution, in a specified proportion and shaping and sintering the powder blend.

Abstract: A fluid-permeable article which permits fluid to pass therethrough includes a porous ceramic structure having a multiplicity of hollow members made of ceramic material which are concatenated with each other to form a framework having a continuous capillary passageway system. A continuous space is formed outside of the framework and is defined by the outer surfaces of the hollow members. A continuous matrix material fills the continuous space outside of the framework and cooperates with the porous ceramic structure to provide an integral composite structure consisting of the ceramic material and the matrix material. The continuous passageway system is open in at least a portion of the exposed surfaces of the article and permits fluids to pass therethrough.

Abstract: A process for preparing ceramic moldings containing no organic matter with retention of their original shapes which comprises mixing 100 parts by weight of ceramic powders and/or fibers, 0.1 to 50 parts by weight of papermaking organic fibers and/or wet-end additives and 3 to 200 parts by weight of mountain leather, molding the resulting mixture to obtain an unburned molding having enough mechanical strength to withstand molding processings and, subjecting the unburned molding to burning treatment.

Abstract: A ceramic composition to make cement with insulating properties is a mixture of cement, ceramic grog and ceramic aggregate beads, the ceramic grog and aggregate being a mixture of clay and dried organic mulch. After firing, the resulting ceramic product is porous. When added to the cement, the porous ceramic grog and aggregate greatly enhance the insulation qualities of the resultant cement structure. The dried organic mulch is formed from pellets produced from commercially reclaimed garbage.

Abstract: A process for producing porous ceramics with controlled microstructure. Colloidal suspensions of polymeric microspheres of a selected size and shape, and aluminum oxide particles are consolidated to form a compact. The compact is heated to decompose the microspheres to leave pores, and to sinter the compact, to form a porous ceramic body with a plurality of pores preferably substantially the same size and shape, where the pores are substantially spherical and are evenly distributed and noncontiguous throughout the ceramic matrix and with strength comparable to its dense state.

Abstract: The use of pectins (or pectin-like materials) as an additive to clay to provide clay compositions of enhanced plasticity and stability is disclosed.

Abstract: A microporous separating material is produced by a method which comprises preparing a mixture of (1) macromolecular quaternary ammonium salt having a quaternary amine linked to a water-soluble macromolecular compound and possessing basicity, (2) a polymer of a polyoxyethylene alkylvinyl monomer and a vinyl monomer possessing basicity, or (3) a polymer of a halogenide of a quaternary amine, i.e. a basic macromolecular compound, and at least one water-soluble macromolecular substance selected from the group consisting of cellulose, polyvinyl alcohol, polyethylene oxide, and polyacrylamide with a smectite type mineral, mixing the aforementioned mixture with an inorganic substance in a water-soluble state, drying the resulting mixture, and firing the dried mixture.

Abstract: A piezoelectric ceramic powder is, together with a binder, processed to a granulate. This granulate is mixed with a pearl polymer to a mixture. The mixture is pressed to a suitable shape, and then in a first firing step the binder and the pearl polymer are fired out. Preferably the first firing process is followed by a second firing step for sintering. Thereafter mechanical fabrication may take place, to give the end product its shape. The firing out of the pearl polymer results in a porous piezoelectric ceramic, with which, when used in an ultrasonic transducer, a high transducer effectiveness, sharp ultrasonic pulses with little edge radiation as well as a good electric and acoustic adaptation can be achieved.

Abstract: The present invention relates to materials and more particularly to composite materials in which a selected substance is supported by a support material.A composite material in accordance with the present invention comprises porous hollow particles of an inorganic material in which there is supported a selected substance (such as chromagraphic organic gel, or a liquid for use in two-phase separation processes).The porous hollow particles may be formed from, for example, a material such as kieselguhr and/or an inorganic oxide.The porous hollow particles may be formed by coating a fugitive core material (e.g. organic beads) with inorganic material and heating to remove the fugitive core material.

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: Non-oxide refractory foams, possessing controlled permeability and uniformity, are prepared by impregnating an organic polymer foam material with a fluid, particulate slurry of a first refractory material, drying, applying to the dried, impregnated material a second refractory material which has a lower melting point than the first refractory material and thereafter heating, at a temperature sufficient to cause melt infiltration of the second refractory material into the impregnated material, thus producing inert and dimensionally stable composite refractory foams having broad utility as particulate filters or carriers.

Abstract: Monolithic refractories containing refractory aggregate, cement and a hydrocolloid.

Abstract: An aqueous preparations of a gel-like consistency, containing(A) 1-15% by weight of hydrophilic polyurethanes,(B) optionally up to 3% by weight of hydrophilic polymers which are water-soluble or capable of swelling in water, based on unsaturated monomers and/or modified cellulose derivatives,(C) optionally up to 2% by weight of surface active agents,(D) optionally up to 30% by weight of powder, and(E) 0.3-30% by weight of oil.The aqueous preparation is useful as a porosifying agent in the production of porous ceramic bodies.

Abstract: An aqueous preparations of a gel-like consistency, containing(a) oils in quantities of from 0.03 to 30% by weight,(b) water-soluble or swellable vinyl polymers in quantities of from 0.2 to 10% by weight,(c) water-soluble or swellable polymers based on natural substances in quantities of from 0.01 to 5% by weight,(d) surfactants in quantities of from 0.01 to 2% by weight and optionally(e) inorganic or organic powders in quantities of from 0.5 to 30% by weight.The aqueous preparation is useful as a porosifying agent in the production of porous ceramic bodies.

Abstract: Monolithic refractories comprising non-basic refractory aggregates, a binder, and vinyl chloride acetate.

Abstract: A novel low density molded porous sintered body contains at least 90% open pores having a specific diameter distributed equally in all directions. The material of the molded body is preferably a vitreous and/or crystalline and/or ceramic substance having a low thermal coefficient of expansion.

Abstract: Ceramic fiber is co-dispersed in a liquid medium together with a heat curable organic binder, and the mixture is beaten preferably with small amounts of a crystallizable salt and fillers. Upon beating, the mixture is foamed, and the foam is then heated to cure the binder, evaporate the liquid, and stabilize the foam. The foam may be used as is, but is preferably further heated to decompose most of the organic binder and to cause bonding between intersecting fibers by the salt, thereby resulting in a stable foam that has excellent high temperature properties.

Abstract: A thermal insulation material at high temperature comprising insulating mineral fibres bonded in a matrix, wherein the mineral fibres have a melting point higher than 1.000.degree. C. and represent 15 to 60% of the weight of the material, and wherein the matrix is formed, at least in part, by pyrolytic carbon which represents 18 to 40% of the weight of the material. A method for making such a material comprises dispersing a carbon-containing material such as a resin made of fibrous reinforcement, shaping by moulding the mixture thus obtained and pyrolysis of the carbon-containing material.