Abstract: A method for making a dental restoration by milling a dental model from a partially sintered ceramic material, applying dental material thereon, and curing the dental material on the model to obtain a dental restoration. The method can be used for forming a variety of dental restorations including, but not limited to, crowns, bridges, space maintainers, tooth replacement appliances, orthodontic retainers, dentures, posts, jackets, inlays, onlays, facings, veneers, facets, implants, abutments, splints, partial crowns, teeth, cylinders, pins, and connectors.

Abstract: Fully dense, diamond-silicon carbide composites are prepared from ball-milled microcrystalline diamond/amorphous silicon powder mixture. The ball-milled powder is sintered (P=5-8 GPa, T=1400K-2300K) to form composites having high fracture toughness. A composite made at 5 GPa/1673K had a measured fracture toughness of 12 MPa·m1/2. By contrast, liquid infiltration of silicon into diamond powder at 5 GPa/1673K produces a composite with higher hardness but lower fracture toughness. X-ray diffraction patterns and Raman spectra indicate that amorphous silicon is partially transformed into nanocrystalline silicon at 5 GPa/873K, and nanocrystalline silicon carbide forms at higher temperatures.

Abstract: A method for producing high-alumina bodies with superior chemical properties at reduced sintering temperatures, including the steps of providing an alumina powder precursor, adding about 4 weight percent magnesia powder precursor, homogenizing the resultant green powder precursor, pressing a green body from the green powder precursor, removing residual moisture and organic material from the green body, and firing the green body to about cone 13, wherein the resulting high-alumina body is substantially non-vitreous, has a substantially uniformly sized grain structure, is very resistant to dissolution in molten aluminum, and has superior resistance to chemical attack over substantially the entire pH range.

Abstract: A method to make thick or thin films a very low cost. The method is generally similar to the conventional tape casting techniques while being more flexible and versatile. The invention involves preparing a slip (solution) of desired material and including solvents such as ethanol and an appropriate dispersant to prevent agglomeration. The slip is then sprayed on a substrate to be coated using an atomizer which spreads the slip in a fine mist. Upon hitting the substrate, the solvent evaporates, leaving a green tape containing the powder and other additives, whereafter the tape may be punctured, cut, and heated for the desired application. The tape thickness can vary from about 1 &mgr;m upward.

Abstract: A process for producing a carbon fiber sheet, which comprises allowing, as necessary, an oxidized polyacrylonitrile fiber sheet to contain 0.2 to 5% by mass of a resin, then subjecting the resin-containing oxidized polyacrylonitrile fiber sheet to a compression treatment in the thickness direction under the conditions of 150 to 300° C. and 5 to 100 MPa (10 to 100 MPa when no resin treatment is made) to obtain a compressed, oxidized fiber sheet having a bulk density of 0.40 to 0.80 g/cm3 and a compression ratio of 40 to 75%, and thereafter subjecting the compressed, oxidized fiber sheet to a carbonizing treatment, which carbon fiber sheet has a thickness of 0.15 to 1.0 mm, a bulk density of 0.15 to 0.45 g/cm3, a carbon fiber content of 95% by mass or more, a compression deformation ratio of 10 to 35%, an electric resistance of 6 m&OHgr; or less and a feeling of 5 to 70 g.

Abstract: Unfired first ceramic layers 11 and at least one unfired second ceramic layer 12 having a different color from the unfired first ceramic layers 11 are laminated to prepare an unfired ceramic laminate 13. Notches 14 are then formed on a surface of the unfired ceramic laminate 13 using the second ceramic layer 12 as a reference. The unfired ceramic laminate 13 is fired to provide a fired ceramic laminate 13a, which is then divided along the notches 14 into ceramic composites 13b. In this process, notches having the proper depth can be formed on the unfired ceramic laminate 13.

Abstract: A process for making an alkaline resistant material comprises the steps of grinding together 0-40% light magnesia, 0-80% roasted magnesia, 10-54% ceramic clay, 0-9% limestone, 1-4% water glass, 0-1.5% carboxymethyl cellusolve, 0-27% talc, 0-3% calcium or barium carbonate to a particle size of less than 50 microns, mixing the ground mixture with water to produce a paste containing <23% wt. water, shaping the paste to a desired shape, drying the shaped product at a temperature of 110 degrees Centigrade, and firing the dried shaped product in a kiln at 1350 degrees Centigrade. The resulting alkali resistant ceramic contains 25-76 wt % MgO, 13-47% SiO2, 5-20 wt % Al2O3, and 1-10 wt % Fe2O3, CaO, K2O, and/or Na2O, with forsterite and spinel being the dominant crystalline phases.

Abstract: Method for forming large-dimension ceramic tiles comprising the following operative stages: feeding a determined quantity of powders into the mould cavity of a first pressing station; pressing said quantity of powders to obtain a slab of congruent material the thickness of which is reduced by a quantity between 20 and 40%; feeding said slab to at least one decorating station which deposits in a controlled manner at least a second layer of powders; feeding said decorated slab to a second pressing station; pressing the decorated slab.

Abstract: A sputtering target is provided that includes SiC and metallic Si and has an atomic ratio of C to Si of from 0.5 to 0.95 and a density of from 2.75×103 kg/m3 to 3.1×103 kg/m3. The sputtering target is capable of forming at high speed a film that contains SiO2 as the main component and has a low refractive index. The sputtering target can be produced by a process in which a molded product of SiC is impregnated with molten Si.

Abstract: A description is given of a filling level measuring device operating with microwaves, having a housing and an insert composed of a dielectric, and of a process for producing the dielectric, in which the dielectric constant of the insert is adjustable and in which the insert has a high chemical resistance and a mechanical strength adequate for industrial applications. The dielectric is a composite material composed of a fluoroplastic, in particular polytetrafluoroethylene, and ceramic and is produced by mixing powdered ceramic and powdered fluoroplastic, drying the mixture, pressing the mixture and sintering the pressed mixture.

Abstract: Processes for mechanically fabricating two and three-dimensional fibrous monolith composites include preparing a fibrous monolith filament from a core composition of a first powder material and a boundary material of a second powder material. The filament includes a first portion of the core composition surrounded by a second portion of the boundary composition. One or more filaments are extruded through a mechanically-controlled deposition nozzle onto a working surface to create a fibrous monolith composite object. The objects may be formed directly from computer models and have complex geometries.

Abstract: The core/jacket catalyst molding with a core made from an inorganic support material and with a jacket made from a catalytically active material can be prepared by coextruding an aqueous molding composition which comprises the support material or a precursor thereof, with an aqueous molding composition which comprises the catalytically active material or a precursor thereof, then drying the coextrudate, and then calcining the dried coextrudate.

Abstract: A process of making an electrochemical device comprising providing a trilayer structure comprising an electrode/electrolyte/electrode and simultaneously sintering the trilayer structure.

Abstract: A method of making an EUV lithography stage structure includes depositing a layer of a Ti doped SiO2 glass powder in a confined region to provide an underlying layer; applying a binder to form a primitive with the binder bonding the glass powder together at one or more selected regions; depositing an above layer of the glass powder above the deposited layer; applying the binder to the above layer with the binder bonding the glass powder together at one or more selected regions; repeating the deposition and binding steps to produce a number of successive layers with the binder bonding the successive layers together; and removing the unbonded glass powder to provide a bonded glass powder lithography stage structure which is then sintered and densified into a densified nonpowder glass lithography stage.

Abstract: A method for reaction forming refractory metal carbides. The method involves the fabrication of a glassy carbon preform by casting an organic, resin-based liquid mixture into a mold and subsequently heat treating it in two steps, which cures and pyrolizes the resin resulting in a porous carbon preform. By varying the amounts of the constituents in the organic, resin-based liquid mixture, control over the density of the carbon preform is obtained. Control of the density and microstructure of the carbon preform allows for determination of the microstructure and properties of the refractory metal carbide material produced. The glassy carbon preform is placed on a bed of refractory metal or refractory metal—silicon alloy. The pieces are heated above the melting point of the metal or alloy. The molten metal wicks inside the porous carbon preform and reacts, forming the refractory metal carbide or refractory metal carbide plus a minor secondary phase.

Abstract: A multilayer ceramic composite is described which contains at least one supporting zone having oxidation-sensitive reinforcing fibers as well as a matrix. The matrix optionally contains oxidation-sensitive components. The composite further contains at least one surface layer, as well as at least one additional protective layer disposed between the supporting zone and surface layer, and whose matrix is composed substantially of at least one component of the matrix of the supporting zone or cover layer. The protective layer further contains additives that form self-healing layers.

Abstract: A powdery mixture of fine SiC powder with one or more oxide sintering additives of Al2O3, Y2O3, SiO2 and CaO is blended and uniformly dispersed in a polymeric SiC precursor to prepare a matrix-forming polymeric slurry. A preform of SiC fiber, which has quasi-stoichiometric composition with high crystallinity, is impregnated with the polymeric slurry and then hot-pressed at a temperature of 1600° C. or higher in presence of a liquid phase. Since the heat-resistant SiC fiber is used as strengthening fiber, the prepreg is sintered to a dense SiC composite excellent in mechanical properties by one-step hot-pressing.

Abstract: The method for fabricating a ceramic substrate comprises the step of screen-printing a first dielectric material in a first region of a resin film 30 and screen-printing a second dielectric material of a dielectric constant different from that of the first dielectric material in a second region of the resin film 30 to form a layer including on the resin film 30 a high dielectric layer 20a of the first dielectric material and a base dielectric layer 24a of the second dielectric material, the step of releasing the layer from the resin film 30, and the step of sintering the layer released form the resin film 30.

Abstract: Electronically tunable dielectric materials having favorable properties are disclosed. The electronically tunable materials include an electronically tunable dielectric phase such as barium strontium titanate in combination with at least two additional metal oxide phases. The additional metal oxide phases may include, for example, oxides of Mg, Si, Ca, Zr, Ti and Al. The electronically tunable materials may be provided in bulk, thin film and thick film forms for use in devices such as phased array antennas, tunable filters and the like. The materials are useful in many applications, including the area of radio frequency engineering and design.

Abstract: A die (20) comprises metal-rich sections (40a, 40b) which form an inner wall and an outer wall of the die (20), respectively. Gradient sections (42a, 42b) are disposed adjacent to the metal-rich sections (40a, 40b), respectively. Further, a ceramics-rich section (44) is disposed between the gradient sections (42a, 42b). A punch (30) comprises an inner ceramics-rich section (46), a gradient section (50), and an outer metal-rich section (48). In the die (20), the composition ratio of metal gradually decreases from the metal-rich sections (40a, 40b) to the ceramics-rich section (44). Similarly, in the punch (30), the composition ratio of the metal gradually decreases from the metal-rich section (48) to the ceramics-rich section (46).

Abstract: The invention relates to a process for producing a fiber composite material containing fibers with a high hot strength, in particular based on carbon, silicon, boron and/or nitrogen, a pressing compound being produced from fibers, a binder and, if appropriate, fillers and/or additives, which is then pressed in a press mold to form a green body. Various pressing compounds are produced, which contain fibers of different qualities and/or in different proportions, and the press mold is filled with the various pressing compounds in a number of successive steps. The invention also relates to a fiber composite material of this nature.

Abstract: A ceramic arc tube assembly and a method for making a ceramic arc tube are described which simplify the manufacture of ceramic arc tubes by reducing the number of handling and heat treatments required to assemble arc tubes prior to the final sintering operation. In particular, the invention uses transient assembly buttons during intermediate assembly steps which are removed prior to the final sintering operation.

Abstract: A combinatorial library includes a gelcast substrate defining a plurality of cavities in at least one surface thereof; and a plurality of gelcast test materials in the cavities, at least two of the test materials differing from the substrate in at least one compositional characteristic, the two test materials differing from each other in at least one compositional characteristic.

Abstract: A method of making a product which is generally impervious to water including the steps of making a generally homogenous mixture of slate particles and clay, wetting the mixture as necessary to produce a formable composition, forming the wet mixture to a desired configuration, at least partially drying the formed mixture and subjecting the dried formed mixture to a temperature of at least 1100° C. for a time sufficient for at least some of the clay to convert into a binder to bind together the slate particles.

Abstract: A method for producing composite ceramic material is provided wherein a core ceramic structure is produced and simultaneously enveloped with a sleeve of similar material.

Abstract: A process for forming a silicon nitride-bonded silicon carbide honeycomb monolith by a) forming a plasticizable mixture which includes (1) about 60% to 85% by weight, powdered silicon carbide with a median particle size of about 10-40 micrometers; (2) about 15% to 40% by weight, powdered silicon metal with a median particle size of about 5-20 micrometers; and, (3) organic components; b) extruding the plasticizable mixture to form a green honeycomb monolith; c) drying the green honeycomb monolith; and, d) heating the honeycomb monolith to 1450° C. with a hold of 1 hour in an atmosphere of argon; and, e) nitriding the honeycomb monolith between 1450° C. to 1600° C. for a time sufficient to obtain a silicon nitride-bonded silicon carbide body.

Abstract: Methods of forming plasma addressed liquid crystal display ribs are disclosed. An exemplary method includes introducing a glass paste which includes a curable medium into cavities formed in an intaglio collector to define rib structures, which are from the collector to a surface of the substrate, and removing the curable medium from the rib structures on the substrate surface to generate pores in the rib structures. The substrate having rib structures is then dipped into a solution containing an opaque pigment which is absorbed into the rib structure.

Abstract: A method for manufacturing an electrostatic chuck is disclosed wherein a sintered ceramic body having a dielectric layer made from Alumina (Al2O2) and Titanium Nitride (TiN) having a specific range of particle size is heat treated in an oxygen-rich environment in order to produce a uniform dielectric layer having no pores or micro-cracks.

Abstract: 12A high temperature gas turbine component includes an inner core made of a monolithic ceramic material embedded within an outer CMC shell. The inner core may be formed with a through hole, blind hole, wear pads and the like. A method of making the bushing includes the steps of a) forming an inner core of silicon nitride or silicon carbide; and b) applying a ceramic matrix composite material over substantially all of the inner core.

Abstract: A neutron absorbent material and a process for manufacturing said material, the neutron absorbent material having great resistance to mechanical damage and more particularly great resistance to crack propagation, which material contains boron carbide and hafnium in the form of powders of fine grain size, and with the manufacturing process it is possible, by reactive sintering of the two powders, to obtain a boron carbide based material having hafnium boride strata, which process comprises a step consisting of mixing boron carbide and hafnium and a reactive sintering step of the mixture obtained.

Abstract: A method of manufacturing a ceramic matrix composite comprises forming a slurry comprising a ceramic sol, filler particles and a solvent and forming laminates of fibers (12). The laminates of fibers (12) are impregnated with the slurry and are stacked (14) on a mold (10). The stack (14) of laminates of fibers (12) is covered by a porous membrane (16), a breather fabric (18) and a vacuum bag (20). The vacuum bag (20) is evacuated and is heated to a temperature of 60° C. for 10 hours to produce a ceramic matrix composite. The ceramic matrix composite is then heated to a temperature of 1200° C. at atmospheric pressure to sinter the ceramic matrix composite.

Abstract: A hydrocarbon sensor is formed with an electrolyte body having a first electrolyte surface with a reference electrode depending therefrom and a metal oxide electrode body contained within the electrolyte body and having a first electrode surface coplanar with the first electrolyte surface. The sensor was formed by forming a sintered metal-oxide electrode body and placing the metal-oxide electrode body within an electrolyte powder. The electrolyte powder with the metal-oxide electrode body was pressed to form a pressed electrolyte body containing the metal-oxide electrode body. The electrolyte was removed from an electrolyte surface above the metal-oxide electrode body to expose a metal-oxide electrode surface that is coplanar with the electrolyte surface. The electrolyte body and the metal-oxide electrode body were then sintered to form the hydrocarbon sensor.

Abstract: A method of synthesizing negative-thermal-expansion ceramics of synthesizing Zr(1−x)XxW2O8 in which X represents a substituent element for zirconium Zr, and 0≦x <<1, having a negative thermal expansion coefficient, the method comprising mixing two mols of tungsten trioxide WO3 and one mol of the sum of zirconium oxide ZrO2 and a substituent element X in accordance with substitution amount x at a stoichiometrical ratio, further mixing the thus obtained starting material in a powdery form having a particle size distribution including two groups of particles comprising smaller diameter particles with a particle size of 0.

Abstract: X-ray imageable articles, for instance surgical implements or parts therefore which are used in minimally invasive surgical procedures, may be prepared by a process including the steps of: (a) preparing a mixture composition comprising: i) radiolucent particulate material selected from ceramic materials, metallurgic materials, and combinations thereof and having a particulate size of no more than 40 microns, ii) radiopaque particulate material selected from ceramic materials, metallurgic materials, and combinations thereof and having a particulate size of no more than 40 microns, and (iii) at least one polymeric binder material; (b) injection molding the mixture composition into a preform; (c) optionally removing the binder material from the preform; and (d) sintering the preform.

Abstract: A method for manufacturing a ceramic heater includes mixing a conductive ceramic powder, an insulating ceramic powder, a sintering aid powder, and a solvent so as to obtain a slurry, drying the slurry so as to obtain a heating-element material powder, forming a green resistance-heating element from the heating-element material powder, embedding the green resistance-heating element in a ceramic substrate, and firing a resultant assembly. Water is used as the solvent. Drying of the slurry is performed by use of a fluidized-bed drying apparatus, a rotary drying apparatus, or a vibratory drying apparatus and, the apparatus being employed in combination with a medium for pulverization.

Abstract: A ceramic matrix composite part having elongated cooling channels within the wall thereof is manufactured by inserting decomposable inserts within a woven ceramic fiber preform. The inserts are tows of continuous carbon fibers surrounded by a carbonaceous filler, and are inserted where the channels are desired. The preform, with the inserts in place, is disposed within a mold. A ceramic matrix material is added and the fiber preform is consolidated with the ceramic matrix material. The consolidated part is then heated to thermally decompose the inserts to create the elongated channels within the part. The inserts may be flexible and woven into the preform using an automated weaving loom, or they may have limited flexibility and be inserted by machine or by hand.

Abstract: Plasma addressed liquid crystal display ribs are formed by a method which includes forming a temporary mask on portions of a surface of a substrate, depositing a layer of a glass paste having a curable medium and at least one pigment blended therein over the substrate and temporary mask, micro-molding rib structures from the glass paste on the substrate surface in areas between the masked sections, removing any residual layer of paste material present on the temporary mask, removing the temporary mask from the substrate, and firing the substrate with micro-molded rib structures thereon.

Abstract: A method for fabricating electrically conductive silicon carbide articles by doping and sintering submicron silicon carbide particles using sub-micron alumina as the dopant source. Submicron alumina particles are made by milling aluminum powder. Despite the ductility of metallic aluminum, it is successfully ball milled in an aqueous medium through the creation and abrasion of successive layers of an alumina skin to yield alumina particles as small as 0.01 &mgr;m across. When suitably composed mixtures of the silicon carbide and alumina are molded into a green body and heated sufficiently in a non-oxidizing furnace atmosphere, the alumina breaks down to metallic aluminum which diffuses into the silicon carbide. The small particle sizes and the presence of a sintering aid enable rapid processing kinetics which favor saturation of the silicon carbide by the aluminum and inhibit grain growth.

Abstract: A novel process for fabricating metal clad laminates used in the manufacture of printed wiring boards. The process which eliminates multiple use separator plates within laminate books during buildup and pressing, utilizes a sacrificial separator sheet between copper sheets and wherein the separator sheet remains intact throughout the pressing and cutting steps and is finally removed after the laminates have been sized to the desired dimensions. This process provides time and cost savings, as well as a significant increase in quality and quantity of the laminates produced.

Abstract: A powder bed (32) is built up by repeated deposition of a slurry that contains powder. Layers are made by depositing a liquid dispersion of the desired powdered material, which then slip-casts into the forming powder bed to make a new layer (34). The slurry may be deposited in any suitable manner, such as by raster or vector scanning, or by a plurality of simultaneous jets that coalesce before the liquid slip-casts into the bed, or by individual drops, the deposits of which are individually controlled, thereby generating a regular surface for each layer.

Abstract: The invention relates to a filter element and its manufacture to be used in removal of liquid from solids containing material to be dried in a capillary suction dryer which filter element contains a ceramic microporous layer having the pore size under 5 micrometer and supported by a ceramic internal layer having recess areas for liquid flowing. The internal layer is made of at least one substrate which continuously surrounds at least one recess area and which ceramic internal layer is surrounded by at least one essentially continuous microporous surface layer.

Abstract: An improved method for manufacturing a porcelain object in a desired shape, from a mixture of at least clay, feldspar and quartz. According to the method, an aqueous dispersion of vinyl acetate and ethylene based copolymer is added to the mixture, and the mixture transformed into an aqueous mass in the shape of a foil with a thickness of 50 &mgr;m to 3 mm and dried. The dried foil is then formed into a desired object shape, and permanently hardened by a ceramic firing process. The dried foil may be brought into the desired object shape by known processes such as rolling, laminating, calendering, cutting, punching, paper folding methods and deep drawing. Once brought into the desired object shape, no drying is required before ceramic firing.

Abstract: A method for the production of a silicon nitride filter includes heat treating in nitrogen a green body containing from 40 to 90% of metal silicon particles having an average particle size of from 1 to 200 &mgr;m and from 10 to 60% of a pore forming agent. The green body contains at least 90% of the metal silicon particles and the pore forming agent and forms a porous product. The filter is excellent in heat resistance, corrosion resistance, acid resistance and mechanical strength and suitable for dust arresting or dust removing and is particularly suitable as a filter for particulates. The porosity of the silicon nitride filter is from 40 to 70% and the cumulative pore volume of pores with diameters of at most 1 &mgr;m is from 1 to 15 vol % of the total pore volume.

Abstract: This invention relates to an aging resistant SiC igniter having a second layer of recrystallized SiC within the body.

Abstract: A creep-resistant and chemical-resistant ceramic refractory composition includes a mixed oxide of the general formula R3Al5O12 where R is at least one of Dy, Ho, Y, Er, Tm, Yb, and Lu, the mixed oxide having a garnet structure and comprising in solid solution at least one dopant of a transition metal element and a rare-earth element, which effects in the composition enhanced optical emission in at least one spectral range.

Abstract: A method for chemically etching of a foam glass layer to provide at least one cavity pattern in the foam glass layer. The method utilizes a substrate with at least one major surface suitable for receiving a glass layer. At least one layer of a glass paste composition in then applied onto the major surface of the substrate. The substrate and glass paste composition are then heated to a temperature sufficient enough to obtain a foam glass layer bonded to the major surface of the substrate. At least a portion of the foam glass layer is chemically etched to obtain at least one cavity pattern in the foam glass layer. The chemical etching of the foam glass layer results in an anisotropic etching rate.

Abstract: Process for the manufacture of dental restorations using high strength ceramic components. A wax pattern is built around a high strength ceramic component on a die. The wax pattern with the high strength ceramic component is surrounded with investment material. The wax is burned out, leaving a mold with the high strength ceramic component. The mold is filled with a ceramic material, covering the high strength ceramic component, creating a dental restoration.

Abstract: A method for producing shaped articles of ceramic composites provides a high degree of dimensional tolerance to these articles. A fiber preform is disposed on a surface of a stable formed support, a surface of which is formed with a plurality of indentations, such as grooves, slots, or channels. Precursors of ceramic matrix materials are provided to the fiber preform to infiltrate from both sides of the fiber preform. The infiltration is conducted under vacuum at a temperature not much greater than a melting point of the precursors. The melt-infiltrated composite article substantially retains its dimension and shape throughout the fabrication process.

Abstract: A ceramic powder of grains having a shape-anisotropy is mixed with a calcined or uncalcined (or both) powder of a ceramic raw material. A ceramic slurry containing the produced mixed powder, a solvent and a binder is prepared and the ceramic slurry is formed into a sheet. A laminate comprising a plurality of the sheets laminated to each other is uniaxially pressed to form an oriented product in such a manner that the length of the laminate in the direction parallel to the pressing axis becomes larger than that before the pressing, and the area of a plane perpendicular to the pressing axis of the laminate becomes larger than that before the pressing. The oriented formed product is fired and sintered.

Abstract: A method of manufacturing a ceramic matrix composite comprises forming a slurry comprising a ceramic sol, filler particles and a solvent and forming laminates of fibres (12). The laminates of fibres (12) are impregnated with the slurry and are stacked (14) on a mould (10). The stack (14) of laminates of fibres (12) is covered by a porous membrane (16), a breather fabric (18) and a vacuum bag (20). The vacuum bag (20) is evacuated and is heated to a temperature of 60° C. for 10 hours to produce a ceramic matrix composite. The ceramic matrix composite is then heated to a temperature of 1200° C. at atmospheric pressure to sinter the ceramic matrix composite.