Abstract: Porous solid bodies, especially carbon bodies, are densified by chemical vapor deposition by establishing a thermal gradient within the body, thermally decomposing a gaseous precursor so deposit an electrically and thermally conductive deposit (e.g. carbon) within the body, and shifting the thermal gradient toward the lower temperature zone as deposition proceeds, by means of induction heating.

Abstract: Bodies (3) such as tiles, plates, slabs or bricks of Refractory Hard Material (RHM) or other refractory composites are bonded to the cathodes or to other components, in particular to a carbon cell bottom (1), of a cell for the production of aluminium by electrolysis of a cryolite-based molten electrolyte, made of carbonaceous or other electrically conductive refractory material, by a non-reactive colloidal slurry (4) comprising particulate preformed RHM in a colloidal carrier selected from colloidal alumina, colloidal yttria and colloidal ceria. The slurry usually comprises preformed particulate TiB.sub.2 in colloidal alumina. The bodies (3) are usually TiB.sub.2 --Al.sub.2 O.sub.3 composites. The bonding is achieved simply by applying the slurry and allowing it to dry.

Abstract: A gas diffusion electrode is provided with antipercolation coating by bonding a free-standing film, e.g. of polysulfone or polypropylene, to a catalyzed carbon cloth utilizing a filled polysulfone/N-MP adhesive which is subjected to solvent exchange with water by either a thermal bonding as in the case of a free-standing microporous polysulfone film or mechanical bonding as in the case of a commercial microporous polypropylene film.

Abstract: Carbon fibers having substantially increased active surface area and total surface area are used to enhance carbon fiber bonding to matrix materials in carbon fiber products. The enhanced active surface area and total surface area are produced by carbon removal in disordered regions as well as perfect basal plane regions by catalytic silver oxidation.

Abstract: An infusiblized, or infusiblized and slightly carbonized fiber of optically anisotropic pitch type is combined with a phenolic resin fiber to produce a high bulk density carbon fiber structure in the form of a laminate of mutually entangled carbon fiber sheets with improved handleability of fiber sheets and improved stability of a laminate structure formed through entanglement. A high flexural strength carbon-carbon composite material with a high volume fiber content is produced by impregnation with a precursor of carbon and subsequent carbonization of the carbon fiber structure of the kind as described above or a fiber laminate of mutually entangled sheets of the infusiblized, or infusiblized and slightly carbonized fiber of optically anisotropic pitch type blended with the phenolic resin fiber.

Abstract: Graphite and/or carbon surfaces are coated with a titanium nitride coating by exposing the substrate to electric arc thermal spray process wherein titanium wire as the source of titanium and nitrogen is used as the propelling (atomizing) gas.

Abstract: A method is provided for preparing preceramic polymers and and silicious ceramic materials which derive therefrom. The preceramic polymers are polysiloxanes which are synthesized by catalytically activating Si--H bonds in a hydridosiloxane starting material and replacing the activated hydrogen atoms with non-hydrogen substituents. These preceramic polysiloxanes are pyrolyzed in a selected atmosphere to give the desired ceramic product. Ceramic products which may be prepared by this technique include silica, silicon oxynitride, silicon carbide, and metal silicates.

Abstract: A method for rapidly providing an impervious carbon substrate such as carbon fibers with a carbide coating, in atmospheric pressure, so as to provide a carbide layer bound to the carbon substrate. A carbide layer on the impervious carbon substrate is provided by coating the substrate with a concentrated solution of a carbide forming element in compound dissolved in a suitable solvent. The carbon substrate is heated to a temperature at which the carbide forming element in compound decomposes and chemically reacts with the carbon substrate to form the desired carbide layer.

Abstract: The method for forming a carbon resistance in a printed wiring board comprises, in a method for forming a carbon resistance in the circuit of a printed wiring board,a process of depositing a thermoset carbon resistance layer coated on a laminated film on the surface of the circuit, a process of thermosetting the carbon resistance layer along the disposal position necessary for the circuit, and a process of removing the uncured layer of the carbon resistance layer from the circuit surface after the thermosetting process.

Abstract: The method for forming a carbon resistance in a printed wiring board is characterized in that, in a method for forming a carbon resistance in the circuit of a printed wiring board, a carbon resistance to be disposed in the circuit which is formed in a laminated film is previously deposited on and correspondingly to the surface of said circuit, and the protective film of the carbon resistance of the laminated film is removed.

Abstract: A process for treating an electrode to form a protective coating comprising applying a precursor of an impregnate material to the surface, controlling the depth of penetration, induction heating the surface under controlled conditions of power, frequency and relative velocity to bring the surface to the treat temperature and quench cooling the surface.

Abstract: A method for rapidly providing a porous or impervious carbon substrate with a carbide phase, in atmospheric pressure, so as to provide maximum binding between the carbide and the carbon substrate. A carbide phase on the porous or impervious carbon substrate is provided by chemically reacting the substrate with a concentrated solution of a carbide forming element in compound dissolved in a suitable solvent. The carbon substrate is heated to a temperature at which the compound decomposes and chemically reacts with the carbon substrate to form the desired carbide phase.

Abstract: A method of producing a diamond or diamond-like film having a desired profile which involves providing a solid carbon substrate having a surface shaped to the desired profile, creating a thin carbide layer on the profiled surface growing a diamond or diamond-like film on the carbide layer, removing the carbon substrate and optionally also removing the carbide layer.

Abstract: A carbon/carbon composite having oxidation resistance is produced by filling the voids of a carbon/carbon composite comprising 10-70% by volume of carbon fibers and 5-90% by volume of a carbonaceous matrix and having a void percentage of 10-55%, with at least one of carbon and a ceramic by chemical vapor infiltration and then coating the deposit surface with a ceramic or both ceramic and carbon by chemical vapor deposition.

Abstract: A method for producing lightweight silver-nickel composite electrodes by(1) infiltrating a graphite fiber plaque with a suspension of finely divi nickel powder in an aqueous solution of AgNO.sub.3 ;(2) drying the graphite fiber plaque to produce a coating of AgNO.sub.3 crystals and nickel particles on the surfaces of the graphite fibers;(3) heating the coated graphite fiber plaque at a temperature about the melting point of AgNO.sub.3 but below the decomposition temperature of AgNO.sub.3 until the AgNO.sub.3 melts and wets the nickel particles and the surfaces of the graphite fibers; and(4) heating the molten AgNO.sub.3 coated graphite fiber plaque at a temperature from the decomposition temperature of AgNO.sub.3 to about 600.degree. C. until the AgNO.sub.3 decomposes to form a thin uniform silver metal coating over the nickel particles and the surfaces of the graphite fibers.The silver-nickel particle coated graphite plaques is electrochemically treated to convert the silver to silver active material (Ag.

Abstract: An electroacoustic diaphragm is provided, which diaphragm comprising a pyrolytic graphite film obtained from a polymer selected from polyoxadiazole, an aromatic polyimide obtained by polycondensation of pyromellitic acid and an aromatic diamine, polybenzthiazole, polybenzbisthiazole, polybenzoxazole, polybenzbisoxazole, poly(pyromellitimide), poly(m-phenyleneisophthalamide), poly(m-phenylenebenzoimidazole), poly(m-phenylenebenzobisimidazole), polythiazole and poly(m-phenylenevinylene. The graphite film has a discontinuous layer of a polymeric material formed on and in the film whereby not only good electroacoustic characteristics, but also good mechanical strength and good adhesion of an adhesive applied thereof are obtained. A method for fabricating such diaphragm is also described.

Abstract: A pyrolytic boron nitride boat having a cavity suitable for use in growing and doping semi-conductor crystals such as gallium arsenide and said cavity having a roughened surface formed of substantially uniform projected nodules, disturbances, or ridges.

Abstract: Renewable composite microelectrodes for electrochemical applications are formed by an initial coating on an elongated conductive substrate of less than 500 micrometers over at least a portion of its length with a modifier composition, and a superposed coating of electronically resistive polymer. The initial coating is exposed only at the tip portion of the microelectrode. The initial coating may be an absorbed layer of the modifier, a homogeneous layer of a polymeric matrix with the modifier dispersed therein, or a layer of a polymer with a modifier in its chain. The modifier provides distinctive properties to the surface of the electrode which may be electroactivity, inclusion, acidic/basic, complexing/chelating or electrocatalysis. The microelectrode will normally be used with only the tip portion thereof immersed in the solution, and it may be renewed by removing the contaminated tip portion.

Abstract: Carbon-transition metal composite formed via pyrolytic decomposition of a polycyanogen in the presence of a transition metal or a salt thereof.

Abstract: A process for the formation of alumina containing carbon fiber mats is provided. The process comprises dispersing an alumina precursor solution in the mat, converting the precursor to an insoluble hydroxide precipitate and hydrolizing the precipitate to form alumina nodules dispersed throughout the mat. Also provided is an alumina containing carbon fiber mat comprising carbon fibers and nodules of alumina, which are substantially uniformly dispersed throughout the mat, and a sodium sulfur cell having a sulfur compartment containing such a mat.

Abstract: An improved cathode structure for Hall-Heroult cells for the electrolytic production of aluminum metal. This cathode structure is a preform fiber base material that is infiltrated with electrically conductive titanium diboride using chemical vapor infiltration techniques. The structure exhibits good fracture toughness, and is sufficiently resistant to attack by molten aluminum. Typically, the base can be made from a mat of high purity silicon carbide fibers. Other ceramic or carbon fibers that do not degrade at temperatures below about 1000 deg. C can be used.

Abstract: A process for producing almost perfect graphite films and fibers at lower graphization temperatures wherein a film or fiber of a polymer selected from a defined group is subjected to a preliminary heat treatment at a temperature of 400.degree. to 700.degree. C., under tension, in vacuo or in an inert gas, and then heat treating the film or fiber at a temperature of at least 1600.degree. C. in vacuo or in an inert gas, to graphitize the film or fiber. The process can be modified to produce graphite films having excellent electric conductivity and mechanical properties, by heat treating a polymer selected from a second defined group at a temperature of at least 1800.degree. C. in vacuo or in an inert gas, impregnating the film with a binder component, and then heat treating the impregnated film at a temperature of not more than 1400.degree. C.

Abstract: A method is disclosed for creating a strong point for the attachment of carbon composites to metallic bodies that is suitable at high temperatures (1600.degree. F.) as well as ambient temperatures. A pocket of suitable dimensions and depth is molded into the carbon composite structure on both sides at an edge, with the edge relieved and rounded. A hole for a fastening member is molded or drilled in the approximate center of the pocket. After preparation of the surface the pocket, through hole, and relieved edge are nickel-plated to produce a rigid strong point. A doubler can be brazed to the nickel plate to strengthen the bond. The disclosed method can be used for attaching any type of electrically conductive composite material to a metallic structure.

Abstract: A process for converting in depth a carbon or graphite preform object to a silicon carbide object, silicon carbide/silicon object, silicon carbide/carbon-core object, or a silicon carbide/silicon/carbon-core object, by contacting it with silicon liquid and vapor over various lengths of contact time in a reaction chamber. In the process, a stream comprised of a silicon-containing precursor material in gaseous phase below the decomposition temperature of said gas and a coreactant, carrier or diluent gas such as hydrogen is passed through a hole within a high emissivity, thin, insulating septum into the reaction chamber above the melting point of silicon. The thin septum has one face below the decomposition temperature of the gas and an opposite face exposed to the reaction chamber. Thus, the precursor gas is decomposed directly to silicon in the reaction chamber. Any stream of decomposition gas and any unreacted precursor gas from the reaction chamber is removed.

Abstract: Described is a way of sealing a carbon body such as monolithic graphite tooling so that it retains its vacuum integrity through numerous thermal cycles typical of thermoplastic processing. This is accomplished by (a) applying to the body surface a coating formulation composed of a carbon-filled solution of a polyamic acid formed by reaction between pyromellitic acid dianhydride and 2,2-bis[4-(aminophenoxy)phenyl]hexafluoropropane, and (b) heat curing the coated body to cause the polyamic acid to imidize into a thermally cured polyimide.

Abstract: A cathode/membrane assembly for an electrolysis cell capable of producing hydrogen in a cathode compartment, utilizes as the cathode material on a proton-permeable solid-electrolite ion-exchange membrane, a layer of porous graphite in the form of carbonaceous fibers coated with tungsten carbide. The graphite felt can be impregnated with an aqueous solution of para-ammoniumtungstate or with an alcoholic solution of tungsten hexachloride and the tungsten compounds are then converted to the tungsten oxides. The tungsten oxide coated graphite felt is then subjected to carburization at a temperature of 620.degree. to 950.degree. C. in a carburizing atmosphere, preferably a flowing CO/CO.sub.2 mixture.

Abstract: A process for coating a carbon or graphite object with silicon carbide by contacting it with silicon liquid and vapor over various lengths of contact time. In the process, a stream of silicon-containing precursor material in gaseous phase below the decomposition temperature of said gas and a co-reactant, carrier or diluent gas such as hydrogen is passed through a hole within a high emissivity, thin, insulating septum into a reaction chamber above the melting point of silicon. The thin septum has one face below the decomposition temperature of the gas and an opposite face exposed to the reaction chamber. The precursor gas is decomposed directly to silicon in the reaction chamber. A stream of any decomposition gas and any unreacted precursor gas from said reaction chamber is removed. The object within the reaction chamber is then contacted with silicon, and recovered after it has been coated with silicon carbide.

Abstract: High strength composite fibers are disclosed comprising a core, e.g., of carbon or the like, and a thin and uniform, firmly adherent electrically conductive layer of an electrodepositable metal, e.g., of nickel or the like. The composite fiber can be produced by electrodeposition from an electrolyte onto the core but the procedure must use external voltages high enough both (i) dissociate the metal at the core and (ii) to mucleate the metal through the boundary layer into direct contact with the core. Such composite fibers are chopped to shortened lengths to provide chaff, which is effective as a radar countermeasure.

Abstract: A coil comprising a carbon filament winding with fused particulate insulative coating therearound and method of producing such carbon filament coil.

Abstract: An electrically conductive fibrous material and a process for preparing the same from a thermally stabilized acrylic fibrous material are provided. The thermally stabilized acrylic fibrous material is first contacted with cuprous ions to produce a cuprous ion-impregnated fibrous material, and subsequently is subjected to a sulfiding agent capable of sulfiding cuprous ions, and preferably washed, to produce thermally stabilized acrylic fibrous material having covellite copper sulfide in association therewith. Also provided are electrically conductive composites and a process for preparing the same by incorporating the fibrous material prepared in accordance with the process within a substantially continuous polymeric matrix.

Abstract: A method for synthesizing diamond, which comprises:(a) generating a plasma by electric discharge in a gas selected from the group consisting of a hydrocarbon gas, hydrogen gas, an inert gas and a mixture thereof,(b) decomposing a carbon source by the plasma to form plasma gas containing carbon ions or carbon radicals,(c) effecting adiabatic expansion of the plasma gas to precipitate diamond.

Abstract: An electroconductive core-sheath composite fiber comprising a core containing an electroconductive substance and a sheath formed of a fiber-forming polymer, which surrounds the core, wherein the core is completely covered with the sheath, the electric resistance of the surface of the fiber is lower than 10.sup.10 .OMEGA./cm, and the ratio of the electric resistance (.OMEGA./cm) of the surface to the internal electric resistance between the sections is lower than 10.sup.3.

Abstract: A method for making a carbon-graphite component suited for use in an electrochemical cell, said component having a desired controlled pore structure having a desired mean pore size within a predetermined pore size range and a maximum pore size.

Abstract: Thin carbon products are produced from cellulose material by impregnation with a carbonaceous material followed by curing and baking. The baked product may optionally be graphitized depending on end use.

Abstract: A method for treating a carbon or graphite electrode comprising contacting the electrode with a phosphate-containing compound and a halide-containing compound. The treated electrode is oxidation retarded and inhibits non-conductive film formation between the electrode and a copper electrode holder, thereby inhibiting arcing between the electrode and the electrode holder when used in an electric arc furnace.

Abstract: A protective layer for carbonaceous materials, especially graphite electrodes, applied by plasma-coating method comprised of 65-98 w/o of metal aluminum, 1-20 w/o of combined metal silicon with silica (SiO.sub.2) and up to 15 w/o of oxygenous compounds of aluminum. The resistivity of the layer is 0.07.10.sup.-6 ohm.m up to 0.3.10.sup.-6 ohm.m at 20.degree. C. and 0.12.10.sup.-6 ohm.m up to 0.7.10.sup.-6 ohm.m at 400.degree. C.The method of producing the protective layer comprises the following steps of directing a plasma flame of a water stabilized plasma burner toward the carbonaceous material, and feeding into a plasma flame a particulate composition comprising between about 85 w/o to about 99 w/o of metallic aluminum having a particle size of between about 0.09 to about 0.180 mm and between about 1 to about 15 w/o of silicon having a particle size of between about 0.07 to about 0.165 mm.

Abstract: A method of producing a multiple thermocouple having a conductive open-cellular foam matrix, a portion of which forms a first pole with a plurality of discrete conductors of a different material from the foam matrix embedded in the foam having a portion of each of the discrete conductors being exposed on the insides of the cells of the foam forming a plurality of thermocouples. The remaining surface area inside the foam's cells not having an exposed discrete conductor thereon can be insulated. A second pole member is provided. Means to contact the discrete conductors in the foam and convey current produced by the thermocouples to the second pole of the thermocouple completes the multiple thermocouple. Such means to contact the discrete conductors can provide the heat to excite the thermocouples or such heat can come from other sources.

Abstract: A highly electroconductive graphite continuous filament is described, which is composed of a carbon filament as a substrate and a graphite layer having a layer spacing d (0,0,2) of not larger than 3.363 angstroms as an outer skin layer. The graphite continuous filament is prepared by depositing easily graphitizable carbon on the substrate and heat-treating the carbon-deposited substrate at a temperature of at least 2,500.degree.C.

Abstract: For use in trickle bed electrolytic cells, the preferred and illustrated embodiment sets forth an improved graphite composite chip. It is a chip characterized by having a much higher percentage with a more uniform coating thereon. The coating has the form of a mix of carbon and Teflon on graphite chips. It is more uniform and applied to both sides of the chips. This improves current flow and distribution in an electrolytic cell such as a hydrogen peroxide cell. One procedure taught herein is a method of making such composite chips on graphite wherein carbon in particulate form is mixed with water and particulate Teflon dispersion and is added to graphite chips of a selected mesh size; after mixing, the water is drained and all water is removed by a vacuum in a rotary evaporator whereupon the dried material is then sintered for a specified time and temperature.

Abstract: The invention provides a composite carbon or graphite having desirable properties such as corrosion and wear resistance. The invention combines a graphite substrate with a protective porous zone of silicon carbide. The whole body of graphite plus silicon carbide then is infiltrated with aluminum phosphate. An adhered barrier of silicon carbide, ranging in thickness between 0.015 and 0.050 inch thick is integrated with a graphite stratum to form a very hard surface, resistant to mechanical and chemical wear. The silicon carbide barrier is closely compatible to the graphite substrate, in resistance to thermal shock and in qualities of thermal expansion. In order to improve oxidation resistance further, a new composition was formed by infiltrating aluminum phosphate through the silicon carbide into the graphite to form a single body of composite graphite.

Abstract: The invention provides carbon fibers coated on the surface with a layer of an amorphous silicon carbide of the composition Si.sub.x C.sub.y, x and y each being a positive number with the proviso that the ratio y/x is in the range from 0.5 to 2.5, formed by the exposure of the carbon fibers to low temperature plasma generated in an atmosphere containing an organosilicon compound having no oxygen or chlorine atom directly bonded to the silicon atom in the molecule. The carbon fibers are imparted with greatly increased resistance against air oxidation at high temperatures as well as remarkably improved affinity or wettability with plastics and molten metals along with very low reactivity with molten metals so that the carbon fibers are useful as a reinforcing material in the composite materials of carbon fiber-reinforced plastics and metals.

Abstract: A method of forming a coated article is described. The article is composed of a carbon body having a thermochemically deposited coating which renders the body resistant to oxidation at high temperatures. A volatile gaseous halide of silicon is partially reduced to form a lower halide in a first reaction zone having a first pressure and separated from the body. The lower halide is flowed into a second reaction zone maintained at a pressure lower than the pressure in the first reaction zone. A gaseous alloying agent is introduced into the second reaction zone. The agent includes one or more elements selected from the group consisting of carbon, oxygen, aluminum, and nitrogen. As a consequence, a liquid phase intermediate compound is deposited on the substrate body which is thereafter thermochemically reacted to produce a coating of the silicon alloy.

Abstract: One-component epoxy resin coating materials comprising(A) an epoxy resin or a mixture of epoxy resins,(B) as hardener for the epoxy resin at least one aromatic dicarboxylic acid dihydrazide or a triazine compound of the formula I ##STR1## (R=alkylamino or dialkylamino having 1 or 2 carbon atoms in the alkyl moieties, phenylamino or hydrazino) and(C) an anti-sagging agent or an inorganic filler or a mixture of anti-sagging agent and an inorganic filler, are used for the coating of fixed resistors. The resultant coatings exhibit good heat, moisture and cracking resistance.

Abstract: A process for selectively depositing a tungsten or tantalum refractory metal on a graphite piece, particularly for X-ray tube anodes, wherein the graphite piece is masked on selected surfaces, an intermediate layer of a coating material is deposited on unmasked surfaces to promote adhesion of the refractory metal followed by removal of the masking and deposition of the refractory metal on all surfaces, and finally removing from the formerly masked surfaces refractory metal poorly adhered thereto.

Abstract: An anodic assembly immersible in a fluoborate electrolytic bath in an electroplating process for plating tin and similar metals. The assembly is constituted by a cylindrical basket containing a replenishable pile of solid pieces of the plating metal, the basket being formed by a perforated carbon tube closed at its bottom by a carbon plug. The outer surface of the tube is impregnated with a resin acting as a reinforcing skin to prevent cracking when the tube is drilled to create the required perforations.

Abstract: A carbonaceous article, e.g., a carbon or graphite electrode, is provided with an oxidation prohibitive coating comprising a compliant, low strength, porous, sintered, particulate, refractory, ceramic material. A cover layer is preferably applied over this compliant, low strength, ceramic layer, the cover layer comprising a rigid, glassy substance which is plastic and flowable at temperatures above about 750.degree. C.

Abstract: An improved large surface, quasi-monocrystalline silicon crystal bodies of the type used in solar cells. The bodies are produced by reacting at least the surface of a carbon fiber fabric with molten silicon under conditions of temperature and viscosity sufficient to cause the molten silicon to penetrate the fabric and produce silicon carbide at at least the surface of the fibers, and immediately thereafter coating the thus reacted fabric with metallic silicon from a second molten silicon bath to produce a silicon coating.

Abstract: A coil comprising a carbon filament winding with fused particulate insulative coating therearound and method of producing such carbon filament coil.

Abstract: Improved coating and method of forming a nondewettable coating in a reactive carbon monoxide atmosphere wherein a small portion of palladium, platinum or mixture thereof is added to the coating mixture before the mixture is applied to the substrate. Alternatively, in the case of electrolytic deposition, a thin layer of palladium, platinum or mixture thereof is, e.g. electrolessly or by sputtering or silkscreening, deposited on a substrate before a tin or tin alloy coating is deposited, such as by sputtering, silkscreening, etc. The reaction temperature required to form a nondewettable bond is reduced or increased depending on the tin alloy content, but it appears that if platinum or palladium is participating in the reaction for the same alloy, the temperature for achieving the bond appears to be reduced.

Abstract: A process and an apparatus for depositing thin, amorphous carbon films having extreme hardness on a substrate is described. An enclosed chamber maintained at less than atmospheric pressure houses the substrate and plasma producing elements. A first electrode is comprised of a cavity enclosed within an RF coil which excites the plasma. A substrate located on a second electrode is excited by radio frequency power applied to the substrate. A magnetic field confines the plasma produced by the first electrode to the area away from the walls of the chamber and focuses the plasma onto the substrate thereby yielding film deposits having higher purity and having more rapid buildup than other methods of the prior art.