Abstract: A mixture of carbon-containing fibers, such as mesophase or isotropic pitch fibers, and a suitable matrix material, such as a milled pitch, is compressed while resistively heating the mixture to form a carbonized composite material having a density of about 1.5 g/cm3, or higher. The composite material is formed in under ten minutes. This is a significantly shorter time than for conventional processes, which typically take several days and achieve a lower density material. Consequently, carbon/carbon composite materials having final densities of about 1.6-1.8 g/cm3, or higher are readily achieved with one or two infiltration cycles using a pitch or other carbonaceous material to fill voids in the composite and rebaking.

Abstract: A method for producing self-supporting activated carbon structures is disclosed. The method comprises the steps of mixing a granular activated carbon, a binder material, a carbonization agent, and a liquid to produce a semi-plastic mixture; compacting the mixture using compacting pressures of or greater than about 100 pounds per square inch to form a three-dimensional structure; and heating the structure to an elevated temperature of or greater than about 300° C. to produce a self-supporting activated carbon structure. The granular activated carbon is of any particle size between approximately 4 and 325 mesh U.S. Sieve Series, and the binder is a ground cereal grain, cereal rain flour or a tuber flour. The resultant structure may then be cooled to near-ambient temperatures under an essentially inert atmosphere. Such structures can exhibit good mechanical strengths, adsorption capacities nearly equivalent to those of the activated carbon used in their preparation, and appreciable electrical conductivity.

Abstract: A method is provided for forming items from ecoceramic-based silicon-carbide. A wood preform is machined to a general shape having over- or undersized dimensions. The preform is pyrolyzed to transform the wood of the preform to a porous, carbonaceous material that retains the general shape of the preform. The preform is then machined to final, net-shape dimensions and immersed in liquid silicon or silicon alloy that penetrates and infuses the preform. The infused preform is held at a temperature sufficient to cause the transformation of the material in the preform to silicon carbide, completing formation of the item. Also provided is a method of forming ecoceramic-based tooling and composite components using the tooling.

Abstract: A method for manufacturing carbon-carbon composites includes steps of producing a mat using carbon fiber, carbon fabric, carbon sheet, or staple fiber; laminating at least three layers of mats; producing a preform using the laminated mats with a needle punching method; performing a first thermal treatment process on the produced preform at a predetermined temperature; densifying the first-thermal-treated preform; performing a second thermal treatment process on the densified preform; forming a predetermined shape out of the second-thermal-treated preform; and performing an oxidation resistant treatment process of the shaped preform. A brake disk manufactured by the above method has high compression and shear strength as well as low friction coefficient for use in civil aircraft requiring a low friction coefficient and high loads. A brake disk produced with a liquid impregnation method can bear thermal and mechanical loads at high temperatures.

Abstract: A method of making a ceramic article includes the providing a member. The member includes a cellulose-based material. The cellulose-based material is carbonized to carbon. At least a portion of the member is covered with silica sand after carbonization. At least a portion of the carbon of said member, which has been carbonized, is converted to silicon carbide.

Abstract: Process for producing hollow bodies comprising fibre-reinforced ceramic materials, where cores whose shape corresponds to that of the hollow spaces are produced in a first step, a green body is produced in a second step by introducing the abovementioned cores and a press moulding compound into a mould, where the press moulding compound comprises carbon fibres and/or carbon threads and pitch and/or resins, the green body is cured in a third step by heating under pressure, the cured green body is carbonised in a fourth step by heating in the absence of oxidants to form a C/C body, and, if desired, the C/C body is infiltrated with liquid metal with retention of its shape in a fifth step, with at least partial formation of carbides occurring, where the cores comprise a material which in the fourth step melts without decomposition at a temperature above the curing temperature of the shaping by pressing of the press moulding compound; hollow bodies produced by this process and also their use as brake disks, clutch

Abstract: A resin transfer molding (RTM) process is disclosed for rapidly filling a fibrous preform and/or a rigid, porous body with high viscosity resin or pitch. The process is suitable for impregnated multiple porous bodies stacked in a single mold. The process uses a fibrous preform or rigid porous body which is placed into a mold matching the desired part geometry. A resin is injected into the mold at temperature and pressure. After cooling, the infiltrated component is removed from the mold. The mold is constructed from two halves fitted to form at least one mold cavity. A gate fitted with a nozzle is set into one of the mold halves, and a valve admits resin or pitch into the gate area. Venting or vacuum can be applied to the mold. The mold is held in a hydraulic press and an extruder, optionally fitted with an accumulator, supplies molten resin or pitch to the mold.

Abstract: A method of making a ceramic article includes the providing a member. The member includes a cellulose-based material. The cellulose-based material is carbonized to carbon. At least a portion of the member is covered with silica sand after carbonization. At least a portion of the carbon of said member, which has been carbonized, is converted to silicon carbide.

Abstract: A fiber-reinforced silicon carbide composite is produced by preparing a fiber prepreg containing a powdered silicon and a resin and molding the prepreg to yield a green body having a desired shape, or laminating a fiber prepreg containing a resin and a woven fabric prepreg containing a powdered silicon and a resin in alternate order and molding the laminate to yield a green body having a desired shape; carbonizing the green body at 900° to 1350° C. in an inert atmosphere; subjecting the carbonized body to reaction sintering at a temperature of 1300° C. or more in vacuo or in an inert atmosphere to form open pores; and infiltrating molten silicon into the sintered body having open pores at a temperature of about 1300° to 1800° C. in vacuo or an inert atmosphere.

Abstract: A porous material suitable for use in a bearing rolling element. The porous material is obtained by a process which includes mixing degreased bran derived from rice bran with a thermosetting resin before kneading, subjecting a kneaded mixture to a primary firing in an inert gas at a temperature in a range of 700 to 100° C., pulverizing the kneaded mixture after the primary firing into carbonized powders sieved through a screen of 100-mesh, mixing the carbonized powders or the carbonized powders and ceramic powders with a thermosetting resin before kneading, pressure-forming a kneaded mixture thus obtained at a pressure in a range of 20 to 30 MPa, and applying a heat treatment again to a formed kneaded mixture in the inert gas at a temperature in a range of 100 to 1100° C.

Abstract: A process for forming a porous silicon nitride-silicon carbide body, the process comprising (a) forming a plasticizable batch mixture comprising (1) powdered silicon metal; (2) a silicon-containing source selected from the group consisting of silicon carbide, silicon nitride and mixtures thereof; (3) a water soluble crosslinking thermoset resin having a viscosity of about 50-300 centipoise; and, (4) a water soluble thermoplastic temporary binder; (b) shaping the plasticizable batch mixture to form a green body; (c) drying the green body; (d) firing the green body in nitrogen at a temperature of 1400° C. to 1600° C. for a time sufficient to obtain a silicon nitride-silicon carbide structure.

Abstract: A silicon carbide honeycomb body is made by shaping a plasticizable raw material batch mixture containing powdered silicon metal, a water soluble crosslinking thermoset resin, a powdered silicon-containing filler, a water soluble thermoplastic binder, and water into a green honeycomb body, and thereafter drying, curing and sintering the green body at a temperature sufficient to convert the green body to a porous silicon carbide sintered body.

Abstract: A resin transfer molding (RTM) process is disclosed for rapidly filling a fibrous preform and/or a rigid, porous body with high viscosity resin or pitch. The process is suitable for impregnated multiple porous bodies stacked in a single mold. The process uses a fibrous preform or rigid porous body which is placed into a mold matching the desired part geometry. A resin is injected into the mold at temperature and pressure. After cooling, the infiltrated component is removed from the mold. The mold is constructed from two halves fitted to form at least one mold cavity. A gate fitted with a nozzle is set into one of the mold halves, and a valve admits resin or pitch into the gate area. Venting or vacuum can be applied to the mold. The mold is held in a hydraulic press and an extruder, optionally fitted with an accumulator, supplies molten resin or pitch to the mold.

Abstract: This invention provides a pitch fiber bundle for carbon fibers of small size, a carbon fiber bundle, and a method for the production thereof, i.e. a method for the production of carbon fibers of a small size, a pitch fiber bundle, and a carbon fiber bundle at a lower cost with higher productivity than usual. The method for the production of pitch type carbon fibers according to this invention comprises dividing a plurality of pitch fibers into not less than two bundles, intertwining the bundles by exposure to currents of air thereby forming a first fiber bundle, binding a plurality of such first fiber bundles, and again intertwining the bound pitch fiber bundles by exposure to currents of air thereby forming a second fiber bundle.

Abstract: A process for producing solid, porous graphites which provides a more uniform density gradient throughout the ultimate product. The process utilizes a pressure drop during processing in order to induce boiling and varies the processing pressure between an initial pressure which exceeds 1000 psig and a final processing pressure which generally exceeds the initial pressure. The particular processing techniques employed allow additional viscosity manipulation as well as improved density gradient characteristics in the ultimate product. The final products have bulk thermal conductivities in the range from 90-300 W/mK with apparent densities ranging from about 0.678 g/cc-1.

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 method of making an adsorbent carbon fiber based monolith having improved methane gas storage capabilities is disclosed. Additionally, the monolithic nature of the storage carbon allows it to exhibit greater thermal conductivity than conventional granular activated carbon or powdered activated carbon storage beds. The storage of methane gas is achieved through the process of physical adsorption in the micropores that are developed in the structure of the adsorbent monolith. The disclosed monolith is capable of storing greater than 150 V/V of methane [i.e., >150 STP (101.325 KPa, 298K) volumes of methane per unit volume of storage vessel internal volume] at a pressure of 3.5 MPa (500 psi).

Abstract: A method for manufacturing carbon/silicon-carbide composite by a ‘One-shot’ process including carbonization, heat processing, infiltration, and forming an anti-oxidation layer on surface is provided through the steps of: 1) hardening a stacked carbon/phenolic preform; 2) carbonization and heat processing the preform until the temperature reaches at 2300° C.; 3) infiltrating and sintering the liquid metal silicon within the temperature of 1400˜1800° C.; and 4) inducting a compound including SiO2to gas phase and heat processing it while forming an anti-oxidation layer on the surface within temperature range of 2000° C.˜2700° C. (desirably, in the range of higher than 2300° C., and more desirably, at the temperature near 2500° C.). Herein, the carbonization, heat processing, and ultra-high heat processing might be performed at the same time in the step 2) and the step 4) might not be performed.

Abstract: There is provided a porous material suitable for use in a bearing retainer, having such properties as a small contraction ratio of the dimensions of a formed workpiece to those of a finished product, excellent hot oil resistance, small contraction change, insusceptibility to damage, light weight, a long service life, and ability to retain oil and grease for a long period of time. The porous material suitable for use in the bearing retainer is obtained by a process comprising the steps of mixing degreased bran derived from rice bran with a thermosetting resin before kneading, subjecting a kneaded mixture to a primary firing in an inert gas at a temperature in a range of 700 to 1000° C.

Abstract: An electrode for secondary battery made of carbon material is provided, which is light in weight while excellent in charge-discharge properties and in durability in repetitive use. A material for electrode is obtained by intermixing a synthetic resin with vapor-phase growth carbon fibers to make the vapor-phase growth carbon fibers uniformly dispersed in the synthetic resin to obtain a mixture, molding the mixture into a predetermined shape to obtain a molded product, and heating the molded product at high temperature to convert it into a carbon-carbon composite material. The electrode for battery is made of thus obtained carbon-carbon composite material.

Abstract: A method for monitoring characteristics of materials includes placing a material in an application zone, measuring a change in at least one property value of the application zone caused by placing the material in the application zone and relating changes in the property value of the application zone caused by the material to at least one characteristic of the material An apparatus for monitoring characteristics of a material includes a measuring device for measuring a property value resulting from applying a frequency signal to the application zone after placing a material in the application zone and a processor for relating changes in the property value caused by placement of the material in the application zone to at least one desired characteristic of the material. The application zone is preferably a resonant cavity.

Abstract: A method and apparatus for extruding pitch based foam is disclosed. The method includes the steps of: forming a viscous pitch foam; passing the precursor through an extrusion tube; and subjecting the precursor in said extrusion tube to a temperature gradient which varies along the length of the extrusion tube to form an extruded carbon foam. The apparatus includes an extrusion tube having a passageway communicatively connected to a chamber in which a viscous pitch foam formed in the chamber passes through the extrusion tube, and a heating mechanism in thermal communication with the tube for heating the viscous pitch foam along the length of the tube in accordance with a predetermined temperature gradient.

Abstract: A method of making carbon-carbon pistons and a limited variety of other products also requiring light weight, high strength and high thermal conductivity, and the resulting piston, including the steps of feeding impregnated fibers from spools into a layered bundle of fibers, coating the fibers with a carbonaceous material to form a preform, sleeving the preform with a thermoplastic sleeve, extruding the coated preform, passing the preform through an oven while compacting the preform further, and cutting the preform into standard lengths as the preform exits the furnace and achieves a degree of cool down. The pistons are machined from the cut preforms with the piston axis parallel to the fibers and layers. The pistons include crown, skirt, and wrist pin bosses and the axis of the wrist pin bosses is perpendicular to the fibers and layers.

Abstract: A method and apparatus for extruding pitch based foam is disclosed. The method includes the steps of: forming a viscous pitch foam; passing the precursor through an extrusion tube; and subjecting the precursor in said extrusion tube to a temperature gradient which varies along the length of the extrusion tube to form an extruded carbon foam. The apparatus includes an extrusion tube having a passageway communicatively connected to a chamber in which a viscous pitch foam formed in the chamber paring through the extrusion tube, and a heating mechanism in thermal communication with the tube for heating the viscous pitch foam along the length of the tube in accordance with a predetermined temperature gradient.

Abstract: To realize constituent elements for realizing a nonaqueous secondary battery having high energy density and high repeating stability, and a nonaqueous secondary battery using the same.

Abstract: Activated carbon filters containing transition metals, are prepared by (a) exchanging the transition metal with a cellulose ion exchange material to produce a cellulose material containing the transition metal; (b) charring of the product of (a); activating the product of (b) to form an activated carbon filter having a pore network throughout; and removing surface carbon substantially throughout the pore network of the filter formed in (c). Methods of filtering an atmosphere containing a gaseous contaminant by passing the contaminated atmosphere through a filter made by this process are described.

Abstract: A carbon-carbon composite material is made by providing an open-celled carbon foam preform, and densifying the preform with carbonaceous material. The open-celled carbon foam preform may be oxygen stabilized prior to carbonization, and the foam preform densified by CVD, HIP, PIC, VPI, pitch and resin injection, or any combination thereof. The carbon-carbon composite material can be heat treated to provide thermal management materials, structural materials, or a friction material for use in a brake or clutch mechanism.

Abstract: A method and apparatus for the carbonization of polyacrylonitrile (PAN) precursor fibers. The apparatus comprises a furnace, or series of furnaces in side-by-side arrangement. Each furnace includes a heater, an air inlet and an air diffusion plate. The fiber is located in the furnace above the air diffuser plate, such that heated air is evenly dispersed over the fibers. The method generally comprises the steps of heat treating the PAN precursor in an oxidizing environment to stabilize the fiber, and then further heat treating the stabilized fiber in an oxidizing environment to carbonize the stabilized fiber. The method can be carried out in a single furnace, or can be carried out in a series of furnaces in a continuous process.

Abstract: A process for preparing pins for connecting carbon electrodes is presented. In particular, a process for preparing pins for connecting carbon electrodes including the steps of combining calcined coke, a liquid pitch binder and carbon fibers derived from mesophase pitch to form a pinstock blend; extruding the pinstock blend to form a green pinstock; baking the green pinstock to form a carbonized pinstock; and graphitizing the carbonized pinstock by maintaining the carbonized pinstock at a temperature of at least about 2500° C. for no more than about 18 hours is presented. The pins prepared by the inventive process are also presented.

Abstract: Milled carbon fibers are provided which have a fiber cut surface and a fiber axis intersecting with each other at cross angles, the smaller one thereof being at least 65° on the average. The milled carbon fibers may have a specific surface area as measured by the BET method of 0.2 to 10 m2/g. The milled carbon fibers may be obtained by a process comprising melt spinning of mesophase pitch, infusibilization, milling of the infusibilized pitch fibers as obtained or after a primary heat treatment at low temperatures in an inert gas and a high-temperature heat treatment in an inert gas.

Abstract: A process for preparing pins for connecting carbon electrodes is presented. In particular, a process for preparing pins for connecting carbon electrodes including the steps of combining calcined coke, a liquid pitch binder and carbon fibers derived from mesophase pitch to form a pinstock blend; extruding the pinstock blend to form a green pinstock; baking the green pinstock to form a carbonized pinstock; and graphitizing the carbonized pinstock by maintaining the carbonized pinstock at a temperature of at least about 2500° C. for no more than about 18 hours is presented. The pins prepared by the inventive process are also presented.

Abstract: A process for producing carbon foam or a composite is disclosed which obviates the need for conventional oxidative stabilization. The process employs mesophase or isotropic pitch and a simplified process using a single mold. The foam has a relatively uniform distribution of pore sizes and a highly aligned graphic structure in the struts. The foam material can be made into a composite which is useful in high temperature sandwich panels for both thermal and structural applications.

Abstract: An activated carbon fiber composite for separation and purification, or catalytic processing of fluids is described. The activated composite comprises carbon fibers rigidly bonded to form an open, permeable, rigid monolith capable of being formed to near-net-shape. Separation and purification of gases are effected by means of a controlled pore structure that is developed in the carbon fibers contained in the composite. The open, permeable structure allows the free flow of gases through the monolith accompanied by high rates of adsorption. By modification of the pore structure and bulk density the composite can be rendered suitable for applications such as gas storage, catalysis, and liquid phase processing.

Abstract: A process for manufacturing a brake lining made of a fiber-reinforced ceramic C/SiC material includes (1) producing a carbon fiber body having at least one of a defined volume of pores and capillaries; (2) infiltrating the carbon fiber body with at least one of carbon or a carbon precursor; (3) pressing the infiltrated carbon fiber body, thereby forming a green compact; (4) pyrolyzing the green compact, thereby forming a porous C/C body; (5) adjusting at least one of a pore and a capillary volume of the porous C/C body to maximally approximately 60% by volume; and (6) infiltrating the C/C body with liquid silicon so that carbon, at least in an area of pores and capillaries which is close to the surface, becomes silicon carbide.

Abstract: A process for the production of carbon fibers, including melt-spinning mesophase pitch having an optically anisotropic content of at least 90%, a softening point of 190° C. to 280° C. and a heating weight loss of 0.7% by weight or less at a spinning temperature to form a spun fiber, infusibilizing the spun fiber to obtain an infusible fiber and carbonizing the infusible fiber.

Abstract: A composite material article reinforced with high strength short graphite fibers and having a matrix substantially consisting of silicon carbide is prepared which has an elongation at break of 0.25 to 0.5% and thus exhibits quasi-ductile failure behavior. The short reinforcing graphite fibers are enclosed by at least two shells of graphitized carbon which have been obtained by impregnation with carbonizable impregnating agents and subsequent carbonization. The shell closest to the graphite fibers contains no cracks. The outermost shell is partially converted into silicon carbide. The starting material used comprises long or short fiber prepregs, which are first carbonized, then subjected at least once to an operation consisting of impregnation with a carbonizable impregnating agent and recarbonization, then graphitized at a temperature of up to a maximum of 2400° C. and then comminuted to yield a dry material for the production of a precursor article.

Abstract: A process for producing a body having a porous matrix of at least one recrystallized ceramic material, or for producing a similar fiber-reinforced body, includes shaping a raw material batch which contains a raw material powder and then sintering. A raw material powder is used which has grain size distribution of a fine grain fraction of an average grain size of at most approximately 2 &mgr;m and a coarse grain fraction of an average grain size of approximately 1.5 &mgr;m to approximately 30 &mgr;m, and the sintering process is carried out at a temperature of at most approximately 1,800° C. Because of the selected grain sizes and grain size distributions, the sintering process can be carried out at lower temperatures. In particular, reinforcing fibers can be worked in which can withstand higher sintering temperatures. By defining the grain size of the powder, a porosity can also be set which permits a good impregnating with organic and/or inorganic substances.

Abstract: The resent invention provides a carbon fiber which enables a molded article produced from a fiber-reinforced composite material using the carbon fiber to exhibit excellent flexibility and to be freed from defects such as bending. According to the method of the present invention the carbon fiber is produced by a two-stage infusibilizing process, namely carrying out a first-stage infusibilization of a pitch-based fiber, which is obtained from mesophase pitch having a softening point of 200 to 400° C. and a true density of 1.30 to 1.38 g/cm3, in a mixed gas atmosphere having a nitrogen dioxide concentration of 1 to 5% by volume and an oxygen concentration of 5 to 50% by volume, the balance being an inert gas or steam, at a temperature between 100 and 200° C. and then carrying out a second-stage infusibilization of the product of the first-stage infusibilization in a mixed gas atmosphere having a nitrogen dioxide concentration of 0.