Abstract: It is an object of the present invention to provide a method for simply producing a high purity silicon carbide sintered body having no remaining metal silicon and excellent heat resistance. A method for producing a silicon carbide sintered body of the present invention comprises the steps of: preparing a slurry by dispersing silicon carbide powder in a solvent; forming a molded body by pouring the slurry into a mold and effecting calcination for the slurry in a vacuum atmosphere or in an inert gas atmosphere; and sealing pores within the calcined molded body by impregnating the pores with high purity metal silicon molten by heating, and allowing the high purity metal silicon and carbon contained in the molded body to react on each other in the pores so as to produce silicon carbide.

Abstract: The present invention provides a method of manufacturing an exfoliated graphite/phenol resin composite foam of a porosity of 50-95%, a density of 0.1-0.8 g/cm3, by forming under contact pressure or reduced pressure at a temperature of 140-200° C. a mixture comprising 100 parts by weight of powdered and/or crushed exfoliated graphite and 40-240 parts by weight of phenol resin; an exfoliated graphite/phenol resin composite foam obtained by the method; and a method of obtaining an exfoliated graphite/glassy carbon composite foam of a porosity of 50-95%, a density 0.1-0.8 g/cm3 with volumetric baking shrinkage of 10% or less by baking the exfoliated graphite/phenol resin composite foam.

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 process for producing graphitic foam comprises mixing a first amount of an activated first carbon precursor with a second amount of a second carbon precursor, heating the mixture of the activated first and the second carbon precursors to a temperature sufficient to coalesce the mixture into a liquid, foaming the mixture, heating the foam under an inert atmosphere to a temperature and for a length of time sufficient to carbonize the foam, and heating the carbonized foam under an inert atmosphere to a temperature and for a length of time sufficient to graphitize the foam.

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 process for producing molded pitch based foam is shown which provides a more uniform density gradient throughout the ultimate product. The process utilizes a pressure drop during processing in order to induce foaming. By inducing foaming through process depressurization, additional viscosity manipulation can be achieved as well as improved density gradient characteristics in the ultimate product.

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 a carbon foam heat sink 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. The foam is encased and filled with a phase change material to provide a very efficient heat sink device.

Abstract: A voltage nonlinear resistor is composed of an aggregate of silicon carbide particles doped with impurities, in which oxygen and at least one of aluminum and boron are diffused in the vicinity of the surfaces of the silicon carbide particles, the diffusion length of the oxygen is about 100 nm or less from the surfaces of the silicon carbide particles, and the diffusion length of at least one of the aluminum and the boron is in the range of about 5 to 100 nm from the surfaces of the silicon carbide particles. A method for fabricating a voltage nonlinear resistor and a varistor using a voltage nonlinear resistor are also disclosed.

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 process for producing molded pitch based foam is disclosed which minimizes cracking. The process includes forming a viscous pitch foam in a container, and then transferring the viscous pitch foam from the container into a mold. The viscous pitch foam in the mold is hardened to provide a carbon foam having a relatively uniform distribution of pore sizes and a highly aligned graphic structure in the struts.

Abstract: A polarizable electrode (1) comprises an activated carbon/carbon composite cosisting essentially of an activated carbon component and a carbon component. The activated carbon component comprises activated carbon powder or fiber. The carbon component is produced by carbonizing a thermosetting resin. The composite has a density within a range between 0.70 and 0.85 g/cm3, both inclusive, and a thickness within another range between 0.7 and 3.0 cm, both inclusive.

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: Activated carbon for use in an electric double layer capacitor is in the form of particles produced by crushing activated carbon or fibers of activated carbon. The particles have a surface covered at least partly with a laminated structure layer of graphite formed along the surface.

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 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: 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.