Patent application number | Description | Published |
20080251959 | Method of manufacturing a carbon-carbon brake disc - A method of manufacturing a carbon-carbon brake disc uses a restraint fixture ( | 10-16-2008 |
20080277824 | Pitch infiltration of carbon fiber preforms under high pressure - Process of manufacturing carbon-carbon composite preform by: (i.) arranging batch of carbon fiber preforms in infiltration vessel; (ii.) flooding vessel with hot liquid phase pitch at atmospheric pressure in inert atmosphere; (iii.) raising pressure in infiltration vessel to elevated pressure, and then slowly lowering pressure; and (iv.) repeating step (iii.). An apparatus that may be used is a heated infiltration vessel capable of operating at pressures above 100 psi, possible equipped with means to circulate heated pitch inside the vessel, in order to facilitate heat transfer into the carbon fiber preforms being infiltrated by the pitch. The need for a vacuum pump is eliminated, and the time spent heating the preform is substantially reduced. Instead of vacuum, cycled high pressure is employed to infiltrate carbon fiber preforms with pitch. The use of preheated pitch as a heat transfer agent avoids the slow transfer of heat into the preform prior to infiltration. | 11-13-2008 |
20090139807 | Brake assembly having multi-piece core and replaceable friction surfaces - A brake disk ( | 06-04-2009 |
20090148699 | CARBON FIBER CONTAINING CERAMIC PARTICLES - Small ceramic particles (e.g., of TiC) are incorporated into fibers. The ceramic particles enhance the friction and/or wear properties of a carbon-carbon composite article made with the impregnated or coated fibers. The impregnated fibers can be, e.g., polyacrylonitrile (PAN) fibers, pitch fibers, and other such fibers as are commonly employed in the manufacture of C—C friction materials. The impregnated fibers can be used to make woven, nonwoven, or random fiber preforms or in other known preform types. Preferred products are brake discs and other components of braking systems. The particles may be included in the fibers by mixing them with the resin employed to make the fibers and/or by applying them to the surfaces of the fibers in a binder. | 06-11-2009 |
20090236763 | Resin transfer molding to toughen composite beam keys - Method of manufacturing composite wheel beam key by: forming entirely from carbon fiber precursors or from carbon fiber precursors and ceramic materials a fibrous preform blank in a shape of a desired wheel beam key, wherein the fiber volume fraction of the preform blank is at least 50%; carbonizing the carbon fiber precursors; rigidifying the carbonized preform blank by subjecting it to at least one cycle of CVD; grinding the surface of the preform blank to open pores on its surface; and subjecting the open-pored preform blank to RTM processing with pitch. Also, carbon-carbon composite or carbon-ceramic composite wheel beam key produced by this process, having a density of from 1.5 g/cc to 2.1 g/cc and a maximum internal porosity of 10% or less. | 09-24-2009 |
20100000070 | Reusable core carbon-carbon composite brake disc - Method of manufacturing carbon-carbon composite brake disc comprising a dense reusable core. Preferably, the reusable core has a density of 1.8-2.05 g/cc. The method includes: forming a dense carbon-carbon composite core; positioning the dense core in a location within a carbon-carbon composite brake disc; and fixing the dense carbon-carbon composite core in place in its location within the carbon-carbon composite brake disc. It is economically advantageous to recover the dense core from a worn brake disc prior to positioning it in the brake disc. Also, an annular carbon-carbon composite brake disc made up of a friction surface containing 15-75 weight-% carbon-containing fibers and 25-85 weight-% resin binder and a dense carbon-carbon composite core comprising 40-75 weight-% carbon-containing fibers and 25-60 weight-% resin binder. | 01-07-2010 |
20100078839 | Pitch densification of carbon fiber preforms - A pitch densification process which is widely applicable in the densification of carbon fiber preforms and stabilized pitch fiber preforms. The process includes: (a.) introducing liquid pitch into a fibrous carbon preform; (b.) carbonizing the pitch-impregnated preform by heating it in the absence of oxidizing agents; and subsequently (c.) further densifying the carbonized pitch-impregnated preform. The pitch used for densification may be coal tar pitch, petroleum pitch, or synthetic pitch. The softening point of the pitch will normally range from 100° C. to 340° C., depending upon the properties to be imparted to the finished product. | 04-01-2010 |
20100084075 | Strength enhancement of carbon-carbon composite brake pads using fiber pre-stressing - This invention relates to an improved carbon-carbon composite material and method of preparation. The carbon-carbon composite material comprises a plurality of carbon fiber substrates that have been joined or consolidated. In the present invention, the carbon fibers are stressed during the preparation of the composite material. The invention comprises adding a low-melting point pitch to the carbon fiber substrates and heat treating the carbon fiber substrates. The fibers tend to shrink more than the pitch during heat-treatment which produces stress in the fibers. This invention enhances the strength of the composite material and improves reliability. | 04-08-2010 |
20110155323 | BONDING CARBON-CARBON COMPOSITES THROUGH A REACTANT LAYER - An apparatus for bonding a first carbon composite to a second carbon composite through a reactant layer includes a housing, and a pair of conductive press plates electrically isolated from the housing. The press plates are adapted to position the two parts to be bonded with a reactant layer therebetween. The press plates are subjected to an electrical potential and a clamping force, sufficient to initiate a combustion reaction that creates a molten ceramic to bond together the carbon-carbon composites. | 06-30-2011 |
20110180946 | TITANIUM CARBIDE AS A FRICTION AND WEAR MODIFIER IN FRICTION MATERIALS - Methods of making a carbon-carbon composite preforms, particularly suitable as brake discs in aircraft landing systems, by combining titanium carbide particles ranging in size from 0.01 to 10 microns in diameter, resinous binder, and carbon fibers or carbon fiber precursors in a mold, and subsequently subjecting the combined components to pressure and heat to carbonize the resinous binder by methods, thereby providing the carbon-carbon composite preform having particulate titanium carbide uniformly distributed throughout its mass. Prior to combining the titanium carbide and the binder with the fibers in this process, the particulate titanium carbide may be mixed with liquid binder, the resulting TiC/binder mixture may then solidified, and the resulting solid TiC/binder mixture may be ground into a fine powder for use in the process. Also, compositions for preparing a carbon-carbon composite friction materials, and methods of improving wear and dynamic stability in a carbon-carbon composite brake discs. | 07-28-2011 |
20140054818 | CORRUGATED CARBON FIBER PREFORM - In one example, a method includes mixing a plurality of carbon fibers in a liquid carrier to form a mixture, depositing the carbon fiber mixture in a layer, forming a plurality of corrugations in the carbon fiber layer, and rigidifying the corrugated carbon fiber layer to form a corrugated carbon fiber preform. In another example, a method includes substantially aligning a first ridge on a first surface of a first corrugated carbon fiber preform and a first groove on a first surface of a second corrugated carbon fiber preform, bringing the first surface of the first corrugated carbon fiber preform into contact with the first surface of the second corrugated carbon fiber preform, and densifying the first corrugated carbon fiber preform and the second carbon fiber preform to bond the first corrugated carbon fiber preform and the second carbon fiber preform. | 02-27-2014 |
20150031522 | CARBON-CARBON COMPOSITES INCLUDING ISOTROPIC CARBON ENCAPSULATING LAYER AND METHODS OF FORMING THE SAME - A technique of forming a carbon-carbon composite material includes infusing a liquid carbonizable precursor into a porous preform, and the infused precursor is subsequently pyrolyzed to convert the precursor to isotropic carbon. The preform then can be densified with a densifying agent, followed by infusion of the liquid carbonizable precursor into the densified preform. In some examples, after pyrolyzing the liquid carbonizable precursor, isotropic carbon extends substantially throughout a volume of the carbon-carbon composite material. | 01-29-2015 |
20150034432 | PREVENTING CARBON AO MIGRATION BY LIMITING SURFACE POROSITY - In the manufacture of carbon-carbon composite brake discs, migration of anti-oxidant substances into the friction surfaces is prevented by limiting or eliminating surface porosity in the carbon-carbon composite brake materials. The method includes infusing a suitable resin into pores in surface layers of the carbon-carbon composite disc and then charring the resin-infused disc to convert the resin in the pores to pyrolytic carbon. The resin may be infused into the carbon disc by submerging the disc in a molten resin. Prior to submerging the disc in the molten resin, the disc may subjected to a vacuum to remove air from the pores. While the disc is submerged in the molten resin, the pressure in the pressurizable vessel may increased to force the molten resin into the open porosity of the disc. | 02-05-2015 |