Flake Or Fibrous Constituent Or Fibrous Grain Structure Patents (Class 75/229)
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Patent number: 4463058Abstract: The invention features a method and resultant article of the method, wherein deagglomerated silicon carbide whiskers are uniformly dispersed and/or distributed in a matrix material, generally a metal. The uniform distribution achieved by the invention greatly enhances the mechanical properties of the composite, such as the ultimate strength. The method comprises the deagglomeration of silicon carbide whiskers prior to mixing with matrix materials.Type: GrantFiled: June 16, 1981Date of Patent: July 31, 1984Assignee: Atlantic Richfield CompanyInventors: Paul E. Hood, John O. Pickens
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Patent number: 4441927Abstract: An ingot-derived agglomerated tantalum powder composition comprising a select granular tantalum powder and including a critical proportion of a select flaked tantalum powder.Type: GrantFiled: November 16, 1982Date of Patent: April 10, 1984Assignee: Cabot CorporationInventors: Marlyn F. Getz, Michael J. Maggio, Billy F. Hitch
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Process for the surface treatment of inorganic fibers for reinforcing titanium or nickel and product
Patent number: 4440571Abstract: A process for the surface treatment of inorganic fibers for reinforcing titanium or nickel, comprising the steps of coating the surface of inorganic fibers with an aqueous or organic solvent solution containing a titanate, borate, tetralkylammonium hydroxide and, if desired, dextrin and then heat treating the coated fibers at a high temperature in an inert or non-oxidizing atmosphere. In one embodiment, the heat treated inorganic fibers is further subjected to ionic or chemical plating with nickel.Type: GrantFiled: July 6, 1982Date of Patent: April 3, 1984Assignee: Nippon Carbon Co., Ltd.Inventors: Toshikatsu Ishikawa, Junichi Tanaka, Haruo Teranishi, Tatsuya Okamura, Tokuji Hayase -
Patent number: 4415363Abstract: A composition of material for use as a friction lining with a cast iron mating surface. The friction lining has an iron powder base that reacts with tin to alloy and hold substantially equal weight percentages of graphite and coke in a fixed position. The friction lining has a substantially constant wear rate up to 300.degree. C. and a linear wear rate between 300.degree.-500.degree. C.Type: GrantFiled: May 3, 1982Date of Patent: November 15, 1983Assignee: The Bendix CorporationInventors: Keith E. Sanftleben, Walter R. Tarr
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Patent number: 4402744Abstract: An aluminum coated carbon article or composite, and process therefor having aluminum chemically bonded to carbon via an interface of a metal monocarbide formed in situ when an intermetallic phase comprising aluminum and a metal capable of reacting with carbon to form a metal carbide is reduced by carbon to aluminum and a metal carbide, the metal selected from the group consisting of tantalum, titanium and hafnium.Type: GrantFiled: August 29, 1980Date of Patent: September 6, 1983Assignee: Union Carbide CorporationInventor: Raymond V. Sara
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Patent number: 4377622Abstract: Filaments of glassy metallic alloys prepared by chill block melt-spinning are consolidated under heat and pressure by an extrusion process. Products obtainable by the process include discrete bodies of glassy metallic alloys of substantially uniform composition and articles having one or more layers of glassy metallic alloy clad onto one or more non-glassy metallic alloy substrates.Type: GrantFiled: August 25, 1980Date of Patent: March 22, 1983Assignee: General Electric CompanyInventor: Howard H. Liebermann
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Patent number: 4374059Abstract: An improved process for molding fiber-reinforced articles and in particular, those articles which are formed from monofilaments such as metal fibers and processed mineral fibers of the slag type. The fiber-containing molding composition is enclosed in a restraining means, such as a bag, and placed in a mold and formed during which time the bag advantageously deteriorates.Type: GrantFiled: May 11, 1981Date of Patent: February 15, 1983Assignee: Carlisle CorporationInventor: Harry H. Wagner
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Patent number: 4367159Abstract: A positive electrode for a secondary electrochemical cell wherein an electrically conductive current collector is in electrical contact with a particulate mixture of gray cast iron and an alkali metal sulfide and an electrolyte including alkali metal halides or alkaline earth metal halides. Also present may be a transition metal sulfide and graphite flakes from the conversion of gray cast iron to iron sulfide. Also disclosed is a method of distributing carbon flakes in a cell wherein there is formed an electrochemical cell of a positive electrode structure of the type described and a suitable electrolyte and a second electrode containing a material capable of alloying with alkali metal ions. The cell is connected to a source of electrical potential to electrochemically convert gray cast iron to an iron sulfide and uniformly to distribute carbon flakes formerly in the gray cast iron throughout the positive electrode while forming an alkali metal alloy in the negative electrode.Type: GrantFiled: January 19, 1981Date of Patent: January 4, 1983Assignee: The United States of America as represented by the United States Department of EnergyInventors: Franklin C. Mrazek, John A. Smaga, James E. Battles
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Patent number: 4354075Abstract: An electrical contact element is made of material which is resistant to metal migration and which contains a major proportion by weight, at least two metallic components which are soluble in each other and form a composite material. At least one of the components consists of a noble metal, and the metallic components are heterogeneously embedded in the composite material as pure metallic components. A process for making such a contact element comprises forming jacket wires, made of the metallic components, into clusters and metallurgically joining the wires by plastic shaping to form the composite material.Type: GrantFiled: October 1, 1980Date of Patent: October 12, 1982Assignee: G. RauInventors: Dieter Stockel, Hans H. Kocher
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Patent number: 4347083Abstract: An aluminum coated carbon article or composite, and process therefor having aluminum chemically bonded to carbon via an interface of a metal monocarbide formed in situ when an intermetallic phase comprising aluminum and a metal capable of reacting with carbon to form a metal carbide is reduced by carbon to aluminum and a metal carbide, the metal selected from the group consisting of tantalum, titanium and hafnium.Type: GrantFiled: August 29, 1980Date of Patent: August 31, 1982Assignee: Union Carbide CorporationInventor: Raymond V. Sara
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Patent number: 4314399Abstract: This invention relates to a method of producing a mold for use as a part of a tool for shaping of moldable material and having relatively high strength and heat resistance characteristics. According to the invention there is formed a porous body of sinterable material in contact with a pattern to form a material shaping surface on the body; the body when still in contact with the pattern surface is sintered and the sintered body is at least partially filled with infiltrating material having a melting point lower than that of the sintered body. The infiltrating step is effected in such matter that the pores of the surface of the sintered body in contact with the pattern surface are filled by infiltrating material from the side of the body opposite to the pattern surface whereby also the infiltrating material which fills the pores of the sintered body in the surface thereof is formed by the pattern surface.Type: GrantFiled: January 24, 1977Date of Patent: February 9, 1982Inventor: Lars M. Severinsson
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Patent number: 4295885Abstract: Material and method for securely attaching boron filaments to other like filaments and to a substrate with preservation of the filament integrity for cutting and abrading by coating them with a mixture of matrix metals essentially containing copper, tin and titanium and joining the filaments by the matrix metals and/or to the substrate into an integral structure by liquid-phase-sintering of the matrix metals which grip and adhere the filaments in a strong, tough alloy with the integrity of the filaments essentially preserved. Boron filament-containing tools for cutting, grinding, abrading, or the like may be fabricated using the materials of the invention and the methods disclosed.Type: GrantFiled: September 11, 1978Date of Patent: October 20, 1981Assignee: General Dynamics CorporationInventor: William T. Kaarlela
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Patent number: 4293450Abstract: An electrically conductive composition is provided which comprises an intercalation compound of (1) graphite, (2) fluorosulfonic acid, chlorosulfonic acid, or mixtures thereof, and (3) a boron trihalide, a tetrahalide of a Group IV element, a pentahalide of a Group V element, or mixtures thereof. The graphite may be in any one of a variety of physical configurations, e.g. as particulate crystals or present in a carbonaceous fibrous material, at the time of the intercalation reaction. The resulting graphite intercalation compound possesses advantageous electrical conductivity characteristics not possessed by plain graphite and is capable of utilization as a light weight electrical conductor. The graphite intercalation compound may optionally be provided within a metal matrix (e.g. within elemental copper) to form an electrically conductive composite article.Type: GrantFiled: April 18, 1978Date of Patent: October 6, 1981Inventor: F. Lincoln Vogel
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Patent number: 4289833Abstract: A liquid phase sintered body for brazed joints having a multiplicity of pores, grooves and/or indented patterns formed on a desired surface. The liquid phase sintered body is produced by a method comprising the steps of forming a compact body of a mixture of a hard refractory material, such as carbides, nitrides, oxides, borides and silicides mixed with cementing metal in powder form, placing on the desired surface any one of coarse grains, strands or plates of a metal having a diameter or a thickness over ten times as great as the grain size of the cementing metal, and sintering the compact body under conditions suitable for melting the coarse grains, strands and/or mesh of strands or plates after densification of the compact body has been completed or substantially completed. The metal forming the coarse grains, strands or plates must have a melting point which is more than 50.degree. C.Type: GrantFiled: March 19, 1979Date of Patent: September 15, 1981Assignee: Kabushiki Kaisha Fujikoshi t/a Nachi-Fujikoshi Corp.Inventor: Takeji Hachisuka
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Patent number: 4278729Abstract: Carbon fiber reinforced tantalum carbide composites are produced by vacuum infiltration of omni-weave carbon, e.g. three dimensional graphite, yarn preforms with an aqueous saturated solution containing tantalum fluoride and sucrose. Anhydrous ammonia is added under pressure, forming ammonium fluoride, which is removed by vacuum sublimation by application of heat. The resulting preform containing tantalum pentoxide and partially pyrolyzed sucrose is heated at high temperature and reduced pressure to decompose the sucrose to yield active carbon which reacts with the tantalum pentoxide to yield tantalum carbide and carbon monoxide.Type: GrantFiled: November 19, 1979Date of Patent: July 14, 1981Inventors: James O. Gibson, Mark G. Gibson
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Patent number: 4259112Abstract: Composite materials are prepared by mixing metal powder and dissimilar reinforcement materials in a fluid binder to form a slurry. The slurry is spread to form thin sheets which are air dried. The sheets are stacked to a predetermined thickness and placed in a vacuum retort where binder is removed at elevated temperature and reduced pressure. The resulting composite material is consolidated and bonded at elevated temperature and pressure.Type: GrantFiled: April 5, 1979Date of Patent: March 31, 1981Assignee: DWA Composite Specialties, Inc.Inventors: Joseph F. Dolowy, Jr., Bradley A. Webb, Edward C. Supan
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Patent number: 4236925Abstract: A method of producing a sintered material having a high wearing resistance and damping capacity by mixing 5-30 wt. % of a powdery metal selected from the group consisting of lead, magnesium and graphite with the remainder of a powdery metal selected from the group consisting of iron, copper, aluminum, cast iron and alloys thereof, compression-molding the mixture, subjecting the same to plastic treatment and sintering the same by heating to a temperature above a recrystallization point of the matrix metal, and the sintered material thus produced.Type: GrantFiled: August 10, 1978Date of Patent: December 2, 1980Assignee: Hitachi, Ltd.Inventors: Jin Onuke, Masateru Suwa, Ko Soeno, Akio Okayama, Masatoshi Tsuchiya, Hisakiti Onodera
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Patent number: 4217399Abstract: Novel bi-metallic filamentary composites are produced by first forming a conjugate precursor filament comprised of an organic polymer together with particles of a first reducible metal oxide and particles of a second reducible metal oxide with the metal component of each of the two metal oxides being sinterable at a temperature which is below the melting point of the other. The structure of the precursor is characterized by a first longitudinally extending layer along its length which contains the particles of the first reducible metal oxide, and an adhering second essentially distinct longitudinally extending layer extending along its length which contains the particles of the second reducible metal oxide. The essentially discrete layers may be in a sheath-core arrangement or in side-by-side relationship.Type: GrantFiled: February 13, 1978Date of Patent: August 12, 1980Assignee: Monsanto CompanyInventor: Emerick J. Dobo
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Patent number: 4180399Abstract: Molybdenum base composite materials having high tensile strength and oxidon resistance at high temperatures are produced by piling in parallel and embedding silicon carbide fibers containing 0.01-20% by weight of free carbon, which have been produced by the specific method already disclosed in U.S. patent application Ser. No. 677,960, in molybdenum base metallic powders and by compressing and sintering the assembly.Type: GrantFiled: September 19, 1977Date of Patent: December 25, 1979Assignee: The Foundation: The Research Institute for Special Inorganic MaterialsInventors: Chiaki Asada, Makoto Saito, Hisashi Kajima
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Patent number: 4175918Abstract: An elongate consolidated article for treating molten metal has a multiplicity of elongate fibers embedded within a coherent matrix of treating agent.Type: GrantFiled: December 12, 1977Date of Patent: November 27, 1979Assignee: Caterpillar Tractor Co.Inventor: John G. Frantzreb, Sr.
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Patent number: 4147538Abstract: Cobalt or cobalt alloy composite materials reinforced with continuous silicon carbide fibers, which have a high tensile strength, a low elongation, a high Young modulus and a high tensile strength at a high temperature, are produced by filling spaces in piles of the continuous silicon carbide fibers containing 0.01%-30% by weight of free carbon with melted or powdery metallic cobalt or cobalt alloy and integrating the said fibers with the said metal.Type: GrantFiled: January 21, 1977Date of Patent: April 3, 1979Assignee: The Research Institute for Iron, Steel and other Metals of the Tohoku UniversityInventors: Seishi Yajima, Hideo Kayano, Chiaki Asada, Makoto Saito
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Patent number: 4141726Abstract: Beryllium composite material reinforced with continuous silicon carbide fibers is obtained by bonding tightly continuous silicon carbide fibers obtained by baking spun fibers of organosilicon high molecular weight compound, with beryllium and its alloys as a matrix. The silicon carbide fiber-beryllium composite material is excellent in the mechanical strength, heat resistance and oxidation resistance, and is useful as a material for aerospace instrument and a material for nuclear industry.Type: GrantFiled: April 4, 1977Date of Patent: February 27, 1979Assignee: The Research Institute for Iron, Steel and Other Metals of the Tohoku UniversityInventors: Seishi Yajima, Masaaki Hamano
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Patent number: 4139376Abstract: An abradable seal material suitable for high temperature application in turbomachinery comprising a sintered mat of (1) randomly disposed fine metal fibers, or (2) fine metal powders or (3) both fibers and powders. The metal fiber and powder are composed of an alloy consisting essentially of I, Al, Cr, II, or I, Al, Cr, III, wherein I is at least one member of the group Fe, Co, Ni, and Co plus Ni, II is a member of the group consisting of Y, Sc and Rare Earths, and III is at least one member of the group consisting of Si, Hf, Zr, Cb, and Ta. The exposed surfaces of the fibers and powder forming the seal are protected against oxidation at high temperatures by a coating of Al.sub.2 O.sub.3 which is formed on the substrate. Said substrate has an Al content of at least 4% to replace spalled Al.sub.2 O.sub.3 and for "healing" any Al.sub.2 O.sub.3 scale fractures.Type: GrantFiled: November 2, 1976Date of Patent: February 13, 1979Assignee: Brunswick CorporationInventors: Arnold R. Erickson, Carlino Panzera
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Patent number: 4134759Abstract: Light metal composite materials reinforced with novel continuous silicon carbide fibers composed of aluminum, aluminum alloy or magnesium alloy matrix and the continuous silicon carbide fibers containing 0.01-40% by weight of free carbon, in which the free carbon is reacted with aluminum or added metal elements in the aluminum alloy or magnesium alloy to form carbides. When the silicon carbide fibers are coated with a metal or ceramics, the wettability of the silicon carbide fibers to said matrix is more improved.Type: GrantFiled: December 13, 1976Date of Patent: January 16, 1979Assignee: The Research Institute for Iron, Steel and Other Metals of the Tohoku UniversityInventors: Seishi Yajima, Josaburo Hayashi, Mamoru Omori, Hideo Kayano
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Patent number: 4117565Abstract: Chromium base alloy composite materials having high corrosion resistance, idation resistance and tensile strength at high temperatures are produced by laminating and arranging silicon carbide fibers containing 0.01-20% by weight of free carbon, which have been produced by the specific method already disclosed in U.S. patent application Ser. No. 677,960, in volume fraction of 2-50% in chromium base alloy and by compressing and sintering the assembly.Type: GrantFiled: August 23, 1977Date of Patent: October 3, 1978Assignee: The Foundation: The Research Institute For Special Inorganic MaterialsInventors: Chiaki Asada, Katsushi Kusaka, Hisashi Kajima
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Patent number: 4118225Abstract: A method is disclosed for making fibrous steel webs or matts from particulate iron oxides with the aid of a fiber-forming acrylic polymer. A plurality of continuous filaments are first formed by wet spinning an acrylic polymer spin dope in which particles of iron oxide are dispersed. The filaments obtained are then converted into a precursor web or matt by conventional textile procedures. This is followed by exposing the precursor to a reducing atmosphere (e.g., a gaseous mixture of hydrogen and carbon monoxide) at a temperature in the range of from about 900.degree. C to 1150.degree. C for a period of about 3 to 8 minutes. Under these conditions, the iron oxide particles are reduced to the metallic state and the polymer in the precursor is pyrolized to carbon and by-product gases. The carbon in the system diffuses into the resulting iron, and the individual metal particles sinter to form a matt of steel wire having a configuration essentially corresponding to that of the precursor.Type: GrantFiled: October 28, 1975Date of Patent: October 3, 1978Assignee: Monsanto CompanyInventor: Emerick J. Dobo
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Patent number: 4116689Abstract: Material and method for securely attaching boron filaments to other like filaments and to a substrate with preservation of the filament integrity for cutting and abrading by coating them with a mixture of matrix metals essentially containing copper, tin and titanium and joining the filaments by the matrix metals and/or to the substrate into an integral structure by liquid-phase-sintering of the matrix metals which grip and adhere the filaments in a strong, tough alloy with the integrity of the filaments essentially preserved. Boron-filament-containing tools for cutting, grinding, abrading, or the like may be fabricated using the materials of the invention and the methods disclosed.Type: GrantFiled: December 24, 1975Date of Patent: September 26, 1978Assignee: General Dynamics CorporationInventor: William Thomas Kaarlela
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Patent number: 4116688Abstract: Method and material for fabricating composite structures and cutting tools containing super hard filaments using a modified brazing process that employs liquid phase sintering to alloy a mixture of metals about groups of the filaments in side by side parallelized arrangement to produce preforms or bundles of the filaments secured spaced apart in a strong tough metal matrix. A plurality of the completed bundles may then be bonded together by like method and materials into larger structures, tools or cutting portions thereof.Type: GrantFiled: December 24, 1975Date of Patent: September 26, 1978Assignee: General Dynamics CorporationInventor: William Thomas Kaarlela
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Patent number: 4104445Abstract: A method for making filamentary steel wire from particulate iron oxides with the aid of a fiber-forming acrylic polymer is disclosed. A precursor filament is first formed by wet-spinning an acrylic polymer spin dope in which particles of iron oxide are dispersed. The resulting precursor filament is then exposed to a reducing atmosphere (e.g., a gaseous mixture of hydrogen and carbon monoxide) at a temperature in the range of from about 900.degree. C. to 1150.degree. C. for a period of about 3 to 8 minutes. Under these conditions, the iron oxide particles are reduced to the metallic state and the polymer in the precursor is pyrolized to carbon and byproduct gases. The carbon diffuses into the resulting metallic iron, and the individual metal particles sinter to form continuous steel wire.The method has the capability of producing steel wire of an essentially ferritic/pearlitic structure with a tensile property in excess of 140,000 psi.Type: GrantFiled: October 20, 1975Date of Patent: August 1, 1978Assignee: Monsanto CompanyInventor: Emerick J. Dobo
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Patent number: 4094673Abstract: An abradable seal material suitable for high temperature application in turbomachinery comprising a sintered mat of (1) randomly disposed fine metal fibers, or (2) fine metal powders or (3) both fibers and powders. The metal fiber and powder are composed of an alloy consisting essentially of I, Al, Cr, II, or I, Al, Cr, III, wherein I is at least one member of the group Fe, Co, Ni, and Co plus Ni, II is a member of the group consisting of Y, Sc and Rare Earths, and III is at least one member of the group consisting of Si, Hf, Zr, Cb, and Ta. The exposed surfaces of the fibers and powder forming the seal are protected against oxidation at high temperatures by a coating of Al.sub.2 O.sub.3 which is formed on the substrate. Said substrate has an Al content of at least 4% to replace spalled Al.sub.2 O.sub.3 and for "healing" any Al.sub.2 O.sub.3 scale fractures.Type: GrantFiled: November 2, 1976Date of Patent: June 13, 1978Assignee: Brunswick CorporationInventors: Arnold Roderick Erickson, Carlino Panzera
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Patent number: 4083719Abstract: Copper powder, carbon fibers arranged in random directions and a metal capable of reacting with carbon fibers are homogeneously mixed together, and the mixture is heated and molded under high pressure to form an integral composite. The so formed carbon fiber-copper matrix composite has no directional characteristic in mechanical properties, and the linear thermal expansion coefficient of the composite is low and the thermal stability of the composite is so high that when it is exposed to high temperature, no damage by thermal deformation is caused.Type: GrantFiled: October 29, 1976Date of Patent: April 11, 1978Assignee: Hitachi, Ltd.Inventors: Hideo Arakawa, Keiichi Kuniya, Takashi Namekawa, Tomio Iizuka
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Patent number: 4080204Abstract: Abradable seals for compressors and turbines are made of fibers and powders of an alloy consisting essentially of iron, nickel, chromium, aluminum, and yttrium. The alloy preferably contains 22-27 weight percent nickel, 18-22 weight percent chromium, 9-15 weight percent aluminum, 0.0005-0.05 weight percent yttrium, with the balance iron. Heat treatment of the alloy provides an aluminum rich phase which is uniformly dispersed throughout the alloy.Type: GrantFiled: March 29, 1976Date of Patent: March 21, 1978Assignee: Brunswick CorporationInventor: Carlino Panzera
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Patent number: 4072516Abstract: A novel graphite fiber/metal composite material in which the graphite fibers have an adherent coating of silicon oxide and silicon carbide. The coating protects the graphite surface from attack by carbide forming matrix metals such as aluminum, titanium, magnesium and nickel. In a preferred embodiment of the invention the coating is formed by an intermediate temperature vapor deposition technique involving the reduction of silicon tetrachloride in the presence of hydrogen and an oxygen containing gas.Type: GrantFiled: September 15, 1975Date of Patent: February 7, 1978Assignee: Fiber Materials, Inc.Inventors: Roger T. Pepper, Thomas A. Zack
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Patent number: 4067742Abstract: Ceramic tantalum carbide artifacts having high thermal shock and mechanical erosion resistance are provided by incorporating tungsten-rhenium and carbon particles in a tantalum carbide matrix. The mix is sintered by hot pressing to form the ceramic article which has a high fracture strength relative to its elastic modulus and thus has an improved thermal shock and mechanical erosion resistance. The tantalum carbide is preferable less than minus 100 mesh, the carbon particles are preferable less than minus 100 mesh, and the tungsten-rhenium particles are preferable elongate, having a length to thickness ratio of at least 2/1. Tungsten-rhenium wire pieces are suitable as well as graphite particles.Type: GrantFiled: April 1, 1976Date of Patent: January 10, 1978Inventors: James C. Administrator of the National Aeronautics and Space Administration, with respect to an invention of Fletcher, Leroy Honeycutt, III, Charles R. Manning, Jr.
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Patent number: 4066450Abstract: A metal body having a very large surface area and high porosity, useful as a gasoline vaporizer, a heat exchanger for automobiles, a catalyst or catalyst carrier, a filter, or the like, and composed of a plurality of metal fibers which are entangled with one another to form a bed or stratum, the metal fibers being coated with a metal in such manner that the stratum provides rough and complex surfaces with cracks and irregularities. The invention also includes a process for making said metal body including the steps of entangling metal fibers to form a bed, placing the bed of fibers in contact with a coating metal, heating the fiber bed and coating metal so as to wet the fibers with molten coating metal, and cooling.Type: GrantFiled: November 24, 1975Date of Patent: January 3, 1978Assignee: Kabushiki Kaisha Toyota Cho KenkyushoInventors: Masaharu Takeuchi, Isemi Igarashi, Tsuchio Bunda
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Patent number: 4060413Abstract: Composite turbine blades and vanes have been proposed in the past formed from nickel or cobalt base superalloys and reinforcing fibres such as tungsten, molybdenum, silicon carbide, or graphite. One of the problems has been the spacing of the fibres and arrangement within the form. The present invention provides for such arrangement by means of aligning the fibres on an alloy powder tape or cloth comprising powdered superalloy and an organic binder. Pieces of the tape are then cut in the desired shape and arranged within a mold and subsequently bonded into a consolidated shape.Type: GrantFiled: June 11, 1976Date of Patent: November 29, 1977Assignee: Westinghouse Canada LimitedInventors: Peter J. Mazzei, Gerrit VanDrunen