Sintering Or Heat Fusing Particles Patents (Class 264/125)
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Patent number: 4957884Abstract: A powder composition consisting essentially of an intimate mixture of boron carbide and titanium diboride, the mixture having an average particle size of less than about 0.5 micron, the particles being uniformaly dispersed such that elemental analytical techniques show all discrete concentrations of boron carbide and titanium diboride to be less than or equal to about 0.5 micron in diameter, is disclosed. The powder is useful for making a densified ceramic composition comprising titanium diboride grains, having an average grain size of less than or equal to about 3 microns in diameter, uniformly dispersed with boron carbide grains, having an average grain size of less than about 5 microns in diameter. The densified composition exhibits improved hardness and toughness when compared with titanium diboride or boron carbide compositions.Type: GrantFiled: April 15, 1988Date of Patent: September 18, 1990Assignee: The Dow Chemical CompanyInventors: Arne K. Knudsen, William Rafaniello
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Patent number: 4954314Abstract: A plural number of types of material powders are accommodated in an accommodation chamber in a mixed state and the material powders are continuously subjected to a self-exothermic reaction inducing chemical reactions between the material powders caused by heat of reaction released when the mixed material powders synthesize. The synthesized material of high temperature due to the self-exothermic reaction is pressed by utilizing an electromagnetic force just after the finish of the self-exothermic reaction. The exothermic reaction is caused by an ignition circuit including an ignition electrode and the electromagnetic force is generated by an electromagnetic force generation circuit including an electric current inducing means. These circuits are connected through and regulated by a relay circuit. Thus the synthetic products of fine structure are obtained.Type: GrantFiled: February 7, 1990Date of Patent: September 4, 1990Assignee: Kawasaki Jukogyo Kabushiki KaishaInventors: Yukio Nishiyama, Junzo Fujioka, Haruki Hino, Yuji Matsuzaki, Masayuki Sakiyama, Minoru Yokoyama
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Patent number: 4952554Abstract: A method of producing normal-metal-clad superconductive oxide wire, tape and the like is disclosed. The method comprises forming an intermediate body by surrounding a quantity of the oxide powder (e.g., Ba.sub.2 YCu.sub.3 O.sub.6.9) with an appropriate normal metal jacket, reducing the cross section of the intermediate body by any appropriate technique (e.g., drawing or rolling), and heat treating the elongated body such that substantial sintering of the powder results, and such that, after completion of the heat treatment, the sintered oxide has a composition that is associated with superconductivity in unclad bulk samples of the oxide. The latter condition requires that at least the portion of the cladding that is in contact with the oxide powder is substantially inert with respect to oxygen and the oxide under the conditions of the heat treatment. Silver is the currently preferred inert normal metal. Exemplarily, Ag can be used to provide a diffusion barrier with other normal metal (e.g.Type: GrantFiled: April 6, 1987Date of Patent: August 28, 1990Assignee: AT&T Bell LaboratoriesInventors: Sungho Jin, Richard C. Sherwood, Robert B. van Dover
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Patent number: 4952353Abstract: A process for densifying porous articles comprises providing a non-reactive container with a green article and sufficient solid encapsulating agent selected from the group consisting of tin and the tin-magnesium eutectic to encapsulate the green article when the agent is in the molten state. The temperature is raised sufficiently to melt the agent and to encapsulate the article. The encapsulated article is maintained at a pressure below the infiltrating pressure of the green article while heating the encapsulated article sufficiently to create a surface on the article that is essentially free of porosity and thereafter, the pressure on the encapsulated article is increased while maintaining the article at its sintering temperature for a sufficient time to increase the density of said article to at least about 98% of theoretical.Type: GrantFiled: December 28, 1989Date of Patent: August 28, 1990Assignee: GTE Laboratories IncorporatedInventor: Jeffrey T. Neil
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Patent number: 4944905Abstract: Process for making particulate ceramics having an alumina rich region near their surface, comprising the following steps:(a) mixing and pelletizing, with the aid of water, raw materials including a mineral particulate such as nepheline syenite and a binder such as bentonite;(b) drying the wet pellets from step (a);(c) mixing the dried pellets with alumina parting agent; and(d) firing the mixture of pellets and parting agent at a sufficient temperature (less than 1450.degree. C.) and for sufficient time for vitrification to occur.Type: GrantFiled: January 21, 1986Date of Patent: July 31, 1990Assignee: Minnesota Mining and Manufacturing CompanyInventors: James L. Gibb, James A. Laird, George W. Lee, William C. Whitcomb
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Patent number: 4944817Abstract: A method and apparatus for selectively sintering a layer of powder to produce a part comprising a plurality of sintered layers. The apparatus includes a computer controlling a laser to direct the laser energy onto the powder to produce a sintered mass. The computer either determines or is programmed with the boundaries of the desired cross-sectional regions of the part. For each cross-section, the aim of the laser beam is scanned over a layer of powder and the beam is switched on to sinter only the powder within the boundaries of the cross-section. Powder is applied and successive layers sintered until a completed part is formed. Preferably, the powder comprises a plurality of materials having different dissociation or bonding temperatures. The powder preferably comprises blended or coated materials.Type: GrantFiled: September 5, 1989Date of Patent: July 31, 1990Assignee: Board of Regents, The University of Texas SystemInventors: David L. Bourell, Harris L. Marcus, Joel W. Barlow, Joseph J. Beaman, Carl R. Deckard
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Patent number: 4943320Abstract: A process for preparing ceramic-metal composites without melting the metal is disclosed. A compact or green body is made from a ceramic and a metal, and the compact is sealed in a vacuum in a container such as a glass envelope. The compact is then heated to a temperature below the melting point of the metal, but high enough so that the vapor pressure of the metal is significant, and the metal redistributes through the ceramic by evaporation and condensation. The composite thereby forms a body having ceramic particles uniformly coated by the metal. Products formed by the process and fabrication of a B.sub.4 C/Cr composite are also disclosed.Type: GrantFiled: December 15, 1988Date of Patent: July 24, 1990Assignee: The Regents of the University of CaliforniaInventors: Alexander Pechnik, M. Dean Matthews
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Patent number: 4938816Abstract: A method and apparatus for selectively sintering a layer of powder to produce a part comprising a plurality of sintered layers. The apparatus includes a computer controlling a laser to direct the laser energy onto the powder to produce a sintered mass. The computer either determines or is programmed with the boundaries of the desired cross-sectional regions of the part. For each cross-section, the aim of the laser beam is scanned over a layer of powder and the beam is switched on to sinter only the powder within the boundaries of the cross-section. Powder is applied and successive layers sintered until a completed part is formed. Preferably, the powder is deposited to the target area of the laser and attains high bulk density during sintering.Type: GrantFiled: September 5, 1989Date of Patent: July 3, 1990Assignee: Board of Regents, The University of Texas SystemInventors: Joseph J. Beaman, Carl R. Deckard
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Patent number: 4933139Abstract: A process for the production of at least a one kilogram block of Chevrel-phase Pb.sub.x Mo.sub.y S.sub.z, wherein x=0.9 to 1.2, y=6.0 to 6.4, and z=7 to 8, includes mixing thoroughly stoichiometric quantities of starting materials in powdered form. The starting materials are selected from elemental Pb, Mo and S, sulfides of elemental Pb and Mo, and mixtures thereof. The starting mixture is introduced into a metallic container and evacuated to a pressure to 10.sup.4 Pa or less. The evacuated container is subjected to hot isostatic pressing at a constant pressure selected from a pressure ranging from 100 to 300 MPa, at a heating rate ranging from 10.degree. to 100.degree. C./hr., at a final pressing temperature ranging from 800.degree. to 1200.degree. C., and for a pressing period ranging from 10 to 100 hours, whereby the starting materials react to form the block of Chevrel-phase Pb.sub.x Mo.sub.y S.sub.z. The block is cooled at a cooling rate ranging from 50.degree. to 500.degree. C./hr.Type: GrantFiled: September 1, 1987Date of Patent: June 12, 1990Assignee: Kernforschungszentrum Karlsruhe GmbHInventors: Rene Flukiger, Wilfried Goldacker
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Patent number: 4929415Abstract: A method for sintering and forming powder is disclosed. In this method a high voltage of 3 KV or more is applied to a mold filled with powder using an electrode which maintains a high current of 50 KA cm.sup.-2 or greater for a period of time from 10 to 500 microseconds. A device for practicing this method is also disclosed.Type: GrantFiled: March 1, 1988Date of Patent: May 29, 1990Inventor: Kenji Okazaki
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Patent number: 4929417Abstract: A powder of at least one of TiB.sub.2, ZrB.sub.2 and HfB.sub.2 is mixed with at least one of Ti, Zr, Hf, TiB, ZrB and HfB, or with at least one of Ti, Zr, Hf, TiB, ZrB and HfB and a powder of boron, to prepare a mixed powder which can form a sintered product having a boron content of 65 to 67 atom %. Alternatively, a powder of at least one of Ti, Zr, Hf, TiB, ZrB and HfB is mixed with a powder of boron to prepare the mixed powder. The mixed powder may further contain up to a maximum of 30% by weight of a powder of AlN. Then, the mixed powder is sintered to make metal diboride ceramics. The lower-melting metal or compound which the mixed powder contains melts to form a liquid phase and enables the manufacture of a sintered product of high density by a customary sintering operation employing a low temperature. The sintered product having a boron content of 65 to 67 atom % consists solely of metal diboride crystals having a structure of the hexagonal system.Type: GrantFiled: April 21, 1989Date of Patent: May 29, 1990Assignee: Agency of Industrial Science and TechnologyInventors: Tadahiko Watanabe, Kazuhisa Shobu, Yukio Kai, Hideki Yamamoto, Eiichi Sudoh, Osamu Yagishita, Junshiro Hayakawa
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Patent number: 4923658Abstract: A process for the production of homogeneous flat articles of thermoplastic synthetic resins wherein a starting mixture based on thermoplastic synthetic resins is processed into agglomerate or granulated material by a thermal pretreatment above the softening temperature and subsequently, optionally after additional intermediate steps, is mechanically comminuted to a mixture of particles having a random grain size distribution. The mixture of particles is piled continuously onto a conveyor belt to form a uniform layer and is sintered, under the action of heat up to the plasticization of the thermoplastic synthetic resin, into a coherent flat articles and is then press-molded under the effect of pressure and heat.Type: GrantFiled: September 28, 1988Date of Patent: May 8, 1990Assignee: Huels Troisdorf AGInventors: Alexander Hover, Manfred Simon, Richard Weiss
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Patent number: 4913966Abstract: This invention discloses novel, porous silica structures prepared from silica platelets. The structures are preferably prepared by spray-drying.Type: GrantFiled: April 22, 1987Date of Patent: April 3, 1990Assignee: Unilever Patent Holdings B.V.Inventors: Michael J. Garvey, Ian C. Griffiths
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Patent number: 4908167Abstract: Form or pressed bodies, such as briquettes, are made of a mixture including at least two components. A first component is formed by at least one fine grained solid material which does not soften below 800.degree. C. A second component is formed by at least one binding agent that is pyrolytically decomposable. Each of the components has a mean mixing and deformation temperature such that the mean temperature of the first component is above a standard mixing and deforming temperature while the mean temperature of the second component is below the standard temperature. The standard temperature is such that a pyrolysis and degassing performed at the standard temperature does not destroy the binding ability of the second component. The second component constitutes about 15% by weight to about 50% by weight of the total mixture. Further, the second component is at least partly a liquified bituminous material having a mean CCT-value above 20%.Type: GrantFiled: March 14, 1989Date of Patent: March 13, 1990Assignee: Laborlux S. A.Inventors: Franz Beckmann, Armand Wagner
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Patent number: 4904291Abstract: A process for manufacturing open porous sintered bodies with large open pore volume and defined pore diameters and which at least predominantly consist of glass-ceramics. They are obtained by sintering a mixture of sinterable powder and an inorganic soluble salt with defined grade of grain, the melting point of which is above the densification temperature of the sinterable powder. For the formation of a molded body the mixture of sinterable powder and inorganic salt is submitted to a molding process. The molded body is sintered in a sintering process and the soluble salt being contained in the molded body is lixiviated. As a main constituent the sinterable powder contains a pulverized crystallizable glass powder.Type: GrantFiled: September 19, 1988Date of Patent: February 27, 1990Assignee: Schott GlaswerkeInventors: Friedrich Siebers, Werner Kiefer, Maria Sura
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Patent number: 4902326Abstract: A multidirectionally fiber reinforced-glass matrix composite article is disclosed. The fiber reinforcement is precisely oriented in three or more directions to provide high strength and stiffness in each of the three or more directions. A method for making a multidimensionally fiber reinforced glass matrix composite article is also disclosed. The method includes impregnating a fiber preform with a colloidal suspension of inorganic material, cooling the impregnated fiber preform to precipitate the inorganic material, drying the preform, impregnating the preform with heated glass matrix material, and cooling the glass impregnated preform to form the multidirectionally fiber reinforced glass matrix composite article.Type: GrantFiled: November 2, 1988Date of Patent: February 20, 1990Assignee: United Technologies CorporationInventor: David C. Jarmon
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Patent number: 4900240Abstract: A precompact of flowable brake-lining composition is formed in an intermediate die by pressing the material in a direction perpendicular to the generatrices of the curved surfaces between which the material is pressed, whereupon the intermediate die is swung onto the hot-pressing die and the precompact transferred between synchronously driven rams into the hot-pressing die. A horizontal ram effects the final hot pressing of the precompact, advantageously directly bonding the same to a brakeshoe.Type: GrantFiled: December 15, 1988Date of Patent: February 13, 1990Assignee: Ing. Johann Leinweber Anstalt fur MechanikInventor: Johann Leinweber
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Patent number: 4898631Abstract: An apparatus and method is disclosed for fabricating mats of ceramic material comprising preparing a slurry of ceramic particles in a binder/solvent, charging the slurry into a vessel, forcing the slurry from the vessel into spinneret nozzles, discharging the slurry from the nozzles into the path of airjets to enhance the sinuous character of the slurry exudate and to dry it, collecting the filaments on a moving belt so that the filaments overlap each other thereby forming a mat, curing the binder therein, compressing and sintering the mat to form a sintered mat, and crushing the sintered mat to produce filament shaped fragments.Type: GrantFiled: January 15, 1988Date of Patent: February 6, 1990Assignee: California Institute of TechnologyInventor: Earl R. Collins, Jr.
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Patent number: 4891174Abstract: A process for the preparation of a micro-cellular porous ceramic body is disclosed, in which an .alpha.-olefin oligomer is added as a molding assistant to an ultrafine ceramic powder in an amount of 65 to 330% by weight based on the ultrafine ceramic powder, the mixture is kneaded, the kneaded mixture is compression-molded to give a molded body, and the molded body is fired.Type: GrantFiled: October 28, 1988Date of Patent: January 2, 1990Assignee: Agency of Industrial Science and TechnologyInventors: Yachiho Seki, Saburo Kose, Teruo Kodama
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Patent number: 4889555Abstract: To produce smeltable briquets, steel-works dusts containing more that 15% metallic iron are heated in an indirectly heated rotary kiln to a briquetting temperature in excess of 500.degree. C. under an atmosphere which is inert to the metallic iron. The heated dusts are briquetted in the briquetting roll press under an inert atmosphere and under a roll pressure from 60 to 150 kN/cm roll width. The hot briquets are separated from the fines under an inert atmosphere and are air-cooled to a temperature below 130.degree. C. The fines are recycled to the rotary kiln.Type: GrantFiled: September 20, 1988Date of Patent: December 26, 1989Assignee: Metallgesellschaft AktiengesellschaftInventors: Ladislau Szekely, deceased, Fred Stieler
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Patent number: 4879263Abstract: A sliding member formed of sintered silicon nitride shows improvement in strength and abrasion resistance when substantially all the .beta.-phase type fine silicon nitride particles present as a main component in the sintered silicon nitride have major diameters not exceeding 60 .mu.m and aspect ratios of not less than 5 and the aforementioned fine silicon nitride particles have a relative density of not less than 98%.Type: GrantFiled: September 17, 1985Date of Patent: November 7, 1989Assignee: Kabushiki Kaisha ToshibaInventors: Katsutoshi Komeya, Hashimoto, Masahiro, Katsutoshi Nishida, Michiyasu Komatsu
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Patent number: 4876049Abstract: The present invention provides a method for preparing a molded article of an ultra-high molecular weight polyethylene which is characterized by compression-molding, or heating and pressurizing a porous sheet of said ultra-high molecular weight polyethylene. The porous sheet may be superposed with a substrate, and may be wrapped around a deformable member of a mold and densified by deformation of said member.Type: GrantFiled: November 19, 1986Date of Patent: October 24, 1989Assignee: Nippon Petrochemicals Co., Ltd.Inventors: Takeo Aoyama, Teruo Imai, Junichi Hattori, Mikio Uehara
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Patent number: 4873053Abstract: A method for manufacturing a metal boride ceramic material, includes mixing metal boride powder with 1-20 wt. % metal powder and 0.1-10 wt. % carbon powder, shaping the mixture and firing it. Alternatively, the metal boride powder may be mixed with 0.1-89 wt. % metal carbide powder thereby make a mixture, followed by shaping the mixture and firing it.Type: GrantFiled: February 12, 1988Date of Patent: October 10, 1989Assignees: STK Ceramics Laboratory Corp., Toshiba Ceramics Co., Ltd.Inventors: Junichi Matsushita, Hajime Saito, Hideo Nagashima
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Patent number: 4863538Abstract: A method and apparatus for selectively sintering a layer of powder to produce a part comprising a plurality of sintered layers. The apparatus includes a computer controlling a laser to direct the laser energy onto the powder to produce a sintered mass. The computer either determines or is programmed with the boundaries of the desired cross-sectional regions of the part. For each cross-section, the aim of the laser beam is scanned over a layer of powder and the beam is switched on to sinter only the powder within the boundaries of the cross-section. Powder is applied and successive layers sintered until a completed part is formed. The powder can comprise either plastic, metal, ceramic, or polymer substance. In the preferred embodiment, the aim of the laser is directed in a continuous raster scan and the laser turned on when the beam is aimed with the boundaries of the particular cross-section being formed.Type: GrantFiled: October 17, 1986Date of Patent: September 5, 1989Assignee: Board of Regents, The University of Texas SystemInventor: Carl R. Deckard
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Patent number: 4849163Abstract: A process for producing flat products from gas atomised particulate material comprises the steps of forming a relatively smooth castable slurry comprising a suspension of such particulate material in a solution of film-forming binder material, depositing a coating of the slurry onto a substrate or support surface and drying the coating to form a flexible flat product. The dried flat product may be bonded onto the substrate or support surface by the drying process or, alternatively, may be removed therefrom and roll-bonded to a suitable substrate for subsequent compaction and sintering.Type: GrantFiled: September 8, 1987Date of Patent: July 18, 1989Assignee: Mixalloy LimitedInventors: John Bellis, Nigel J. Brooks
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Patent number: 4846866Abstract: The present invention is directed to the preparation of hybrid composite bodies composed of an essentially alkali-free, alkaline earth aluminosilicate glass matrix reinforced with SiC whiskers and continuous ceramic fibers.Type: GrantFiled: December 14, 1987Date of Patent: July 11, 1989Assignee: Corning Glass WorksInventors: Kenneth Chyung, Kishor P. Gadkaree, Mark P. Taylor
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Patent number: 4843042Abstract: An aluminum nitride ceramic body with a thermal conductivity of at least 0.5 W/cm.K at 25.degree. C. is produced by shaping a particulate mixture of aluminum nitride powder and an additive selected from the group consisting of CaF.sub.2, SrF.sub.2, BaF.sub.2 and mixtures thereof into a compact and liquid phase sintering the compact.Type: GrantFiled: June 30, 1986Date of Patent: June 27, 1989Assignee: General Electric CompanyInventors: Stephen L. Dole, Ronald H. Arendt, Wayne D. Pasco
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Patent number: 4834917Abstract: Waste material such as toxic compounds, radioactive waste materials and spent nuclear fuel rods are encapsulated in a container system which is subjected to a hot pressure process to cause a protective powder material located around the waste material to form a dense matrix and function as a highly corrosion resistant and protective shroud. Embodiments include hot isostatic pressing and hot uniaxial pressing, the use of metal powder such as copper powder for the protective powder material or alternatively ceramic powder and, depending upon the embodiment chosen, the use of a single container or dual container system in which a first container is located within an outer container. Either or both of such containers may be cylindrical with a bellows-like side wall to facilitate compression thereof in an axial direction.Type: GrantFiled: June 23, 1987Date of Patent: May 30, 1989Assignees: Australian Nuclear Science & Technology Organization, The Australian National UniversityInventors: Eric J. Ramm, Albert E. Ringwood
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Patent number: 4833182Abstract: A binder for use in the preparation of a synthetic board from cellulosic and/or lignocellulosic material comprising an organic polyisocyanate and a polyester polyol, especially an aromatic polyester polyol.Type: GrantFiled: July 21, 1988Date of Patent: May 23, 1989Assignee: Jim Walter Research Corp.Inventors: Michael G. Israel, George A. Grozdits, Ernest K. Moss
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Patent number: 4832893Abstract: A method for producing PLZT generally expressed as (Pb.sub.1-x La.sub.x) (Zr.sub.1-y Ti.sub.y).sub.1-x/4 O.sub.3 (0<x.ltoreq.0.3, 0.ltoreq.y.ltoreq.1.0) comprises the steps of forming a coprecipitated body by reacting solution containing at least one of Pb, La and Ti with a zirconium-containing solution and a precipitation-forming solution, or (a) forming a solution containing at least one of Pb, La and Ti forming PLZT generally expressed as (Pb.sub.1-x La.sub.x) (Zr.sub.1-y Ti.sub.y).sub.1-x/4 O.sub.3 (0<x.ltoreq.0.3, 0.ltoreq.y.ltoreq.1.0) and a zirconium-containing solution and carrying out a hydrolysis reaction to produce a sol body, (b) drying and then presintering the coprecipitated body at a temperature of from 700.degree. to 1300.degree. C. to form a modified zirconia powder, (c) mixing the presintered body with a compound having a remaining component composition of a required PLZT composition, (d) presintering the mixture at a temperature of from 500.degree. to 1000.degree. C.Type: GrantFiled: December 16, 1987Date of Patent: May 23, 1989Assignees: Nippondenso Co., Ltd., Science and Technology Agency National InstituteInventors: Michio Hisanaga, Kazunori Suzuki, Masataka Naito, Shinichi Shirasaki
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Patent number: 4832708Abstract: Disclosed is an improvement enabling a more reliable detection of flaws in polycrystalline diamond compacts by x-ray imaging and expecially for compacts used for wire drawing dies. In an embodiment, wire die compacts are prepared having a plycrystalline diamond core disposed within a metal carbide annulus. In the core are uniformly dispersed less than five (5) percent by weight particles such as tungsten carbide which initially have an average particle size substantially less than the diamond particles used to form polycrystalline mass.Type: GrantFiled: January 29, 1987Date of Patent: May 23, 1989Assignee: General Electric CompanyInventor: Frank J. Csillag
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Patent number: 4826630Abstract: Annular pellets of burnable poison specifically boron carbide, B.sub.4 C, in a matrix of a refractory material, specifically aluminum oxide, Al.sub.2 O.sub.3, are produced. The pellets are of small wall thickness. Powders of the Al.sub.2 O.sub.3 and the B.sub.4 C are milled in a ball mill in water in which a wetting agent, a surfactant and a deflocculant are included to produce a slurry. Organic binders and plasticizers are added. Then the slurry is spray dried in a centrifugal separator. The resulting powder is poured into a mold and a turbular green body is formed by isostatic pressure. The tube may be sintered to size as a whole and then cut into lengths; i.e., pellets, or the green body may be cut into green-body pellets which are then sintered.Type: GrantFiled: February 26, 1982Date of Patent: May 2, 1989Assignee: Westinghouse Electric Corp.Inventors: Kenneth C. Radford, William C. Carlson
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Patent number: 4818570Abstract: In a process for the production of smooth surfaced parts, a paste material, which includes paste or granule pieces which are coated with added pigment and then pressed back together, is applied, in the form of an extrusion or a coating, to a substrate. The extrusion or coating is subjected to a first, incomplete hardening, after which it is no longer flows freely under its own weight. The surface layer, containing added pigment, is then removed from a surface to be used. This surface is subsequently smoothed, and the hardening of the coating to form a hard material is completed. The smoothing and the completion of the hardening can occur in the same processing step as a shaping for the formation of separable shaped parts. The substrate can be inseparable from the hardened coating. The surface layer, containing added pigment, can be removed by mechanical means, solvents or abrasion by a suspension in liquid or air, if appropriate in the presence of ultrasound.Type: GrantFiled: July 14, 1987Date of Patent: April 4, 1989Inventor: Victor A. Milles
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Patent number: 4810447Abstract: Disclosed is an improvement enabling a more reliable detection of flaws in polycrystalline diamond compacts by x-ray imaging and especially for compacts used for wire drawing dies. In an embodiment, wire die compacts are prepared having a polycrystalline diamond core disposed within a metal carbide annulus. In the core are uniformly dispersed less than five (5) percent by weight particles such as tungsten carbide which initially have an average particle size substantially less than the diamond particles used to form the polycrystalline mass.Type: GrantFiled: February 4, 1985Date of Patent: March 7, 1989Assignee: General Electric CompanyInventor: Frank J. Csillag
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Patent number: 4806279Abstract: A vibratory processing arrangement including an apparatus comprising three main stages. Namely, a high level waste vibrating impregnator, a vibrating calciner and a vibratory powder mixer.The waste impregnator comprises a downwardly inclined trough having flexible mountings and a vibrator at its upstream end, a hood structure and a series of liquid sprays connected to a high level waste supply tube.The vibratory calciner comprises a downwardly inclined tube connected to a downstream discharge tube. The discharge tube has an inlet pipe for entry of reducing gas. The reducing gas passes upwardly through the tubes to a gas discharge take-off tube near the upstream end of the downwardly inclined tube. A vibrator is tuned to provide the desired flow rate through the downwardly inclined tube.Calcined discharged powder falls downwardly into the vibratory mixer, which has a vibratory actuator and flexible mountings.Type: GrantFiled: December 1, 1986Date of Patent: February 21, 1989Assignees: Australian Atomic Energy Commission, Australian National UniversityInventor: Eric J. Ramm
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Patent number: 4797270Abstract: The process for the manufacture of special aluminas from the powder produced in the calcination of alumina hydrate, as proposed by the invention, achieves the recovery of this by-product, treating it separatedly from the rest of the alumina, in order to convert it into special alumina of high calcination degree, or alpha alumina, being adequate for uses other than aluminum production. The process is carried out by submitting the by-product to a water-washing stage that reduces its sodium content, solid and liquid separation, filtering and drying. A drying operation is finally carried out with a calcination at a high temperature wherein the alumina of high calcination degree is transformed into alpha alumina.Type: GrantFiled: September 3, 1987Date of Patent: January 10, 1989Assignee: Alumina Espanola S.A.Inventors: Jose M. Alvarado Cendan, Flor Campa Campa
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Patent number: 4776995Abstract: A carbonizable body is formed by infusing a plurality of preoxidized, preferably stabilized by known processing to have about 9 to 14 weight percent oxygen, polyacrylonitrile fibers in a polar liquid plasticizer, preferably water, capable of extracting a tarry leachate from the fibers. The infusion of the fibers in the plasticizer is continued for a sufficient time for a substantial amount of leachate to form on the surface of the fibers, and are then consolidated or diffusion-bonded to one another or other fibers, as by orienting the treated fibers in a mold and subjecting them to isostatic pressing at relatively low temperatures and pressure. Further processing of the consolidated fibers with appropriate heat treatment in an inert atmosphere will produce a carbonized bulk product with higher values of Young's modulus for the carbonized material than have been previously achieved at such carbonization temperatures.Type: GrantFiled: August 22, 1986Date of Patent: October 11, 1988Assignee: Fiber Materials, Inc.Inventors: Daniel C. Nelson, Roger T. Pepper
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Patent number: 4777014Abstract: Self-supporting bodies are produced by reactive infiltration of a parent metal with a boron source typically resulting in a composite comprising a parent metal boride and metal. The mass to be infiltrated may contain one or more inert fillers admixed with the boron source to produce a composite by reactive infiltration, which composite comprises a matrix of metal and parent metal boride embedding the filler. The relative amounts of reactants and process conditions may be altered or controlled to yield a body containing varying volume percents of ceramic, metal and/or porosity.Type: GrantFiled: March 7, 1986Date of Patent: October 11, 1988Assignee: Lanxide Technology Company, LPInventors: Marc S. Newkirk, Michael K. Aghajanian, Danny R. White
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Patent number: 4776994Abstract: A carbonizable body is formed by infusing a plurality of preoxidized, preferably stabilized by known processing to have about 17 to 30 weight percent oxygen, fibers prepared from pitch, in a non-polar liquid plasticizer, typically quinoline, capable of extracting a tarry leachate from the fibers. The infusion of the fibers in the plasticizer is continued for a sufficient time for a substantial amount of leachate to form on the surface of the fibers. The treated fibers are then consolidated or diffusion-bonded to one another or other fibers, as by orienting the treated fibers in a mold and subjecting them to isostatic pressing at relatively low temperatures and pressure. Further processing of the consolidated fibers with appropriate heat treatment in an inert atmosphere will produce a carbonized bulk product with higher values of Young's modulus for the carbonized material than have been previously achieved at such carbonization temperatures.Type: GrantFiled: August 22, 1986Date of Patent: October 11, 1988Assignee: Fiber Materials, Inc.Inventors: Daniel C. Nelson, Roger T. Pepper
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Patent number: 4774051Abstract: A sintered nuclear fuel compact of UO.sub.2 or the mixed oxides (U, Pu)O.sub.2 and (U, Th)O.sub.2, with which reactivity losses in a nuclear reactor having relatively long fuel element cycles are avoided, has in its sintered matrix neutron poison in the chemical compound form UB.sub.x with x=2; 4 and/or 12 and/or B.sub.4 C. A sintered nuclear fuel compact of this kind is produced by sintering from a compact comprising a mixture of at least one of the mixture components UO.sub.2, PuO.sub.2, (U, Pu)O.sub.2 and (U, Th)O.sub.2 powder with UB.sub.x powder, where x=2; 4 and/or 12 and/or B.sub.4 C powder.Type: GrantFiled: March 12, 1987Date of Patent: September 27, 1988Assignee: Kraftwerk Union AktiengesellschaftInventors: Martin Peehs, Wolfgang Dorr
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Patent number: 4769350Abstract: A silicon nitride sintered material for cutting tools comprising from about 3 to 10 wt % of partially stablized zirconium oxide, from about 1 to 5 wt % of aluminum oxide, and from about 1 to 10 wt % of yttrium oxide, the balance being silicon nitride, and the process for making the same.Type: GrantFiled: September 30, 1987Date of Patent: September 6, 1988Assignee: Sumitomo Electric Industries, Ltd.Inventors: Takao Nishioka, Akira Yamakawa, Masaya Miyake
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Patent number: 4769242Abstract: A process for preparing an insect-repellent and insecticidal article for breeding plants including forming a clathrate compound consisting of an organophosphorus or a pyrethroid insecticide included in cyclodextrin; mixing the clathrate compound with a synthetic resin compound and molding the mixture into an article for breeding plants.Type: GrantFiled: November 29, 1985Date of Patent: September 6, 1988Assignee: Japan Liquid Crystal Co., Ltd.Inventor: Ichiro Shibanai
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Patent number: 4765950Abstract: Provided is a method of manufacturing sintered parts from particulate material, e.g metal or ceramic parts. The method comprises mixing together predetermined amounts of powdered particulate material and a binder, which mixture is then molded under heat and pressure. The binder comprises at least a lower melting point component and a higher melting point component, with the lower melting point component remaining in a liquid state, becoming semi-solid or relatively soft upon cooling to ambient temperatures. Prior to sintering, the lower melting point component of the binder is selectively dissolved in a liquid solvent, and the higher melting point component is removed upon heating at temperatures below the sintering temperature. The result is a process which eliminates or prevents the formation of oxides, substantially reduces the time required for debinding and sintering, and essentially eliminates cracking in the finished part.Type: GrantFiled: October 7, 1987Date of Patent: August 23, 1988Assignee: Risi Industries, Inc.Inventor: Kenneth P. Johnson
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Patent number: 4764318Abstract: Coke for reactor graphite is produced continuously by coking a hard pitch with a softening point (K.-S.) above 130.degree. C. and a coking residue of at least 45% by weight in a rotary pipe furnace equipped with a moving device and subsequent calcination without intermediate cooling. The temperature of the inner wall of the indirectly heated furnace ranges from about 500.degree. to about 800.degree. C. The gases and vapors formed during the coking process are guided in countercurrent flow to the pitch.Type: GrantFiled: March 6, 1987Date of Patent: August 16, 1988Assignee: Ruetgerswerke AktiengesellschaftInventors: Manfred Morgenstern, Claus Bertrand
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Patent number: 4764424Abstract: Solid particles are coated with a uniform and continuous polyamide layer by immersion in a reaction medium capable of forming polyamides by anionic polymerization in solution.Type: GrantFiled: March 31, 1986Date of Patent: August 16, 1988Assignee: AtochemInventors: Roland Ganga, Jacques Grossoleil, Jean-Paul Merval
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Patent number: 4761262Abstract: A method for sintering a metal powder, a ceramic powder, or a mixture thereof accomplishes compact sintering of even a high melting substance by heating the powder at an elevated temperature for a short time under not less than 10,000 atmospheres of pressure. To attain the quick high-temperature heating under the ultrahigh pressure, a Thermit reaction is generated in an ultrahigh pressure generating apparatus which is provided with a gasket made of pyrophyllite and cylinders and anvils protected with heat insulators.For the purpose of preventing the Thermit reaction from inducing a reaction between the Thermit composition and the powder under treatment and the heater and ensuring electrical insulation of these components, barriers made of hexagonal boron nitride and/or tantalum are suitably disposed within the apparatus.Type: GrantFiled: October 8, 1986Date of Patent: August 2, 1988Assignee: Kabushiki Kaisha Komatsu SeisakushoInventors: Masaru Ogata, Shuichi Takeda
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Patent number: 4759887Abstract: A process for the manufacture of shaped bodies from silicon granulates for producing silicon melts includes first incipiently melting silicon grains on their surfaces, so that they bond with their neighbors in the process and, after solidifying, form a porous compound shaped body which only then may be melted completely. Such compound shaped bodies can be manufactured continuously or semi-continuously and converted without difficulty by a subsequent step into the molten state. An apparatus for producing shaped bodies is also provided which preferably employs an electron beam, to supply energy to incipiently melt the granulate.Type: GrantFiled: May 12, 1986Date of Patent: July 26, 1988Assignee: Heliotronic Forschungs- und Entwicklungs-gesellschaft fur Solarzellen-Grundstoffe mbHInventors: Joachim Geissler, Deiter Helmreich, Roland Luptovits, Maximilian Semmler, Burkhard Walter
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Patent number: 4758404Abstract: In a method of producing a composite material for a sliding member having a sliding portion and a backing material which supports the sliding portion, the method comprises the steps of: disposing a powder or a sheet material for the sliding portion on the backing material; irradiating the powder or sheet material with laser beam or electron beam; melting or partially melting the beam-irradiated powder or sheet material; and quenching and solidifying the melted or partially melted portion, whereby the particles of the powder are integrated with one another and the powder in contact with the backing material are bonded thereto, or whereby the sheet material in contact wiht the backing material are bonded thereto.Type: GrantFiled: October 21, 1986Date of Patent: July 19, 1988Assignee: Daido Metal Company, Ltd.Inventor: Takashi Muto
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Patent number: 4756955Abstract: The invention relates to a high density composite sheet based on discontinuous mineral fibers. The inventive sheet has a content of mineral fibers greater than 70 wt. % of the total weight of fibers and binder, and has a density between 400 and 1600 kg/m.sup.3. The sheet can be employed in particular as an architectural structural wall facing, as a component of a composite insulating panel, etc., and is formed by compressing at high pressure at least one non-woven layer of discontinuous mineral fibers provided with a polymerizable resin which is cured during compression.Type: GrantFiled: March 31, 1987Date of Patent: July 12, 1988Assignee: Isover Saint-Gobain RechercheInventor: Jean-Claude Rias
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Patent number: 4756752Abstract: A method for forming a high density body from a powder material of metallic and non-metallic compositions and combinations thereof comprising confining a quantity of the powder material in a flexible mold structure, subjecting the powder material in the mold structure to a predetermined pressure along one axis while confining the material against movement in directions normal to the axis so as to form a compact body of the powder material and subsequently heating the compact body to a predetermined temperature so as to further compact the body. A quantity of glass is heated so that it will flow and transmit pressure following which the heated body is immersed in the heated glass and the flowable glass is subjected to a pressure high enough to further compact the body. The resulting densified body is uniformly compressed in the directions of three mutually perpendicular axes extending through the body.Type: GrantFiled: November 4, 1987Date of Patent: July 12, 1988Assignee: Star Cutter CompanyInventor: Lewis J. Barnard