Sintering Which Includes A Chemical Reaction Patents (Class 419/45)
  • Patent number: 5342572
    Abstract: In accordance with this invention, there is provided a process for producing a shaped article in which a reaction mixture containing at least two elemental materials is first charged into a die to form a shaped green body. A uniaxial pressure of from about 500 to about 5,000 pounds per square inch of cross-sectional area of the green body is then uniaxially applied to the green body, and the green body is then ignited; during ignition, the uniaxial pressure of from about 500 to about 5,000 pounds per square inch is maintained at a substantially constant level and continually applied to the reaction mixture.
    Type: Grant
    Filed: September 27, 1993
    Date of Patent: August 30, 1994
    Assignee: Alfred University
    Inventors: Gregory C. Stangle, William C. Williams
  • Patent number: 5340533
    Abstract: A process for producing a dense composite material by combustion synthesis. In the first step of the process, a reaction mixture comprised of an elemental material is provided. The elemental material is charged to a die, a uniaxial pressure of from about 500 to about 5,000 pounds per square inch is applied to the elemental material within the die, and the elemental material within the die is ignited. Prior to, during, and subsequent to the time said elemental material is been ignited, the uniaxial pressure of from about 500 to about 5,000 pounds per square inch is applied to the elemental material within said die.
    Type: Grant
    Filed: April 27, 1993
    Date of Patent: August 23, 1994
    Assignee: Alfred University
    Inventors: Gregory C. Stangle, Scott E. Niedzialek, William C. Williams
  • Patent number: 5338372
    Abstract: Anisotropic rare-earth permanent magnets characterized in that an aggregate of a plurality of blocks, to each of which anisotropy is imparted, is formed using powders of magnetic material containing rare-earth elements, and the adjoining blocks are powder-metallurgically bonded together under pressure into one piece; a method of making anisotropic rare-earth permanent magnets by molding anisotropic blocks by magnetic-field molding, arranging, aggregating and sealing a plurality of blocks in a bag, and cold hydrostatic pressing the aggregate of blocks in the absence of magnetic field; and a suitable metal mold for magnetic-field molding anisotropic permanent magnets of a relatively large size.
    Type: Grant
    Filed: December 3, 1992
    Date of Patent: August 16, 1994
    Assignee: Hitachi Metals, Ltd.
    Inventor: Kazunori Tabaru
  • Patent number: 5314656
    Abstract: Transition metal carbonitrides (in particular, titanium carbonitride, TiC.sub.0.5 N.sub.0.5) are synthesized by a self-propagating reaction between the metal (e.g., titanium) and carbon in a nitrogen atmosphere. Complete conversion to the carbonitride phase is achieved with the addition of TiN as diluent and with a nitrogen pressure .gtoreq.0.6 MPa. Thermodynamic phase-stability calculations and experimental characterizations of quenched samples provided revealed that the mechanism of formation of the carbonitride is a two-step process. The first step involves the formation of the nonstoichiometric carbide, TiC.sub.0.5, and is followed by the formation of the product by the incorporation of nitrogen in the defect-structure carbide.
    Type: Grant
    Filed: November 20, 1992
    Date of Patent: May 24, 1994
    Assignee: The Regents of the University of California
    Inventors: Zuhair A. R. Munir, Maryam Eslamloo-Grami
  • Patent number: 5312582
    Abstract: A process for producing porous structures for use in molten carbonate fuel cells in which a powder comprising at least one of a non-alloyed metal powder and a metal oxide powder, and a ceramic oxide powder is mixed, formed into a desired shape and sintered in an oxidizing atmosphere at a temperature between 900.degree. C. and about 1400.degree. C. via reactive oxidation to form a sintered oxide structure, which is then cooled to 700.degree. C. to 1100.degree. C. and treated in a reducing atmosphere to form a metallic structure with the non-reducible oxide dispersed within the metal.
    Type: Grant
    Filed: February 4, 1993
    Date of Patent: May 17, 1994
    Assignee: Institute of Gas Technology
    Inventor: Rafael A. Donado
  • Patent number: 5304342
    Abstract: A sintered product useful for abrasion- and impact-resistant tools and the like is provided comprising an iron-group metal binder and refractory metal carbide particles, e.g. tungsten carbide, formed in situ during sintering by the exothermic reaction of a carbide-forming refractory metal powder with a carbon source mixed therewith. The sintering is carried out at an elevated temperature and at a pressure at which diamond is stable in the presence of a liquid phase comprised substantially of an iron-group binder metal, refractory metal, and dissolved carbon. The product may optionally contain diamond, up to about 95% in volume, enabling its properties to be tailored for a wide range of applications.
    Type: Grant
    Filed: June 11, 1992
    Date of Patent: April 19, 1994
    Inventors: H. Tracy Hall, Jr., David R. Hall
  • Patent number: 5304343
    Abstract: An aluminum-alloy main-starting powder for producing a sintered aluminum-alloy consists of from 0.1 to 3.0% of Cu, the balance being Al and unavoidable impurities. Mother alloy powder consists of from 4 to 20% of Mg, from 12 to 30% of Si, and Al and unavoidable impurities in balance.
    Type: Grant
    Filed: October 19, 1992
    Date of Patent: April 19, 1994
    Assignee: Showa Denko K.K.
    Inventors: Shin Miura, Youichi Hirose, Yoshio Machida, Mitsuaki Sato
  • Patent number: 5302340
    Abstract: A method of forming a ceramic layer, which is compact and rich in adhesion to a metallic body, on the metallic body without adding binders even though said ceramics is hard to be sintered ceramics such as various kinds of non oxide ceramics. Said method comprises a step of placing ceramic powders and/or a mixture of ceramic powders and metallic powders or a mixture of metallic powders and non metallic powders on the metallic body and a step of forming the ceramic layer on the metallic body in a moment by a reaction heat of the Thermit.RTM. reaction under the pressurized condition. In addition, a metallic insert member can be disposed between said metallic body and various kinds of powder placed on said metallic body. Furthermore, the resulting ceramic/metal composite member is subjected to a hot hydrostatic pressing or a hot pressing under high temperatures and high pressures.
    Type: Grant
    Filed: May 5, 1992
    Date of Patent: April 12, 1994
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventor: Shuichi Takeda
  • Patent number: 5298468
    Abstract: Densified boron carbide-aluminum, ceramic-metal composites that are substantially free of AlB.sub.12, AlB.sub.12 C.sub.2 and Al.sub.4 C.sub.3 result from a two stage process. Admixtures of boron carbide are densified under pressure in stage one, In stage two, the densified admixture is heat treated. In both stages, the temperature is less than 800.degree. C. If the temperatures do not exceed 600.degree. C., the resultant densified cermet has only three phases: a) boron carbide; b) Al.sub.4 BC; and c) aluminum.
    Type: Grant
    Filed: October 13, 1992
    Date of Patent: March 29, 1994
    Assignee: The Dow Chemical Company
    Inventor: Aleksander J. Pyzik
  • Patent number: 5288670
    Abstract: This invention relates generally to a novel method of preparing self-supporting bodies, and to novel products made thereby. In its more specific aspects, this invention relates to a method of producing self-supporting bodies comprising one or more boron-containing compounds, e.g., a boride or a boride and a carbide, by reactive infiltration of a molten parent metal actinide into (1) a bed or mass containing boron carbide and, optionally, (2) at least one of a boron donor material (i.e., a boron-containing material) and a carbon donor material (i.e., a carbon-containing material), (3) a bed or mass comprising a mixture of a boron donor material and a carbon donor material and, optionally, (4) one or more inert fillers in any of the above masses, to form the body.
    Type: Grant
    Filed: November 23, 1992
    Date of Patent: February 22, 1994
    Assignee: Lanxide Technology Company, LP
    Inventor: Paul V. Kelsey
  • Patent number: 5286441
    Abstract: A silver-metal oxide composite material comprising a silver matrix, (a) from 1 to 20% by weight, in terms of elemental metal, of an oxide of at least one element selected from the group consisting of Sn, Cd, Zn and In and, optionally, (b) an oxide of Mg, Zr, etc. and/or (c) an oxide of Cd, Sb, etc.; the oxides being dispersed in the form of fine particles with a particle size of not more than about 0.1 .mu.m uniformly and being bound to the silver matrix with no space left, and a process for producing the same. The composite material is excellent in physical and chemical strengths at high temperatures. The process can produce the composite product even with thick walls, within a markedly short time in high productivity. The composite material is useful as electrical contact materials and electrode materials for electric welding.
    Type: Grant
    Filed: June 3, 1992
    Date of Patent: February 15, 1994
    Assignees: Akira Shibata, Sumico Management Planning Company, Ltd.
    Inventor: Akira Shibata
  • Patent number: 5284614
    Abstract: Doped tungsten powder, or sintered tungsten bodies formed therefrom, having a fine dispersion of oxide particles of at least one metal from the group zirconium, hafnium, lanthanum, yttrium, and rare earth's are formed by the method of this invention. A mixture of a salt solution comprised of a soluble salt of the metal, and a tungsten blue oxide powder is formed. A hydroxide precipitating solution is admixed with the mixture to form a hydroxide precipitate of the metal on the tungsten blue oxide powder. The tungsten blue oxide powder and hydroxide precipitate are heated in a reducing atmosphere to form the tungsten powder having the dispersion of oxide particles. The doped tungsten powder can be consolidated and sintered to form tungsten bodies having a fine dispersion of the metal oxide.
    Type: Grant
    Filed: June 1, 1992
    Date of Patent: February 8, 1994
    Assignee: General Electric Company
    Inventors: Li-Chyong Chen, Stephen L. Dole, Ronald H. Arendt
  • Patent number: 5273709
    Abstract: Neutron absorbing refractory B.sub.4 C-Gd and Gd.sub.2 O.sub.3 -Gd cermets, B.sub.4 C-Gd and Gd.sub.2 O.sub.3 -Gd metal-matrix composites, and B.sub.4 C-Gd.sub.2 O.sub.3 ceramic-ceramic composites can be manufactured by applying fundamental thermodynamic and kinetic guidelines as processing principals.Three steps are involved in the fabrication of these new compositions of matter. First, the starting materials are consolidated into a compacted porous green body. Next, the green body is densified using the appropriate method depending on the class of material sought: cermet, metal-matrix composite, or ceramic-ceramic composite. Finally, either during the densification process or by subsequent heat treatment, new phase evolution is obtained via interfacial chemical reactions occurring in the microstructures.The existence of a new phase has been identified in B.sub.4 C-Gd and B.sub.4 C-Gd.sub.2 O.sub.3 composites.
    Type: Grant
    Filed: August 24, 1992
    Date of Patent: December 28, 1993
    Assignee: Thermal Technology Inc.
    Inventors: Danny C. Halverson, Garth W. Billings, George M. Johnston
  • Patent number: 5269830
    Abstract: A process for synthesizing intermetallic compounds from elemental powders. The elemental powders are initially combined in a ratio which approximates the stoichiometric composition of the intermetallic compound. The mixed powders are then formed into a compact which is heat treated at a controlled rate of heating such that an exothermic reaction between the elements is initiated. The heat treatment may be performed under controlled conditions ranging from a vacuum (pressureless sintering) to compression (hot pressing) to produce a desired densification of the intermetallic compound. In a preferred form of the invention, elemental powders of Fe and Al are combined to form aluminide compounds of Fe.sub.3 Al and FeAl.
    Type: Grant
    Filed: October 26, 1990
    Date of Patent: December 14, 1993
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Barry H. Rabin, Richard N. Wright
  • Patent number: 5256368
    Abstract: A pressure-reaction synthesis process for producing increased stiffness and improved strength-to-weight ratio titanium metal matrix composite materials comprising exothermically reacting a titanium powder or titanium powder alloys with non-metal powders or gas selected from the group consisting of C, B, N, BN, B.sub.4 C, SiC and Si.sub.3 N.sub.4 at temperatures from about 900.degree. to about 1300.degree. C., for about 5 to about 30 minutes in a forming die under pressures of from about 1000 to 5000 psi.
    Type: Grant
    Filed: July 31, 1992
    Date of Patent: October 26, 1993
    Assignee: The United States of America as represented by the Secretary of the Interior
    Inventors: Laurance L. Oden, Thomas L. Ochs, Paul C. Turner
  • Patent number: 5248475
    Abstract: Methods are provided for fabricating a sintered and solid element from an otherwise unsinterable material, utilizing the property of that material that it will form an eutectic composition or alloy with a suitable alloying agent at a temperature which is below the plastic deformation temperature of the material. Discrete particles of the material to be sintered--such as grains or wire pieces--are coated with a thin coating of the alloying agent and are packed into the position where they are to be sintered. Then, the coated grains or wire pieces are heated so that at least the coating and the regions of the grains just below the coating are slowly raised in temperature. Diffusion regions of the alloying agent into the grains of the sinterable material will then occur. Further heating continues so that at least the diffusion regions increase in temperature to just slightly above the eutectic melting point.
    Type: Grant
    Filed: October 24, 1991
    Date of Patent: September 28, 1993
    Assignee: Derafe, Ltd.
    Inventor: Robert S. Feldstein
  • Patent number: 5242654
    Abstract: A process for producing strip products which comprises forming an aqueous slurry of a suspension of metallic particles in a film forming cellulose derivative, depositing a quantity of the slurry onto a support surface, drying the slurry to form a self supporting flat product, removing the dried product from the support surface and roll compacting the same to produce a green strip. The green strip is supported on a moving surface as it travels to and enters a heater in which it is heated in an oxidising atmosphere to a temperature at which substantially all traces of the cellulose derivative are removed. The heated strip is fed while still on the moving support surface to and through a sinter furnace to form a coherent strip of the required composition.
    Type: Grant
    Filed: January 27, 1992
    Date of Patent: September 7, 1993
    Assignee: Mixalloy Limited
    Inventors: Robert F. Ward, Nigel J. Brooks
  • Patent number: 5240495
    Abstract: In situ formation of metal-ceramic oxide microstructures is carried out on a starting oxide phase containing at least a most noble metallic component (e.g., iron) and a least noble metallic component (e.g. manganese) and subjecting the starting oxide phase to a temperature and oxygen partial pressure and for a time period to cause reduction of only part of the most noble metallic component to elemental metal.
    Type: Grant
    Filed: April 2, 1992
    Date of Patent: August 31, 1993
    Assignee: Cornell Research Foundation, Inc.
    Inventors: Rudiger Dieckmann, Stephen L. Sass
  • Patent number: 5198188
    Abstract: Disclosed is a method of producing dense refractory products, comprising:(a) obtaining a quantity of exoergic material in powder form capable of sustaining a combustion synthesis reaction;(b) removing absorbed water vapor therefrom;(c) cold-pressing said material into a formed body;(d) plasma spraying said formed body with a molten exoergic material to form a coat thereon; and(e) igniting said exoergic coated formed body under an inert gas atmosphere and pressure to produce self-sustained combustion synthesis.Also disclosed are products produced by the method.
    Type: Grant
    Filed: January 16, 1991
    Date of Patent: March 30, 1993
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: J. Birch Holt, Michael Kelly
  • Patent number: 5194219
    Abstract: Very good masking of pack diffusion aluminizing or chromizing on any metal to keep portions from being diffusion coated, is effected by localized coating the lowest layer of which is depletion-reducing masking powder the metal portion of which can have same composition as substrates, mixed with inert refractory diluent and non-contaminating film-former such as acrylic resin. The upper coating layer can be of non-contaminating particles like nickel or Cr.sub.2 O.sub.3 that upon aluminizing or chromizing become coherently held together to form a secure sheath. Such sheath can also be used for holding localized diffusion-coating layer in place. Film-former can be dissolved in volatile solvent, preferably methyl chloroform, in which masking powder or sheath-forming powder is suspended. Chromizing can be performed before aluminizing for greater effects. Aluminizing of metals like iron and nickel followed by leaching out much of the diffused-in aluminum, gives these substrates a pyrophoric and catalytic surface.
    Type: Grant
    Filed: July 7, 1992
    Date of Patent: March 16, 1993
    Assignee: Alloy Surfaces Company, Inc.
    Inventor: Alfonso L. Baldi
  • Patent number: 5183631
    Abstract: A composite material is provided which includes a discrete phase including grains made of a first substance; and a continuous phase including a thin coating film made of a second substance and formed on the surface of each of the grains. The thin coating film has a mean thickness smaller than the mean particle size of the grains. The grains are separated substantially from each other by the thin coating film. The porosity of the composite material is 5% or less.
    Type: Grant
    Filed: June 8, 1990
    Date of Patent: February 2, 1993
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Koichi Kugimiya, Yasuhiro Sugaya, Osamu Inoue, Mitsuo Satomi, Ken Hirota
  • Patent number: 5166105
    Abstract: This invention relates generally to a novel method of preparing self-supporting bodies, and to novel products made thereby. In its more specific aspects, this invention relates to a method of producing self-supporting bodies comprising one or more boron-containing compounds, e.g., a boride or a boride and a carbide, by reactive infiltration of a molten parent metal actinide into (1) a bed or mass containing boron carbide and, optionally, (2) at least one of a boron donor material (i.e., a boron-containing material) and a carbon donor material (i.e., a carbon-containing material), (3) a bed or mass comprising a mixture of a boron donor material and a carbon donor material and, optionally, (4) one or more inert fillers in any of the above masses, to form the body.
    Type: Grant
    Filed: December 10, 1990
    Date of Patent: November 24, 1992
    Assignee: Lanxide Technology Company, LP
    Inventor: Paul V. Kelsey
  • Patent number: 5162099
    Abstract: The process serves for producing a carbon-containing sintered compact from steel powder. In this process, the steel powder is heated to sintering temperature in an atmosphere containing, at least for a time, carbon monoxide, is kept at sintering temperature over a predetermined period of time and the sintered compact formed thereby is subsequently cooled.In this process, the carbon content of the sintered compact to be produced is to be set to a predetermined value in a way which is simple and suitable for mass production.This is achieved by the partial pressure of the carbon monoxide in the atmosphere being changed selectively during the execution of the production process, and by this change being controlled in such a way that the carbon content of the sintered compact is set to the predetermined value after execution of the production process.
    Type: Grant
    Filed: March 3, 1992
    Date of Patent: November 10, 1992
    Assignee: Asea Brown Boveri Ltd.
    Inventors: Gundolf Meyer, Christoph Tonnes
  • Patent number: 5156805
    Abstract: A ferritic alloy with a wear resistive oxide scale is obtained through the steps of pressing a ferritic alloy powder containing aluminum into a powder compact of a desired configuration, sintering the powder compact in a non-oxidizing atmosphere to provide a resulting sintered product, and heat-treating the sintered product in an oxidizing gas atmosphere in order to precipitate in the surface thereof alumina in the form of an alumina scale as the wear resistive oxide scale which is responsible for improved surface hardness or wear resistance. Due to the inherent porous nature of the sintered product, the oxidizing gas can readily penetrate deep into the surface of sintered product to facilitate the oxidization of the product surface into the alumina scale, in addition to that the oxidization depth can be controlled such as by the density of the product, which makes it possible to readily control the thickness of the alumina scale.
    Type: Grant
    Filed: July 25, 1991
    Date of Patent: October 20, 1992
    Assignee: Matsushita Electric Works, Ltd.
    Inventors: Junji Imai, Shuji Yamada, Tadashi Hamada, Hajime Kojima, Masao Tanahashi
  • Patent number: 5139720
    Abstract: In a method of manufacturing a sintered ceramic material using the heat generated in a thermit reaction as a heating source, a pre-heating is applied preceding to the sintering step or a mixture comprising: (A) at least one ceramic powder, (B) at least one non-metallic powder selected from the group consisting of carbon, boron and silicon, and (C) a metal powder and/or a non-metallic powder other than the above-mentioned (B) is used. Homogeneous and dense sintered ceramic material or sintered composite ceramic material can be obtained by this method, and the fine texture thereof, and the phase constitution, the phase distribution and the like of the composite ceramic phase can be controlled sufficiently.
    Type: Grant
    Filed: February 12, 1991
    Date of Patent: August 18, 1992
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventors: Shuichi Takeda, Hideki Shishiba
  • Patent number: 5120681
    Abstract: A composition containing MgAl.sub.2 O.sub.4, SiC, and B.sub.4 C is produced by the method comprising:(a) combining sources of magnesium silicate, B.sub.2 O.sub.3, Al and C to form a mixture, and(b) heating the mixture whereby the sources react to form MgAl.sub.2 O.sub.4, SiC, and B.sub.4 C.A sintered material containing MgAl.sub.2 O.sub.4, SiC, and B.sub.4 C, may be produced by the method comprising:(a) combining sources of magnesium silicate, B.sub.2 O.sub.3, Al and C to form a mixture,(b) compacting the mixture into a shape,(c) heating the shape, whereby the sources react to form MgAl.sub.2 O.sub.4, SiC, and B.sub.4 C, and(d) sintering the reacted shape.Possible sources of magnesium silicate are talc, vermiculite and mica.
    Type: Grant
    Filed: May 23, 1991
    Date of Patent: June 9, 1992
    Assignee: W. R. Grace & Co.-Conn.
    Inventor: Craig P. Cameron
  • Patent number: 5116568
    Abstract: An improved temperature stable synthetic polycrystalline diamond (PCD) product includes at least one temperature stable PCD integrally and chemically bonded to a matrix carrier support through a carbide forming layer which is of a thickness of at least about 1 micron, the layer on at least one surface of the PCD is in turn is bonded to the matrix carrier. A wide variety of shapes, sizes and configurations of such products is achieved through relatively low temperature and relatively low pressure processing. Various products of various geometries are described as well as the details of the processing to achieve chemical bonding of the PCD elements in a variety of support matrix carrier materials to form a unitary structure having a temperature stability up to about 1,200 degrees C.
    Type: Grant
    Filed: May 31, 1991
    Date of Patent: May 26, 1992
    Assignee: Norton Company
    Inventors: Chien-Min Sung, Sy-Hwa Chen
  • Patent number: 5110688
    Abstract: The present invention relates to a method of fabricating various types of bearing materials and the bearing materials produced thereby. The processes of the invention may be used to produce porous self-lubricating bearings, laminated composite bearings (babbitt bearings) and bearings for high temperature application. The processes of the invention involve the use of micro-pyretic synthesis to achieve bearing materials with improved bearing properties, including higher bearing capacity and toughness.
    Type: Grant
    Filed: December 3, 1990
    Date of Patent: May 5, 1992
    Assignee: University of Cincinnati
    Inventors: Jainagesh A. Sehkar, A. K. Bhattacharya, Hung P. Li
  • Patent number: 5087413
    Abstract: Vias each having no pore are formed in a multilayer ceramic substrate by filling through holes of green sheets with conducting material obtained by: kneading mixed powder particles, the powder particles produced by adding copper oxide powder particles in the amount of 50% (in weight) or less to copper powder particles, with a solution including methyl ethyl ketone and 0.5% (in weight) of isosulfonyltridecylbenzene titanate; drying and cracking the kneaded mixed powder particles, producing cracked mixed powder particles; classifying the cracked mixed powder particles with a 100 mesh filter, producing classified mixed powder particles; spheroidizing the classified mixed powder particles with a collision method performed in gases flowing at high speed; and firing the green sheets at a temperature of about 800.degree. C.
    Type: Grant
    Filed: January 9, 1991
    Date of Patent: February 11, 1992
    Assignee: Fujitsu Limited
    Inventor: Kenichiro Abe
  • Patent number: 5053192
    Abstract: The invention relates to the powder metallurgy. The invention involves deforming combustion products by extrusion at an extrusion temperature chosen in the range from 0.3T.sub.1 to T.sub.2, wherein T.sub.1 is the melting point of a hard phase of the combustion products and T.sub.2 is the melting point of a binder material in a container (5) made up of vertically extending segments (12) defining spaces (13) with one another and having a die (14) and a heat insulated sizing member (17) the temperature conditions of extrusion being controlled by means of a unit (21) having a temperature pick-up (22) and a member (23) receiving information from the pick-up (22) and sending a command for moving the punch (10).
    Type: Grant
    Filed: August 23, 1990
    Date of Patent: October 1, 1991
    Inventors: Alexandr G. Merzhanov, Alexandr M. Stolin, Vadim V. Podlesov, Leonid M. Buchatsky, Tatyana N. Shishkina
  • Patent number: 5045278
    Abstract: An aluminum based metal matrix composite is produced from a charge containing a rapidly solidified aluminum alloy, a carbidiferous agent and particles of a reinforcing material present in an amount ranging from about 0.1 to 50% by volume of the charge. The charge is ball milled energetically to uniformly mix the carbidiferous agent within the aluminum matrix, and to enfold metal matrix material around each of the particles while maintaining the charge in a pulverulent state. Upon completion of the ball milling step, the charge is hot consolidated at suitable temperatures to decompose the carbidiferous agent and result in the formation of carbide and oxide particles, and to provide a powder compact having a formable, substantially void-free mass. The compact is especially suited for use in aerospace, automotive, electronic, wear resistance critical components, and the like, which often encounter service temperatures approaching 500.degree. C.
    Type: Grant
    Filed: November 9, 1989
    Date of Patent: September 3, 1991
    Assignee: Allied-Signal Inc.
    Inventors: Sontosh K. Das, Michael S. Zedalis, Paul S. Gilman
  • Patent number: 5043320
    Abstract: A powder-in-tube method is disclosed for making a composite superconducting oxide wire which comprises loading a copper tube with a mixture composed of rare earth metal oxide, BaO.sub.2 and copper oxide or the finished superconductor powder and subjecting the loaded tube to drawing and a heat treatment at a temperature of up to 950.degree. C., wherein prior to loading the copper tube, the tube is oxidized at least on its inside to form a copper oxide layer having a thickness of 1 to 100 .mu.m and then a silver intermediate layer is inserted to the oxidized copper tube.
    Type: Grant
    Filed: February 20, 1990
    Date of Patent: August 27, 1991
    Assignee: Asea Brown Boveri AG
    Inventors: Gundolf Meyer, Erwin Schonfeld, Clemens Verpoort
  • Patent number: 5041159
    Abstract: An improved method of forming a nickel plaque wherein an assemblage of particles of a nickel alloy are oxidized and sintered in a preselected atmosphere such that the alloying material is exclusively substantially internally oxidized and the resultant product sintered to provide a sintered porous plaque containing nickel metal and oxidized alloying material.
    Type: Grant
    Filed: February 13, 1989
    Date of Patent: August 20, 1991
    Assignee: Energy Research Corporation
    Inventors: Joel D. Doyon, Lawrence M. Paetsch, Mark Benedict, D. Lynn Johnson
  • Patent number: 5034053
    Abstract: A hard sintered compact for tools is a sintered compact obtained by super-high pressure sintering of 45-75% by vol. of cubic boron nitride powder and the remaining proportion of binder powder. The binder includes 5-25% by wt. of Al and the remaining proportion of at least one species of compounds represented by (Hf.sub.1-z M.sub.z) C, where M denotes elements of IVa, Va and VIa groups in a periodic table except for Hf, and 0.ltoreq.z.ltoreq.0.3 is satisfied. Because of this composition, improvements are made in strength, wear resistance and heat resisting property of the binder, and a hard sintered compact for tools having excellent strength and excellent wear resistance can be obtained.
    Type: Grant
    Filed: November 21, 1990
    Date of Patent: July 23, 1991
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Tetsuo Nakai, Mitsuhiro Goto
  • Patent number: 5017334
    Abstract: Self-supporting bodies are produced by reactive infiltration of a parent metal into a boron carbide material which may contain one or both of a boron donor material and a carbon donor material. The reactive infiltration typically results in a composite comprising a boron-containing compound, a carbon-containing compound and residual metal, if desired. The mass to be infiltrated may contain one or more inert fillers admixed with the boron carbide material, boron-containing compound and/or carbon-containing compound. The relative amounts of reactants and process conditions may be altered or controlled to yield a body containing varying volume percents of ceramic, metal, ratios of one ceramic to another and porosity.
    Type: Grant
    Filed: December 5, 1989
    Date of Patent: May 21, 1991
    Assignee: Lanxide Technology Company, LP
    Inventors: Terry D. Claar, Steven M. Mason, Kevin P. Pochopien, Danny R. White, William B. Johnson
  • Patent number: 5017217
    Abstract: A method for manufacturing ceramic/metal or ceramic/ceramic composite articles is disclosed. The articles can be useful for the production of aluminum in fused salt electrolysis cells, as armor plates for the protection against projectiles, cutting tools, or in abrasion resistance applications. The temperature slope of the process if optimized such that one of the reactants in the manufacturing proceeds through peritectic decomposition at a heating rate of low temperature increase for desirably uniform temperature distribution over the reaction mixture. Then the temperature increase is greatly elevated to obtain a reaction sintering condition for avoiding grain growth of undesired reaction products. Elevated temperature reaction sintering conditions can be maintained to decompose undesired components before they are entrapped by the reaction product.
    Type: Grant
    Filed: August 21, 1990
    Date of Patent: May 21, 1991
    Assignee: Eltech Systems Corporation
    Inventors: Thomas M. Clere, Gholamreza J. Abbaschian, Douglas J. Wheeler, Albert L. Barnes
  • Patent number: 5015440
    Abstract: Light weight refractory aluminides, such as Al.sub.3 Nb and related aluminides may be produced from metallic powders by a high temperature exothermic reaction of refractory metals with molten aluminum. Mixtures of refractory metals and aluminum may be prepared and densified by powder metalurgy techniques. Applicant's process permits near net formations of stock shapes and parts by conducting the reaction in situ in a die.
    Type: Grant
    Filed: September 1, 1989
    Date of Patent: May 14, 1991
    Assignee: McDonnell Douglas Corporation
    Inventor: David M. Bowden
  • Patent number: 5015533
    Abstract: A member of selected shape embodying a refractory metal material such as a titanium aluminide preferably having reinforcing elements disposed therein is provided by combining constitutents of the refractory metal material surrounding the reinforcing elements, by consolidating the constituents and elements and forming them into the selected shape, and by reacting the constituents with each other for forming the refractory metal material in situ within the selected shape, at least one of the constituents also preferably being reacted in situ within the selected shape with metal material of the reinforcing elements for forming an intermetallic compound which securely holds the reinforcing elements in position within the selected shape.
    Type: Grant
    Filed: September 22, 1988
    Date of Patent: May 14, 1991
    Assignee: Texas Instruments Incorporated
    Inventors: Richard G. Delagi, George Trenkler
  • Patent number: 4992237
    Abstract: A process is provided for igniting a mixed powder material compact containing sufficient fuel to support an exothermic reaction between ingredients contained in the compact. The ignition is achieved in an inert atmosphere with an electric arc produced by an electrode without contacting the compact and thereby initiating the reaction.
    Type: Grant
    Filed: January 24, 1990
    Date of Patent: February 12, 1991
    Assignee: Amax Inc.
    Inventor: William A. May
  • Patent number: 4990180
    Abstract: A self-sustaining combustion synthesis process for producing hard, tough, lightweight, low exothermic potential product (LEPP)/high exothermic potential product (HEPP) composites is based on the thermodynamic dependence of adiabatic temperature and product composition on the stoichiometry of the LEPP and HEPP reactants. For lightweight products the composition must be relatively rich in the LEPP component. LEPP rich composites are obtained by varying the initial temperature of the reactants. The product is hard, porous material whose toughness can be enhanced by filling the pores with aluminum or other metal phases using a liquid metal infiltration process. The process can be extended to the formation of other composites having a low exothermic component.
    Type: Grant
    Filed: September 1, 1989
    Date of Patent: February 5, 1991
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Danny C. Halverson, Beverly Y. Lum, Zuhair A. Munir
  • Patent number: 4988480
    Abstract: The proposed invention is used for the manufacture from the obtained composite of cutting tools, hard alloy tooling, dies and other products. A method according to the invention involves preparing a mixture, compacting it, placing the mixture into a synthesis zone, igniting the mixture, with subsequent reaction of components of the mixture under combustion conditions. Then cure is carried out during a period ranging from about 0.1 seconds to about 0.5 hours, and the hot combustion products are compacted under pressure at an average pressure rise rate ranging from about 10 to about 2000 kgf/cm.sup.2.s, with subsequent cure of the compacted product under isobaric conditions to complete homogenization of the composite, with subsequent cooling thereof to obtain an end composite.
    Type: Grant
    Filed: August 23, 1990
    Date of Patent: January 29, 1991
    Inventors: Alexandr G. Merzhanov, Inna P. Borovinskaya, Alexandr N. Pitjulin, Viktor I. Ratnikov, Konstantin L. Epishin, Vadim L. Kvanin
  • Patent number: 4985202
    Abstract: A method is taught for the in-situ precipitation of second phase materials, such as ceramic or intermetallic particles, in a substantial volume fraction of solvent metal matrix. The invention involves the propagating reaction of the second phase-forming constituents in a solvent metal medium to provide a porous composite of finely-dispersed second phase particles in the metal matrix. Exemplary materials include titanium carbide or titanium diboride in an aluminum matrix.
    Type: Grant
    Filed: August 28, 1989
    Date of Patent: January 15, 1991
    Assignee: Martin Marietta Corporation
    Inventors: William C. Moshier, John M. Brupbacher, Leontios Christodoulou, Dennis C. Nagle
  • Patent number: 4977036
    Abstract: Workpieces are very rapidly diffusion coated by heating the packed workpieces at a rate that brings the workpieces to diffusion-coating temperature and then completing the diffusion coating, all in less than 50 minutes, then cooling. Workpiece can have top coating layer of aluminum flake covered by a layer of extremely fine alumina or silica in a magnesium chromate binder, to provide surface having roughness at least about 10 micro-inches smoother than before the top coating. Used aluminized jet engine hot section members can be reconditioned by a fluoridizing treatment that deoxidizes and also removes residual aluminizing, so that the members can then be repaired if necessary and re-aluminized.
    Type: Grant
    Filed: November 21, 1989
    Date of Patent: December 11, 1990
    Assignee: Alloy Surfaces Company, Inc.
    Inventor: Alfonso L. Baldi
  • Patent number: 4965044
    Abstract: The present invention relates to a method of sintering ceramics and ceramics obtained by said method. According to the present invention, the synthesis and sintering of ceramics can be simultaneously carried out by utilizing the reaction heat generated when at least one metallic element selected from metallic elements of IIb, IVb, Vb and VIb groups of the Periodic Table is combined with at least one nonmetallic element such as B, C N and Si without heat or by preliminarily heating the ceramics at temperatures remarkably lower than the usual sintering temperature ceramics thus-produced are superior in abrasion resistance and corrosion resistance.
    Type: Grant
    Filed: August 11, 1989
    Date of Patent: October 23, 1990
    Assignees: I. Sumitomo Electric Industries, Ltd., Yoshinari Miyamoto, Osamu Yamada, Mitsue Koizumi
    Inventors: Yoshinari Miyamoto, Osamu Yamada, Mitsue Koizumi, Osamu Komura, Eiji Kamijo, Masaaki Honda, Akira Yamakawa
  • Patent number: 4961902
    Abstract: A method for manufacturing ceramic/metal or ceramic/ceramic composite articles is disclosed. The articles can be useful for the production of aluminum in fused salt electrolysis cells, as armour plates for the protection against projectiles, cutting tools, or in abrasion resistance applications. The temperature slope of the process if optimized such that one of the reactants in the manufacturing proceeds through peritectic decomposition at a heating rate of low temperature increase for desirably uniform temperature distribution over the reaction mixture. Then the temperature increase is greatly elevated to obtain a reaction sintering condition for avoiding grain growth of undesired reaction products. Elevated temperature reaction sintering conditions can be maintained to decompose undesired components before they are entrapped by the reaction product.
    Type: Grant
    Filed: January 6, 1987
    Date of Patent: October 9, 1990
    Assignee: Eltech Systems Corporation
    Inventors: Thomas M. Clere, Gholamreza J. Abbaschian, Douglas J. Wheeler, Albert L. Barnes
  • Patent number: 4961901
    Abstract: In a process of manufacturing diaphragms, a layer of a difficulty flowable metal powder is applied to a support, a wire net is rolled onto the powder layer and the latter is compacted at the same time and the metal powder is fired at 800.degree. to 1500.degree. C. in an oxidizing atmosphere. In order to impart to the diaphragms a constant thickness, strength and density, the metal powder is uniformly distributed and applied as regards its bulk volume to the support and the powder layer is moved under a distributing roller rotating opposite to the direction in which the powder is fed.
    Type: Grant
    Filed: April 18, 1989
    Date of Patent: October 9, 1990
    Assignee: Metallgesellschaft AG
    Inventors: Heinz Wullenweber, Peter Kohl, Herbert Jung, Jorgen Borchardt, Wolfgang Bickle, Jurgen Braus, Hans-Joachim Hiedemann
  • Patent number: 4957421
    Abstract: Titanium and titanium alloy surfaces can be diffusion coated, and portions of the surface protected against such coating by localized powdered masking layer of about 43% titanium, aluminum in an amount equal to the aluminum content of the surface masked, as well as other metals in an amount about one-fifth of their content in the surface masked. Diffusion coating can be speeded by high heat input. Diffusion coating packs can be made with chemically reduced metal content of sludges. Diffusion aliminizing followed by caustic leaching to remove much of the diffused-in aluminum, yields catalytically and pyrophorically active porous surface that also accepts top coatings. Mixtures of aluminum powder with nickel and/or iron powders react when heated to form Raney-like product that can be leached to become pyrophoric, and when held on a metal foil or gauze web will adhere to the web so that leached product can be used as pyrophoric foil for decoying heat-seeking missiles.
    Type: Grant
    Filed: April 10, 1989
    Date of Patent: September 18, 1990
    Assignee: Alloy Surfaces Company, Inc.
    Inventor: Alfonso L. Baldi
  • Patent number: 4954314
    Abstract: 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: Grant
    Filed: February 7, 1990
    Date of Patent: September 4, 1990
    Assignee: Kawasaki Jukogyo Kabushiki Kaisha
    Inventors: Yukio Nishiyama, Junzo Fujioka, Haruki Hino, Yuji Matsuzaki, Masayuki Sakiyama, Minoru Yokoyama
  • Patent number: 4948676
    Abstract: The present invention provides a ceramic/metal composite material comprising cerium/aluminum mixed oxides as the ceramic phase and an alloy or intermetallic compond of cerium and at least one of aluminum, nickel, iron and cobalt as the metal phase. The ceramic phase may comprise interengaged crystal lattices of ceria and alumina. The material may be a self-sustaining body which may be used as substrate for a dimensionally stable anode in molten sale aluminum electrowinning cells, coated with a protective layer of cerium oxyfluoride in situ during electrolysis in molten cryolite containing cerium ions.
    Type: Grant
    Filed: February 15, 1989
    Date of Patent: August 14, 1990
    Assignee: Moltech Invent S.A.
    Inventors: Dominique Darracq, Jean-Jacques Duruz
  • Patent number: RE34180
    Abstract: Cemented carbide substrates having substantially A or B type porosity and a binder enriched layer near its surface are described. A refractory oxide, nitride, boride, and/or carbide coating is deposited on the binder enriched surface of the substrate. Binder enrichment is achieved by incorporating Group IVB or VB transition elements. These elements can be added as the metal, the metal hydride, nitride or carbonitride.
    Type: Grant
    Filed: September 9, 1988
    Date of Patent: February 16, 1993
    Assignee: Kennametal Inc.
    Inventors: Bela J. Nemeth, deceased, George P. Grab