Pretreatment Of Consolidated Powders Patents (Class 419/44)
  • Patent number: 5523049
    Abstract: A heat sink composed of thermally conductive particles dispersed in a monolithic structure having a continuous microstructure; and the method of forming a heat sink by molding the heat sink from a thermoplastic or epoxy material which has been filled with thermally conductive particles, debinding the molded heat sink and densifying the debound heat sink into a monolithic structure.
    Type: Grant
    Filed: November 1, 1994
    Date of Patent: June 4, 1996
    Assignee: Iowa State University Research Foundation, Inc.
    Inventors: Robert L. Terpstra, Barbara K. Lograsso, Iver E. Anderson, Jeffrey A. Moore
  • Patent number: 5470525
    Abstract: Tantalum anode pellets or tantalum powders are treated to remove carbon content (mostly attributable to binders used in pressing the powders to pellet form and/or sintering of the pellets) by an aqueous leach at 50.degree.-200.degree. F. in lieu of the conventional complex distillation/decomposition methods.
    Type: Grant
    Filed: July 1, 1994
    Date of Patent: November 28, 1995
    Assignee: H. C. Starck, Inc.
    Inventors: Terrance B. Tripp, Malcolm Shaw
  • Patent number: 5466414
    Abstract: A process for fabrication of sintered metal components having improved mechanical, physical and wear-resistent properties.
    Type: Grant
    Filed: September 1, 1994
    Date of Patent: November 14, 1995
    Assignee: TecSyn, Inc.
    Inventor: Bjorn O. A. Pettersson
  • Patent number: 5466311
    Abstract: A method of manufacturing an Ni--Al intermetallic compound matrix composite comprising steps of a) providing an aluminum powder, b) providing a reinforced material, c) providing a reducing solution containing a reducing agent and nickel ions to be reduced, d) adding the aluminum powder and the reinforced material into the reducing solution, and e) permitting the reducing agent to reduce the nickel ions to be respectively deposited on the aluminum powder and the reinforced material. Such method permits the Ni--Al, Ni--Al+B intermetallic compound matrix composite to be produced inexpensively/efficiently/fastly.
    Type: Grant
    Filed: February 10, 1994
    Date of Patent: November 14, 1995
    Assignee: National Science Council
    Inventors: Chen-Ti Hu, Wen-Chih Chiou
  • Patent number: 5460775
    Abstract: The invention provides aluminum sintered alloys with high dimensional accuracy and high density which are superior in mechanical and physical characteristics as well as wear resistance, and a method of producing such alloys not by plastic working but by atmospheric sintering with high economy. Rapidly solidified aluminum alloy powder resulting from solidifying aluminum alloy molten metal containing 0.4 to 4.0% by weight of Mg at a solidification rate of 10.sup.2 .degree. C./sec or more is press molded in the cold, after annealing in the temperature range of 250 to 450.degree. C. if necessary, and then the molded product is sintered by generating nitrogen compounds on the powder surface at atmospheric pressure with a nitrogen partial pressure of 0.8 atm or more and a steam partial pressure of 0.01 atm or less in which a reducing gas component has been added as a nitrogen-combining acceleration gas component by 0.01 atm or more. Thus, a nitrogen-combined aluminum sintered alloy containing 0.4 to 4.
    Type: Grant
    Filed: July 2, 1993
    Date of Patent: October 24, 1995
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Tetsuya Hayashi, Yoshinobu Takeda
  • Patent number: 5460776
    Abstract: The invention relates to a method of producing connected sintered articles obtained by breaking a unitary preform.It is characterized in that:a) a preform is pressed from powdered metals while imprinting in it a superficial groove (3) located in a plane for the purpose of subsequent breakage,b) this preform is presintered in order to consolidate it mechanically, the preform however remaining brittle,c) it is optionally compacted by recompression,d) recesses for the members for the mechanical connection of the final parts are optionally machined in this preform,e) this preform is broken into at least two parts,f) final sintering is carried out,g) the articles are cooled.The invention is applicable in particular to the production of connecting rods and connecting rod covers or of annular articles with or without an undercut (broken in the axial plane).
    Type: Grant
    Filed: October 26, 1994
    Date of Patent: October 24, 1995
    Assignee: Sintertech
    Inventors: Luc Ackermann, Henri Gueydan
  • Patent number: 5454998
    Abstract: A permanent magnet is provided which is comprised of, by atomic percent: 10-24% R; 2-28% boron, 0.1-18.12% hydrogen; and balance being M. R is at least one element selected from La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Y and Sc, and M is at least one metal selected from Fe, Co, Ni, Li, Be, Mg, As, Si, Ti, V, Cr, Mn, Cu, Zn, Ga Ge, Zn, Nb, Mo, Ru, Rh, Pd, Ag, Sb, Te, Hf, Ta, W, Re, Os, Ir, Pt, Au, and Bi. A process for producing the rare earth element-metal-hydrogen boron magnets is also disclosed wherein the magnetic materials are treated in an atmosphere having partial pressures of hydrogen containing gas at temperatures below the phase transformation temperature of the rare earth element-metal hydrides prior to sintering.
    Type: Grant
    Filed: February 4, 1994
    Date of Patent: October 3, 1995
    Assignee: YBM Technologies, Inc.
    Inventors: Jacob G. Bogatin, Andrey Belov
  • Patent number: 5445790
    Abstract: A process for densifying a powder metallurgical product comprising steps of preparing a powdery starting material, pre-sintering the powdery starting material at a relatively low temperature, executing a pore-eliminating process for eliminating pores resulting from the preceding step on the powdery starting material, and sintering the powdery starting material at a relatively high temperature. It is beneficial to produce a product having a large dimension, a desired shape, and excellent mechanical properties, and being appropriate for or capable of suffering any post-treatment.
    Type: Grant
    Filed: May 5, 1994
    Date of Patent: August 29, 1995
    Assignee: National Science Council
    Inventors: Chen-Ti Hu, Wen-Chih Chiou
  • Patent number: 5427734
    Abstract: The object of the invention is to provide a manufacturing method of a complex shaped R--Fe--B type sintered anisotropic magnet improved the moldability of injection molding and preventing the reaction between R ingredients and binder and controlled the degradation of magnetic characteristics due to residual carbon and oxygen. Utilizing the R--Fe--B type alloy powder or the resin coated said alloy powder, and methylcellulose and/or agar and water, instead of the usual thermoplastic binder, it is mixed and injection molded. The molded body is dehydrated by the freeze vacuum dry method to control the reaction between R ingredients and of the R--Fe--B alloy powder and water; furthermore, by administering the de-binder treatment in the hydrogen atmosphere, and sintering it after the dehydrogen treatment, residual oxygen and carbon in the R--Fe--B sintered body is drastically reduced, improving the moldability during the injection molding to obtain a three dimensionally complex shape sintered magnet.
    Type: Grant
    Filed: June 24, 1993
    Date of Patent: June 27, 1995
    Assignee: Sumitomo Special Metals Co., Ltd.
    Inventors: Osamu Yamashita, Masahiro Asano, Tsunekazu Saigo
  • Patent number: 5403542
    Abstract: Method of manufacturing a sintered carbonitride alloy comprising wet milling powders of forming binder phase containing Co, Ni and mixture thereof and powder forming hard constituents of nitrides and carbonitrides with Ti as the main component to a mixture with desired composition; compacting said mixture to form compact; heating the compact at 100-300 C. in oxygen or air and subjecting said compact in multiple heating steps to effect sintering.
    Type: Grant
    Filed: February 10, 1994
    Date of Patent: April 4, 1995
    Assignee: Sandvik AB
    Inventors: Gerold Weinl, Rolf G. Oskarsson, Per Gustafsson
  • Patent number: 5399438
    Abstract: Disclosed is a stainless steel member with a high corrosion resistance suitable for a structural member used in highly corrosive environments, such as an edge seal plate of a molten carbonate fuel cell. This stainless steel member includes a base material consisting of stainless steel containing chromium, and a corrosion-protective layer formed on the surface of the base material. In this corrosion-protective layer, a granular heterophase containing chromium is precipitated in an ordered alloy consisting of aluminum and the constituent elements of the base material.
    Type: Grant
    Filed: September 14, 1993
    Date of Patent: March 21, 1995
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroshi Tateishi, Kiyoshi Imai, Hideyuki Ohzu, Kazuaki Nakagawa, Yoshihiro Akasaka
  • Patent number: 5397531
    Abstract: Metal injection-molded green bodies (2) are formed from a granulated feedstock comprising metal powder and a binder comprising:a) 15-25 volume % paraffin waxb) 20-30 volume % microcrystalline waxc) 45-60 volume % polyethylene.The paraffin wax has two melting regions around 45.degree. C. and 63.degree. C. and the microcrystalline wax exhibits four melting regions in the range 62.degree. C. and 144.degree. C. By raising the temperature of the oven in a controlled manner, first the paraffin wax and then the microcrystalline wax melts and is vapourised and entrained in a flow of carrier gas which flows over supporting trays (5), as indicated by the horizontal arrows (a). The requirement for wicking powder is eliminated by the staged removal of the wax and the polyethylene can subsequently be removed at a higher temperature by thermal depolymerisation in the same apparatus.
    Type: Grant
    Filed: June 2, 1993
    Date of Patent: March 14, 1995
    Assignee: Advanced Materials Technologies Pte Limited
    Inventors: D. Dunstan H. Peiris, Jian G. Zhang
  • Patent number: 5387272
    Abstract: The present invention provides an Al-Si based sintered alloy of high strength and high ductility, a method for production thereof and use thereof. The alloy comprises 1-45% of Si, 0.1-20% of an element of Group IIIa, 0.01-5% of at least one element of Groups IVa and Va, the balance of substantially Al. This alloy can further contain at least one of 0.01-5% of Cu, 0.01-5% of Mg, 2.0% or less of Fe, 1.5% or less of Mn and 1.5% or less of Co and the oxygen content is reduced to 0.15% or less by sintering under vacuum. The present invention is applied to automobile parts such as a piston and scroll compressors. The alloy has a tensile strength of about 40 kg/mm.sup.2 or higher and an elongation of 1.5% or more at 150.degree. C.
    Type: Grant
    Filed: April 8, 1992
    Date of Patent: February 7, 1995
    Assignees: Hitachi, Ltd., Hitachi Powdered Metals Company, Limited
    Inventors: Yasuo Kamitsuma, Yusaku Nakagawa, Mitsuo Chigasaki, Tadashi Iizuka, Kooichi Inaba, Keiichi Nakamura, Masaki Minabe, Tsuyoshi Kagaya
  • Patent number: 5380482
    Abstract: A method of manufacturing ingots for use in making objects having heat, thermal shock, corrosion and wear resistance by formulating a composition of about 17-80% TiB.sub.2 powder, about 0.0 to 4.0% Y.sub.2 O.sub.3 powder, and the balance of NiAl powder, the powders being thoroughly admixed, and placing the admixture into a mold in which it is subjected to a pressure of about 7000 psi and a temperature of about 1400.degree. C. for 20 to 140 minutes in an inert atmosphere, after which the mold is cooled and the ingot is removed and ready for use in manufacturing an object. In some applications the use of a ceramic filler material mixed with the powder is employed to improve the physical characteristics of the finished ingot.
    Type: Grant
    Filed: April 2, 1993
    Date of Patent: January 10, 1995
    Assignee: Aspen Research, Inc.
    Inventors: David B. Maginnis, Frank Maginnis
  • Patent number: 5376329
    Abstract: A method of making a composite orifice having a tungsten core which is diffusion bonded to a molybdenum shell. Tungsten and molybdenum powders in contact with each other in a mold are isostatically pressed to form a pressed bonded composite part. The pressed, unsintered tungsten core portion of the part is then machined to the desired dimensions. The pressed composite part is then sintered to form a diffusion bonded composite orifice. The pressed and sintered molybdenum shell portion of the orifice may then be machined to the desired dimensions.
    Type: Grant
    Filed: November 16, 1992
    Date of Patent: December 27, 1994
    Assignee: GTE Products Corporation
    Inventors: Ricky D. Morgan, James A. Giffen, Jr.
  • Patent number: 5366688
    Abstract: A heat sink composed of metal particles dispersed in a binder or a sintered structure in which the binder is removed; and the method of forming a heat sink by molding the heat sink from a thermoplastic or epoxy material which has been filled with metal particles.
    Type: Grant
    Filed: March 10, 1994
    Date of Patent: November 22, 1994
    Assignee: Iowa State University Research Foundation, Inc.
    Inventors: Robert L. Terpstra, Barbara K. Lograsso, Iver E. Anderson, Jeffrey A. Moore
  • Patent number: 5344716
    Abstract: In accordance with a method of producing metal sinter bodies, the bodies are provided with degassing openings which are made preferably before sintering of an initial press body part.
    Type: Grant
    Filed: August 10, 1992
    Date of Patent: September 6, 1994
    Assignee: Firma Ernst Winter & Sohn GmbH & Co.
    Inventor: Dietrich Borse
  • Patent number: 5344605
    Abstract: The object is to provide a method of degassing or solidifying an aluminum alloy powder by utilizing an induction heating as a degassing means in a step of forming and solidifying an aluminum powder or aluminum alloy powder, whereby the disadvantages of the prior art can be overcome. The feature of the present invention consists in preforming an aluminum powder, aluminum alloy powder or aluminum composite alloy powder or mixed powders thereof with non-metallic grains to give a specific electric resistance of at most 0.2.OMEGA.cm, subjecting the preform directly to induction heating in an atmosphere at normal pressure, temperature-raising to 400.degree. to 600.degree. C. at a temperature gradient of at least 0.4.degree. C./sec in a temperature range of at least 300.degree. C. and removing heat-decomposable volatile components to obtain a hydrogen content of at most 10 ppm.
    Type: Grant
    Filed: September 21, 1993
    Date of Patent: September 6, 1994
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Toshihiko Kaji, Yoshinobu Takeda, Yuusuke Odani, Kiyoaki Akechi, Takao Tanji
  • Patent number: 5340532
    Abstract: A method for manufacturing a sintered body by a) forming a slurry comprising a powder mixture, a dispersant providing steric stabilization for the powders and an organic solvent with a possible addition of one or more soluble polymers; b) transferring the slurry into a mold; and c) changing the temperature sufficient to cause gelation of the sterically stabilized suspension to form a green body. The method also includes d) removing the green body from the mold; e) transferring the green body to a chamber where the gelation temperature can be maintained and the pressure decreased to facilitate removal of the solvent to form a dried body; f) heating the body for a time sufficient to substantially remove the dispersant from the body and; g) sintering the body. The sintered body can be an insert for metal cutting tools.
    Type: Grant
    Filed: April 23, 1993
    Date of Patent: August 23, 1994
    Assignee: Sandvik AB
    Inventor: Lennart Bergstrom
  • Patent number: 5338506
    Abstract: A process for making a non magnetic Ni-WC cemented carbide composition and articles made from the same. The process comprises:(a) dewaxing a green Ni-WC cemented carbide substrate in the presence of hydrogen gas at a pressure less than about 1000 torr and at a sufficient flow rate and a sufficient time to affect the saturation magnetization and magnetic permeability of the Ni-WC cemented carbide substrate;(b) pumping out the hydrogen gas and introducing argon at a pressure in the range of about 1 torr to 1000 torr;(c) increasing the temperature up to the sintering temperature to facilitate sintering of the Ni-WC cemented carbide substrate; and;(d) cooling the furnace to room temperature.The articles made according to this invention are useful as wear parts for electronic instruments and as punches form aluminum beverage cans.
    Type: Grant
    Filed: December 21, 1992
    Date of Patent: August 16, 1994
    Assignee: Valenite Inc.
    Inventors: John W. Friederichs, Prakash K. Mirchandani, Paul J. Krudy
  • Patent number: 5336465
    Abstract: A slurry compound prepared by a sintering powdery material and a binder is press-molded to obtain a contour for the final product applicable to a bone-implant such as hip prosthesis. The molded body is given a programmed movement of rotation and/or swinging to impart a centrifugal force to the sintering particles which direct toward the inner wall of the mold cavity. The final product obtained after sintering has a hollow interior having no communication to the outside. Imparting conditions of rotating/swinging movement may be changed or programmed in order to achieve a desired structure or constitution of the final product. By way of example, larger particles concentrate near the inner wall of the mold to provide a rough, porous surface of the body, whereas it has a dense core consisting mainly of sintered fine particles. A hip prosthesis having a ceramic-rich femoral head and a metal-rich stem may also be produced by so programming the movement imparting conditions.
    Type: Grant
    Filed: December 3, 1992
    Date of Patent: August 9, 1994
    Assignees: Janome Sewing Machine Co., Ltd., Terumo Corporation
    Inventors: Noboru Matsunaga, Kazuyoshi Azeyanagi, Ichirou Sogaishi, Takeo Katakura, Yoshihisa Ueda, Takaaki Ohsawa
  • Patent number: 5316718
    Abstract: A composite electrode for electrochemical processing having improved high temperature properties, and a process for making the electrode by combustion synthesis. A composition from which the electrode is made by combustion synthesis comprises from about 40% to about 90% by weight of a particulate or fibrous combustible mixture which, when ignited, is capable of forming an interconnected network of a ceramic or metal-ceramic composite, and from about 10% to about 60% by weight of a particulate or fibrous filler material capable of providing the electrode with improved oxidation resistance and maintenance of adequate electrical conductivity at temperatures above 1000.degree. C. The filler material is molybdenum silicide, silicon carbide, titanium carbide, boron carbide, boron nitride, zirconium boride, cerium oxide, cerium oxyfluoride, or mixtures thereof.
    Type: Grant
    Filed: June 14, 1991
    Date of Patent: May 31, 1994
    Assignee: Moltech Invent S.A.
    Inventor: Jainagesh A. Sekhar
  • Patent number: 5310520
    Abstract: Discrete powder particles of copper 14 and INVAR 12 are mixed together in a container 16 and packed into a powder metal article. This article is hot vacuum degassed and vacuum sealed and then heated to temperature well below the sintering temperature of copper or INVAR. Immediately after heating the article, it is subjected to a high pressure, high strain force such as extrusion through a die thereby yielding a fully dense, strong composite material 10 with excellent combined thermal expansion and conductivity properties.
    Type: Grant
    Filed: January 29, 1993
    Date of Patent: May 10, 1994
    Assignee: Texas Instruments Incorporated
    Inventors: Sunil C. Jha, James A. Forster, Henry F. Breit
  • Patent number: 5308556
    Abstract: A method of forming an extrusion die fabricated from sinterable ceramic or metal powders, for use in forming honeycomb monolith structures including machining of the die in the green state or after partial densification. Alternatively, all or part of the machining can be performed after full densification or sintering.
    Type: Grant
    Filed: February 23, 1993
    Date of Patent: May 3, 1994
    Assignee: Corning Incorporated
    Inventor: Rodney D. Bagley
  • Patent number: 5306463
    Abstract: A process for producing a structural member of an amorphous alloy, which includes the steps of subjecting a material formed from an amorphous alloy having a glass transition temperature Tg and a crystallization temperature Tx, which is higher than the glass transition temperature Tg, to a thermal treatment in which the material is kept at a heating temperature equal to or lower than the glass transition temperature Tg, thereby generating a structure relaxation phenomenon in the material, and subjecting the material to a hot plastic working while setting the hot working start temperature of the green compact at a level equal to or lower than the crystallization temperature Tx. In this process, the workability of the material can be improved to produce a high strength amorphous alloy structural member that has an increased volume fraction of an amorphous phase. Furthermore the generation of any defect due to gas inclusion is suppressed.
    Type: Grant
    Filed: April 19, 1991
    Date of Patent: April 26, 1994
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventor: Hiroyuki Horimura
  • Patent number: 5288454
    Abstract: A method for controlling the remanance of a sintered magnet by varying the time when the orienting field is applied during cold compression. The method comprises obtaining powders of an appropriate particle size, compressing the powders in an oriented field, sintering, heat treating, machining and magnetizing to technical saturation. The cold compressing in an orienting field takes place at a precompression rate of more than 15% before the orienting field is applied. The method applies to magnets of all shapes which must have magnetic induction well defined in modulus and in direction, particularly annular magnets for traveling wave tubes.
    Type: Grant
    Filed: January 6, 1993
    Date of Patent: February 22, 1994
    Assignee: Aimants Ugimag S.A.
    Inventors: Jean-Marc Lang, Robert Tissot
  • Patent number: 5286323
    Abstract: An dome-shaped extrusion die for use in forming honeycomb monolith structures is disclosed. The die is formed by deforming an extrusion die having a flat cross section to obtain a dome-shaped cross section. Alternatively, the die may be fabricated from sinterable ceramic or metal powders in which case the holes and slots may be formed either in the green state, or in a chalk-hard state after partial densification.
    Type: Grant
    Filed: February 23, 1993
    Date of Patent: February 15, 1994
    Assignee: Corning Incorporated
    Inventor: Rodney D. Bagley
  • Patent number: 5284615
    Abstract: The present invention presents a method of processing ferrous powder materials to produce small component parts exhibiting excellent soft magnetic properties, in particular, residual magnetic flux density. The processing steps involve, in part, mixing with a binder, dewaxing or presintering at a temperature higher than in the conventional dewaxing process, followed by final sintering and a further conversion sintering, at a temperature lower than in the conventional sintering process, to produce parts having density values of over 96% theoretical density and excellent soft magnetic properties. The invented method is suitable for producing small component parts having sufficient strength and excellent soft magnetic properties to make them suitable for miniaturized electrical and electronic equipment.
    Type: Grant
    Filed: July 15, 1992
    Date of Patent: February 8, 1994
    Assignee: Mitsubishi Materials Corporation
    Inventors: Koshiro Ueda, Mutsumi Moribayashi, Tohru Kohno
  • Patent number: 5284616
    Abstract: A method for the manufacture of objects from powdered material by isostatic or pseudo-isostatic pressing. A porous body (10), with open pores in contact with the external surface(s), is preformed from a powdered material, whereupon at least one layer (11, 12) of a powdered material is applied onto the external surface of the preformed porous body by dipping. The preformed porous body is covered with a casing (13) of glass, or a material which forms glass upon heating, arranged outside the intermediate layer (12). The casing is made impenetrable to the pressure medium by heating, whereupon the preformed body is compacted to an essentially dense body. The pore system of the preformed porous body is evacuated by applying a sub-atmospheric pressure by means of at least one suction cup (21) which is applied on the external surface to be coated in connection with and during the dipping of the body in a slurry (20) of powdered materials included in the layer (11, 12).
    Type: Grant
    Filed: February 10, 1992
    Date of Patent: February 8, 1994
    Assignees: ABB Cerama AB, Sandvik AB
    Inventors: Bertil Mattsson, Jan Nilsson, Marianne Collin
  • Patent number: 5262122
    Abstract: The disclosure relates to a method of binder removal from a green body before sintering or the like wherein the green body is initially heated to a temperature above the melting or flow point of the binder to liquify the binder and, at the elevated temperature, a small portion of the green body is brought into intimate contact with a non-supporting porous body of lower capillarity potential for the liquid binder. The liquid is drawn from all parts of the green body to the region of contact between the porous body and the green body and enters the body of lower capillarity potential preferentially, removing liquid from the green body through the surface of the green body only at said region of contact. The draining is continued with or without further increase in temperature until the green body is opened or becomes permeable.
    Type: Grant
    Filed: December 10, 1991
    Date of Patent: November 16, 1993
    Assignee: Witec Cayman Patents, Ltd.
    Inventor: Raymond E. Wiech, Jr.
  • Patent number: 5244510
    Abstract: This invention relates to a process for producing a rare earth-containing powder comprising crushing a rare earth-containing alloy in a passivating gas at a temperature from ambient temperature to a temperature below the phase transformation temperature of the material.Additionally, this invention relates to a process for producing a rare earth-containing powder compact comprising crushing a rare earth-containing alloy in water, compacting the crushed alloy material, drying the compacted alloy material at a temperature below the phase transformation temperature of the material, and treating the compacted alloy material with a passivating gas at a temperature from ambient temperature to a temperature below the phase transformation temperature of the material.Rare earth-containing alloys suitable for use in producing magnets utilizing the powder metallurgy technique, such as Nd-Fe-B and Sm-Co alloys, can be used.
    Type: Grant
    Filed: July 18, 1991
    Date of Patent: September 14, 1993
    Inventor: Yakov Bogatin
  • Patent number: 5183630
    Abstract: A process for producing a permanent magnet alloy based on a R--Fe--B--C system wherein R is at least one of the rare earth elements including Y, comprising the steps of preparing a molten crude alloy, producing a powder directly therefrom or after casting it into an alloy ingot and then grinding it into the powder, compacting the thus obtained powder and sintering the compacted product, the ingot or powder of the alloy before being sent to the compacting step being subjected to a heat treatment which is carried out at a temperature of 500.degree.-1,100.degree. C. for a period of 0.5 hour or more so as to produce a permanent magnet alloy based on an a R--Fe--B--C system whose individual magnetic crystal grains are covered with an oxidation-resistant protective film which has a C content higher than that of the individual crystal grains.
    Type: Grant
    Filed: June 4, 1991
    Date of Patent: February 2, 1993
    Assignee: Dowa Mining Co., Ltd.
    Inventors: Toshio Ueda, Yuichi Sato, Masayasu Senda, Seiji Isoyama, Seiichi Hisano
  • Patent number: 5152959
    Abstract: The present invention relates to a process for forming a composite strip material without any sintering step. The process includes blending a powdered high conductivity material such as powdered copper with a powdered low thermal expansion phase material such as a nickel-iron alloy, compacting the powders to form a green composite strip, heating the green strip to a hot rolling temperature and hot rolling the heated strip to a desired gauge. The heated strip is reduced less than about 45% to minimize the deformation of the low thermal expansion phase particles.
    Type: Grant
    Filed: June 24, 1991
    Date of Patent: October 6, 1992
    Assignee: AMETEK Speciality Metal Products Division
    Inventor: Clive R. Scorey
  • Patent number: 5129964
    Abstract: A process for preparing a permanent magnet is disclosed. The process comprises the steps of exposing material, in particulate form, and having an overall composition comprising 8 to 30 atomic percent of a first constituent selected from the group consisting of rare earth metals, 42 to 90 atomic percent of a second constituent selected from the group consisting of transition metals and 2 to 28 atomic percent of a third constituent selected from the group consisting of substances from Group III of the Periodic Table, to hydrogen gas under conditions such that hydrogen gas is absorbed by the material, exposing the hydrided material, in particulate form, to oxygen or an oxygen-containing gas in an amount and for a period of time sufficient to passivate the material, and compacting the material. Also disclosed are products from this process, namely, passivated, hydrided particles, alloy compacts formed of passivated, hydrided material and permanent magnets, having superior properties.
    Type: Grant
    Filed: September 6, 1989
    Date of Patent: July 14, 1992
    Assignee: SPS Technologies, Inc.
    Inventor: Richard L. Anderson
  • Patent number: 5126105
    Abstract: Method and apparatus for forming an improved missile warhead comprising a cap section, a center section, and a mounting section, the three sections forming a tubular body closed by the cap section at one end thereof, with a plurality of cavities formed on the inner circumference of the center section. In formation of the cavity-bearing missile body, a missile body preform is isostatically formed from powder material along with low-density inclusions, the latter being removed during later processing to form an array of cavities, relying upon differential material densification for release of the inclusions from the pressed preform.
    Type: Grant
    Filed: May 14, 1991
    Date of Patent: June 30, 1992
    Assignee: Industrial Materials Technology, Inc.
    Inventors: Joseph C. Runkle, Timothy D. Howard
  • Patent number: 5122326
    Abstract: The present invention is a method of removing binder material which is non-sublimable at room temperature and pressures greater than 1 Torr from a binder and particulate mixture. The binder and particulate mixture is formed into a shaped article and placed in a closed furnace. The closed furnace is then adjusted to a pressure and temperature sufficient to effect transformation of the binder material from a solid to a vapor and diffusion of the binder material as a vapor through, and from, the binder and particulate mixture without formation of a liquid phase of binder material on the binder and particulate mixture surface. The shaped article is held under these processing conditions until substantially all of the binder material transforms to its vapor state and diffuses through, and from, the mixture into the closed furnace. The binder material vapor is then evacuated from the furnace through conventional means.
    Type: Grant
    Filed: March 2, 1987
    Date of Patent: June 16, 1992
    Assignee: Vacuum Industries Inc.
    Inventors: Martha L. Jackson, Elliot Thompson
  • Patent number: 5122203
    Abstract: This invention relates to a process for producing a rare earth-containing material capable of being formed into a permanent magnet comprising crushing a rare earth-containing alloy and treating the alloy with a passivating gas at a temperature below the phase transformation temperature of the alloy. This invention further relates to a process for producing a rare earth-containing powder comprising crushing a rare earth-containing alloy in a passivating gas at a temperature from ambient temperature to a temperature below the phase transformation temperature of the material. This invention also relates to a process for producing a rare earth-containing powder comprising crushing a rare earth-containing alloy in water, drying the crushed alloy material at a temperature below the phase transformation temperature of the material, and treating the crushed alloy material with a passivating gas at a temperature from the ambient temperature to a temperature below the phase transformation temperature of the material.
    Type: Grant
    Filed: June 8, 1990
    Date of Patent: June 16, 1992
    Assignee: SPS Technologies, Inc.
    Inventor: Yakov Bogatin
  • Patent number: 5098620
    Abstract: A method and apparatus for injection molding of ceramic suspension is disclosed wherein an elastomeric bladder is disposed within a mold cavity of a mold. The elastomeric bladder, in a relaxed state, can be tubular or can be formed by bonding together sheets of material. A ceramic suspension is injected into the elastomeric bladder, whereby the elastomeric bladder is distended. Distention of the elastomeric bladder applied a significant force to the ceramic suspension for preventing jetting and formation of knit lines within the ceramic suspension. The ceramic suspension distends the elastomeric bladder until the mold cavity is filled. The ceramic suspension is then exposed to conditions sufficient to cause the injected ceramic suspension to form a molded ceramic greenware composite. The molded ceramic greenware composite can then be removed from the mold for drying and for debindering and densification to form a finished ceramic part.
    Type: Grant
    Filed: June 7, 1990
    Date of Patent: March 24, 1992
    Assignee: The Dow Chemical Company
    Inventors: Norbert L. Bradley, Virgil W. Coomer
  • Patent number: 5080846
    Abstract: A polyacetal binder is removed from an extruded or injection molded ceramic green body in less than 25 hours by a variable heating rate schedule in which the heating rate is reduced when the temperature of the green body reaches the point at which isothermal degradation of the polyacetal binder can take place and wherein at least 80 wt. % of the binder can be removed. In air, the isothermal removal of the binder can take place within the range of 160.degree.-220.degree. C. while in nitrogen the range is from about 300.degree.-360.degree. C.
    Type: Grant
    Filed: November 13, 1989
    Date of Patent: January 14, 1992
    Assignee: Hoechst Celanese Corp.
    Inventors: Hongkyu Kim, Gerd Wingefeld
  • Patent number: 5041261
    Abstract: A method for manufacturing a dense cermet article including about 80-95% by volume of a granular hard phase and about 5-20% by volume of a metal binder phase. The hard phase is (a) the hard refractory carbides, nitrides, carbonitrides, oxycarbides, oxynitrides, carboxynitrides, borides, and mixtures thereof of the elements selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, and B, or (b) the hard refractory carbides, nitrides, carbonitrides, oxycarbides, oxynitrides, and carboxynitrides, and mixtures thereof of a cubic solid solution of Zr--Ti, Hf--Ti, Hf--Zr, V--Ti, Nb--Ti, Ta--Ti, Mo--Ti, W--Ti, W--Hf, W--Nb, or W--Ta. The binder phase is a combination of Ni and Al having a Ni:Al weight ratio of from about 85:15 to about 88:12, and 0-5% by weight of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Co, B, and/or C. The method involves presintering the hard phase/binder phase mixture in a vacuum or inert atmosphere at about 1475.degree.-1675.degree. C., then HIPing at about 1575.degree.-1675.degree. C.
    Type: Grant
    Filed: December 21, 1990
    Date of Patent: August 20, 1991
    Assignee: GTE Laboratories Incorporated
    Inventors: Sergej T. Buljan, Helmut Lingertat, Steven F. Wayne
  • Patent number: 5028367
    Abstract: A process for making molded objects utilizes powder injection molding techniques. Powder is mixed with a binder and then cast into a compact. The compact is then subjected to a first debinding step in the presence of a wicking agent under gentle heating. In this first stage, at least 40% of the binder is removed. Additional binder is then removed in a subsequent higher temperature stage to produce a compact which is free of binder and free of cracks.
    Type: Grant
    Filed: December 8, 1989
    Date of Patent: July 2, 1991
    Assignee: Rensselaer Polytechnic Institute
    Inventors: Tai-Shing Wei, Randall M. German
  • Patent number: 4891182
    Abstract: A process for making a porous mass of a metal of iron- or titanium-group comprises steps of forming a sinter of solvent-soluble particles, pressing in a molten metal of the iron- or titanium- group into open interstices in the sinter, and eluting the particles from the composite of the sinter and metal. Solvent-soluble magnesia particles whose surface is either covered or not with a film of boric anhydride or solvent-soluble calcia particles whose surface is either covered or not with film of calcium chloride are sintered and machined into the desired shape. The formed sinter is put in a case of a heat-insulating material that can withstand the melting temperature of a metal of iron- or titanium-group. After being heated to a given temperature together with the case, the sinter is immediately put in a metal mold where a molten metal of iron- or titanium-group is pressed into open interstices in the sinter. Then, only the particles are eluted from the sinter-metal composite by a solvent.
    Type: Grant
    Filed: March 20, 1989
    Date of Patent: January 2, 1990
    Assignee: Agency of Industrial Science & Technology
    Inventors: Michiru Sakamoto, Akira Kitahara, Hidetoshi Ueno, Sumio Nagata
  • Patent number: 4879091
    Abstract: This invention relates to substantially full-dense, near-net shape bodies made of dispersion strengthened copper (D.S.C.) powder and products which are cold formed and/or machined from these bodies, such as resistance welding electrodes. The invention includes processes for manufacturing substantially full-dense, near-net shape, substantially equiaxed bodies from D.S.C. powder.
    Type: Grant
    Filed: December 14, 1987
    Date of Patent: November 7, 1989
    Assignee: SCM Metal Products, Inc.
    Inventors: Prasan K. Samal, Anil V. Nadkarni
  • Patent number: 4869869
    Abstract: A method of treating a preform consisting essentially FeNeB alloy particles to produce a magnet having superior magnetic properties, the steps:(a) removing O.sub.2 from the preform and applying an O.sub.2 resistant coating to the preform surface, or removing O.sub.2 and maintaining an O.sub.2 -free environment,(b) heating the coated preform to elevated temperature and in a non-oxidizing atmosphere, to facilitate subsequent bonding of the particles during their consolidation,(c) providing a consolidation zone containing a grain bed and transferring the heated and coated or uncoated preform to said zone to be embedded in the grain bed,(d) applying pressure to the grain bed sufficient to be transferred via the bed and to the heated preform, thereby to consolidate the preform.
    Type: Grant
    Filed: September 26, 1988
    Date of Patent: September 26, 1989
    Assignee: Ceracon, Inc.
    Inventors: Raymond L. Anderson, Joanna R. Groza, Brian Oslin
  • Patent number: 4839085
    Abstract: A method of manufacturing high-zirconium getters that involves hydrogen pulverization of an entire alloy ingot or ingot pieces. The method offers distinct advantages over techniques that use mechanical means of powder production. The method is useful expecially in the manufacture of tough porous getters, of high Zr-content Zr-V alloys that have minor additions of elements such as Fe, Ni, Mn and/or Al.
    Type: Grant
    Filed: November 30, 1987
    Date of Patent: June 13, 1989
    Assignee: Ergenics, Inc.
    Inventors: Gary D. Sandrock, Winfred L. Woodward, III
  • Patent number: 4839138
    Abstract: To make a sintered molding which is provided with at least one molybdenum containing wear-resisting facing (2), a low-alloy iron powder (10) which is intended to form the base of the molding and a carbon-free metal powder mixture (3) which is intended to form the wear-resisting facing (2) and consists of unalloyed iron particles and unalloyed molybdenum particles are jointly molded in a common mold (9) to form a molding, which is subsequently sintered.In order to prevent a mixing of the two metal powder layers, the metal powder which is intended to form the wear-resisting facing (2) is separately compacted to form a compact (5) before the mold (9) is charged with the iron powder (10) that is intended to form the base of the molding.
    Type: Grant
    Filed: March 10, 1988
    Date of Patent: June 13, 1989
    Assignee: Miba Sintermetall Aktiengesellschaft
    Inventor: Friedrich Filz
  • Patent number: 4820481
    Abstract: An improved method for the continuous fabrication of metal-hydride, electrochemical, hydrogen storage alloy, negative electrodes for use in rechargeable nickel metal hydride cells. The improved method comprises the steps of providing measured amounts of powdered metal hydride electrochemical hydrogen storage alloy material and disposing said material upon a continuous wire mesh screen substrate. Thereafter, the powdered metal hydride electrochemical hydrogen storage alloy and wire mesh screen are subjected to a compaction process wherein they are rolled and pressed so as to form a single integral electrode web which is subsequently exposed to a high temperature sintering process in a chemically inert environment. The sintering process is designed to drive off excess moisture in the material while discouraging oxidation of the electrode web and set the electrode web state of charge.
    Type: Grant
    Filed: April 25, 1988
    Date of Patent: April 11, 1989
    Assignee: Energy Conversion Devices, Inc.
    Inventors: Merle Wolff, Mark A. Nuss, Michael A. Fetcenko, Andrea L. Lijoi
  • Patent number: 4808224
    Abstract: A method of treating a preform consisting essentially FeNeB alloy particles to produce a magnet having superior magnetic properties, the steps:(a) removing O.sub.2 from the preform and applying an O.sub.2 resistant coating to the preform surface, or removing O.sub.2 and maintaining an O.sub.2 -free environment,(b) heating the coated preform to elevated temperature and in a non-oxidizing atmosphere, to facilitate subsequent bonding of the particles during their consolidation,(c) providing a consolidation zone containing a grain bed and transferring the heated and coated or uncoated preform to said zone to be embedded in the grain bed,(d) applying pressure to the grain bed sufficient to be transferred via the bed and to the heated preform, thereby to consolidate the preform.
    Type: Grant
    Filed: September 25, 1987
    Date of Patent: February 28, 1989
    Assignee: Ceracon, Inc.
    Inventors: Raymond L. Anderson, Joanna R. Groza, Brian Oslin
  • Patent number: 4769211
    Abstract: A process for the passivating, multistage compaction of hot iron particles supplied in the form of a packed bed from a reduction unit and for the subsequent breaking apart of the compacted iron band is described. Prior to the final compacting, the iron particles pass through a homogenizing and precompressing stage. Thus, the compacted iron has a pore volume of max. 40% and a density of at least 5.5 g/cm.sup.3. The iron compacted to a band is subsequently guided between the rollers (7,8,11) of a separating stage exposing it to bending stresses such that it breaks apart at the predetermined desired breaking points. The latter have a smaller density than the band regions between them. They can be produced in that in the precompression stage the feed speed is briefly decelerated compared with the feed speed in the compaction stage or in the compaction stage there is less marked compression at these points than in the intermediate regions.
    Type: Grant
    Filed: August 27, 1987
    Date of Patent: September 6, 1988
    Assignee: Korf Engineering GmbH
    Inventor: Klaus Langner
  • Patent number: 4743425
    Abstract: A method of producing ferrous sintered alloys comprises the steps of preparing mixed alloy powder containing Fe-P-C eutectic alloy powder which includes phosphorus within the range of 2.0% to 3.0% by weight, carbon not more than 4.0% by weight and one of molybdenum within the range of 8.0% to 11.0% by weight and boron within the range of 0.5% to 3.0% by weight, graphite, and ferroalloy powder containing chromium within the range of 11% to 14% by weight; causing the mixed alloy powder to be subjected to compression molding to have a green compact; and sintering the green compact to have a ferrous sintered alloy containing compound carbides in a matrix structure thereof. The graphite is so selected that the sum total of the graphite and the carbon included in the Fe-P-C eutectic alloy powder constitutes a part within the range of 5% to 8% by weight of the sum total of the graphite and the Fe-P-C eutectic alloy powder.
    Type: Grant
    Filed: September 3, 1987
    Date of Patent: May 10, 1988
    Assignees: Mazda Motor Corporation, Kawasaki Steel Corp.
    Inventors: Shigemi Ohsaki, Sumio Kamino, Minoru Nitta