Controlled Cooling After Sintering Patents (Class 419/25)
  • Patent number: 5108492
    Abstract: It is provided a method for the manufacture of a corrosion-resistant sintered alloy steel, which comprises providing a stainless steel powder; adding a binder to said steel powder; molding the mixture; and carrying out the steps of (1) heating the resultant molding to remove the binder therefrom, (2) sintering the thus debound molding under reduced pressure up to 30 Torr, and (3) further sintering at a higher temperature than those of steps (1) and (2) in a non-oxidative atmosphere under substantially atmospheric pressure. It is also provided a corrosion-resistant sintered alloy steel which comprises a stainless steel, said alloy steel having a density ratio of not less than 92%, a maximum diametric of pore present in the structure of not larger than 20 .mu.m, and a content of Cr at the surface of the steel as being sintered which is not less than 80% of a content of Cr in the inside thereof.
    Type: Grant
    Filed: February 22, 1990
    Date of Patent: April 28, 1992
    Assignee: Kawasaki Steel Corporation
    Inventors: Yoshisato Kiyota, Hiroshi Ohtsubo, Junichi Ohta, Masakazu Matsushita, Ichio Sakurada
  • Patent number: 5091022
    Abstract: There is disclosed a method for manufacturing intricate shaped magnetic parts having excellent soft magnetic characteristics which includes forming powders of Fe and P having particle sizes less than 45 .mu.m; mixing 0.1 to 1.0% by weight P powder with Fe powder; adding a binder; injection-molding the mixture at 1200 kg/cm.sup.2 ; removing the binder by heating; sintering the binder free part at 1200.degree.-1400.degree. C. for 30-180 min; and cooling the sintered part at a rate of less than 50.degree. C./min.
    Type: Grant
    Filed: July 19, 1990
    Date of Patent: February 25, 1992
    Assignee: Sumitomo Metal Mining Company, Limited
    Inventors: Masakazu Achikita, Akihito Ohtsuka
  • Patent number: 5077272
    Abstract: A preparation method of bulk YBa.sub.2 Cu.sub.3 O.sub.x superconductors with high transport critical current and critical current density (Jc), wherein x is 7-.delta., obtained by a modified melt-textured growth method. A continuous dc current carrying capacity exceeding 120 A with critical current density, Jc, higher than 37300 A/cm.sup.2 at 77K has been obtained for the prepared superconductor.
    Type: Grant
    Filed: April 27, 1990
    Date of Patent: December 31, 1991
    Assignee: Industrial Technology Research Institute
    Inventors: Kouth Chen, W. H. Lee
  • Patent number: 5069869
    Abstract: A process for shaping penetrating projectiles useful in the manufacture of military ammunition, comprising: preparing an alloy of tungsten, nickel, iron and copper by powder metallurgy, compacting the alloy mass into a rough shaped blank having an axis of revolution, sintering the rough shaped blanks thereby producing a blank having a density of at least 17,000 kg/m.sup.3, and work-hardening the sintered blank at a temperature ranging from ambient temperature to 500.degree. C., thereby producing a blank having a variable degree of reduction in section in a direction parallel to the axis of the blank.
    Type: Grant
    Filed: May 3, 1991
    Date of Patent: December 3, 1991
    Assignee: Cime Bocuze
    Inventors: Jean-Claude Nicolas, Raymond Saulnier
  • Patent number: 5041416
    Abstract: A superconductor metal matrix composite formable into an electrical current carrying material. A superconductive particulate is intermixed with a normal metal matrix, pressed into form and heated to form the composite. The metal matrix surrounds the superconductive particulate to prevent loss of oxygen from the superconductive particulate so the particulate retains its superconductive properties. The metal matrix also becomes superconductive due to proximity effect.
    Type: Grant
    Filed: October 16, 1990
    Date of Patent: August 20, 1991
    Assignee: FMC Corporation
    Inventor: Charles N. Wilson
  • Patent number: 5032355
    Abstract: A method of manufacturing a sintering product of Fe-Co alloy soft magnetic material by molding a powder comprising from 40 to 60% by weight of Co and the substantial balance of Fe, sintering the molding product and then applying heat treatment, wherein cooling after the heat treatment is conducted as slow cooling at a cooling rate of not more than 50.degree. C./min.
    Type: Grant
    Filed: October 1, 1990
    Date of Patent: July 16, 1991
    Assignee: Sumitomo Metal Mining Company Limited
    Inventors: Masakazu Achikita, Akihito Ohtsuka, Shinichi Sogame
  • Patent number: 4999050
    Abstract: This invention relates generally to materials and processes for making materials and, more particularly, to high performance boride dispersion strengthened materials, including alloy-modified, boride dispersion strengthened materials and techniques for making such materials.
    Type: Grant
    Filed: August 30, 1988
    Date of Patent: March 12, 1991
    Assignee: Sutek Corporation
    Inventors: Luis E. Sanchez-Caldera, Arthur K. Lee, Nam P. Suh, Jung-Hoon Chun
  • 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: 4979984
    Abstract: A process is claimed for the manufacture of an insert. The process includes the steps of filling a die cavity defined by a die mold with powdered metal, the die cavity conforming to the required shape of the insert. The powdered metal is compressed within the die cavity such that a compact of the insert is formed within the die cavity. The compact is sintered within a sintering furnace so that a first porton of the compact is in the solid phase and a second portion of the compact is in the liquid phase. The compact is rapidly cooled within the sintering furnace to a temperature below the melting point of the powdered metal. Such temperature is maintained so that densification of the first portion to substantially full density is achieved. The arrangement is such that the profile integrity of the compact is retained. the resltant insert is then subsequently cooled.
    Type: Grant
    Filed: March 16, 1990
    Date of Patent: December 25, 1990
    Assignee: Inserts Ltd.
    Inventor: Linwood R. Anderson
  • Patent number: 4976916
    Abstract: A method for producing a ferrous sintered alloy product available for a vane used in a rotary compressor. The method comprises the steps of preparing metal powder mixture primarily containing iron, compacting the powder mixture to obtain a powder compact, sintering the powder compact to obtain a sintered body, subjecting sub-zero treatment to the sintered body, and tempering the sintered body. The sintered alloy product is used as a vane slidably disposed in a vane groove of the rotary compressor whose cooling medium is maintainable without deterioration of its property.
    Type: Grant
    Filed: May 26, 1989
    Date of Patent: December 11, 1990
    Assignee: Nippon Piston Ring Co., Ltd.
    Inventor: Soichi Shimomura
  • Patent number: 4973355
    Abstract: The invention relates to sintered hard metals having high cutting properties, particularly plastic deformation resistance at high temperatures, crater resistance and the like, suitable for use as cutting tools, wear resistant tools and materials for dies, and the method for producing the same. The invention has for an object to obtain both sintered hard metals having the aforesaid high properties by sintering metallic components comprising IVa group metals, VIa group metals or metals of both groups substituted by Va group metals up to 60 mol % respectively, a B-1 type solid solution hard phase consisting of non-metallic components of C, N and O, and a metallic bonding phase, in a CO gas atmosphere, and to sintered hard metals in which an uniform hardness is imparted to the surface and interior thereof by the method of sintering the said sintered hard metal in a CO gas atmosphere.
    Type: Grant
    Filed: October 31, 1988
    Date of Patent: November 27, 1990
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kunihiro Takahashi, Toshio Nomura, Takaharu Yamamoto
  • Patent number: 4970049
    Abstract: Sintered ferrous materials are described having a composition in wt % lying within the ranges of C 0.8-1.5/W 1-4.4/Mo 1-4.4/V 1-2.6/Cr 1.3-3.2/Others 3 max./Fe balance. The material may be made by a method comprising the steps of mixing between 40 and 70 wt % of a powder having a composition in wt % within the ranges C 0.45-1.05/W 2.7-6. 2/Mo 2.8-6.2/V 2.8-3.2/Cr 3.8-4.5/Others 3.0 max./Fe balance with between 60 and 30 wt % of an iron powder and from 0.4 to 0.9 wt % of carbon powder, pressing a green body of the article from the mixed powder and then sintering the green body. The material may optionally contain sulphur, metallic sulphides. The material may be infiltrated.
    Type: Grant
    Filed: October 6, 1988
    Date of Patent: November 13, 1990
    Assignee: Brico Engineering Limited
    Inventors: Andrew R. Baker, Richard L. Kettle
  • Patent number: 4968347
    Abstract: A high energy rare earth-ferromagnetic metal permanent magnet is disclosed which is characterized by improved intrinsic coercivity and is made by forming a particulate mixture of a permanent magnet alloy comprising one or more rare earth elements and one or more ferromagnetic metals and forming a second particulate mixture of a sintering alloy consisting essentially of 92-98 wt. % of one or more rare earth elements selected from the class consisting of Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and mixtures of two or more of such rare earth elements, and 2-8 wt. % of one or more alloying metals selected from the class consisting of Al, Nb, Zr, V, Ta, Mo, and mixtures of two or more of such metals. The permanent magnet alloy particles and sintering aid alloy are mixed together and magnetically oriented by immersing the mixture in an axially aligned magnetic field while cold pressing the mixture.
    Type: Grant
    Filed: November 22, 1988
    Date of Patent: November 6, 1990
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Ramamoorthy Ramesh, Gareth Thomas
  • Patent number: 4964908
    Abstract: Sintered ferrous alloys of at least 90% theoretical density are obtained by sintering a powder mixture containing atomized copper-free ferrous slloy, copper phosphide and, optionally, copper, copper alloy and/or graphite to provide a sintered alloy containing, in percentages by weight, 0.6-2.5% carbon, 2-8% chromium, 4.2-20% copper, 0.5-10% molybdenum, 0.4-1.2 % phosphorus, 1-20% tungsten, 1-5% vanadium, and optionally, up to 12% cobalt, up to 2% manganese and up to 2% nickel and the balance being iron and less than 2% impurities. The % carbon content is in the range CCC % -0.1% to CCC % +0.3% (where CCC % is the calculated carbon content =(CWE/20)-0.4 and CWE=% tungsten content +twice % molybdenum content +six times % vanadium content) and the copper phosphide contains 2 to 14% phosphorus. The sintered compact is cooled at a rate which prevents hardening and can subsequently be machined and/or heat treated.
    Type: Grant
    Filed: July 21, 1989
    Date of Patent: October 23, 1990
    Assignee: Manganese Bronze Limited
    Inventor: Geoffrey Greetham
  • Patent number: 4956336
    Abstract: A superconductor material having a current density, J, of from about 30,000 to about 85,000 amps/cm.sup.2 at zero magnetic field and 77.degree. K. is disclosed. The 123 superconductor is of the formula L.sub.1 Ba.sub.2 Cu.sub.3 O.sub.6 +.delta. wherein L is preferably yttrium. The process comprises compacting the solid state reaction product of L.sub.1 Ba.sub.2 Cu.sub.3 O and then sintering the reaction product at a temperature between about 40.degree. C. to about 90.degree. C. below its melting point, i.e., for Y.sub.1 Ba.sub.2 Cu.sub.3 O.sub.6 +.delta. at a temperature of approximately 940.degree. C. The composition is then heated in a preheated chamber maintained at approximately 1090.degree. C. to about 1,200.degree. C. (approximately 1,100.degree. C. for Y.sub.1 Ba.sub.2 Cu.sub.3 O.sub.6 +.delta.) until it has been decomposed, and is then rapidly cooled to a temperature between about 10.degree. C. to about 30.degree. C. above its melting point, i.e. for Y.sub.1 Ba.sub.2 Cu.sub.3 O.sub.6 +.delta.
    Type: Grant
    Filed: February 10, 1989
    Date of Patent: September 11, 1990
    Assignee: University of Houston - University Park
    Inventors: Kamel Salama, Venkatakrishnan Selvamanickam
  • Patent number: 4933139
    Abstract: A process for the production of at least a one kilogram block of Chevrel-phase Pb.sub.x Mo.sub.y S.sub.z, wherein x=0.9 to 1.2, y=6.0 to 6.4, and z=7 to 8, includes mixing thoroughly stoichiometric quantities of starting materials in powdered form. The starting materials are selected from elemental Pb, Mo and S, sulfides of elemental Pb and Mo, and mixtures thereof. The starting mixture is introduced into a metallic container and evacuated to a pressure to 10.sup.4 Pa or less. The evacuated container is subjected to hot isostatic pressing at a constant pressure selected from a pressure ranging from 100 to 300 MPa, at a heating rate ranging from 10.degree. to 100.degree. C./hr., at a final pressing temperature ranging from 800.degree. to 1200.degree. C., and for a pressing period ranging from 10 to 100 hours, whereby the starting materials react to form the block of Chevrel-phase Pb.sub.x Mo.sub.y S.sub.z. The block is cooled at a cooling rate ranging from 50.degree. to 500.degree. C./hr.
    Type: Grant
    Filed: September 1, 1987
    Date of Patent: June 12, 1990
    Assignee: Kernforschungszentrum Karlsruhe GmbH
    Inventors: Rene Flukiger, Wilfried Goldacker
  • Patent number: 4931253
    Abstract: A method for producing a titanium alloy powder metallurgy article having high resistance to loading and creep at high temperature is described and comprises the steps of simultaneously pressing a preselected quantity of titanium alloy powder at from 15 to 60 ksi and heating the powder to a temperature just below the beta transus temperature of the alloy to promote beta to alpha phase transformation in the alloy, and then slowly cooling the compacted powder under pressure.
    Type: Grant
    Filed: August 7, 1989
    Date of Patent: June 5, 1990
    Assignee: United States of America as represented by the Secretary of the Air Force
    Inventors: Daniel Eylon, Francis H. Froes, Gerhard Welsch
  • Patent number: 4923671
    Abstract: Method of producing powder-metallurgical objects, specifically elongate objects such as rods, sections, tubes or the like, wherein a powder of metal and/or metal alloys of great hardness, particularly tool steel or high-speed steel powder, is charged into a thin-walled capsule, said capsule is then sealed so as to be airtight, is heated, and subjected to isostatic compression to produce a blank which will then undergo hot-working, specifically extrusion, for the production of the finished product. In a first alternative, the airtight and sealed capsule is initially heated to a temperature higher than 1,000.degree. C. Following through-heating of the capsule, the latter is maintained at an elevated temperature for a prolonged period. Then the capsule is slowly cooled and subjected to cold isostatic compression prior to final shaping. In a second alternative, the capsule is sealed so as to be airtight, and then subjected to an initial cold isostatic compression.
    Type: Grant
    Filed: February 6, 1989
    Date of Patent: May 8, 1990
    Inventor: Christer Aslund
  • Patent number: 4923513
    Abstract: A carefully controlled amount of hydrogen is diffused into titanium or its alloys at an elevated temperature above the transformation temperature. After the elevated temperature is maintained for an approprate duration of time, eutectoid transformation is performed in an inert atmosphere, again for an appropriate period of time, during which or alternatively after which the hydrogen is removed and the metal cooled to room temperature. A sintered titanium alloy component of the type intended for use as a joint replacement subjected to such a treatment displays a fatigue strength which is noticeably improved over a similar article with an equiaxed or lamellar microstructure.
    Type: Grant
    Filed: April 21, 1989
    Date of Patent: May 8, 1990
    Assignee: Boehringer Mannheim Corporation
    Inventors: Paul Ducheyne, David H. Kohn
  • Patent number: 4921666
    Abstract: A process for high efficiency hot isostatic pressing in a hot isostatic pressing treatment for sintering or densifying a ceramic or metallic work in a high temperature and high pressure gas atmosphere, comprising preheating the work outside a high pressure vessel prior to the hot isostatic pressing treatment, transferring the preheated work as surrounded with the gas in a hot state into the high pressure vessel, then treating the work at high temperature and high pressure in a gas atmosphere, thereafter taking out the work from the high pressure vessel together with the gas atmosphere, then cooling the work if necessary, and subsequently taking it out from the gas atmosphere, as well as an apparatus for practicing the above process, wherein a treating chamber for effecting the hot isostatic pressing treatment is covered with a hermetic casing, and at least one valve mechanism capable of providing communication and cut-off between the interior and exterior of the treating chamber is provided in each of upper a
    Type: Grant
    Filed: November 29, 1984
    Date of Patent: May 1, 1990
    Assignee: Kabushiki Kaisha Kobe Seiko Sho
    Inventor: Takahiko Ishii
  • Patent number: 4911989
    Abstract: A coated cemented carbide alloy having jointly a high toughness and high wear resistance is produced by specifying the cooling rate during sintering in efficient manner, which alloy comprises a cemented carbide substrate consisting of a hard phase of at least one member selected from the group consisting of carbides, nitrides and carbonitrides of Group IVa, Va and VIa metals of Periodic Table and a binder phase consisting of at least one member selected from the iron group metals, and a monolayer or multilayer, provided thereon, consisting of at least one member selected from the group consisting of carbides, nitrides, oxides and borides of Group IVa, Va and VIa metals of Periodic Table, solid solutions thereof and aluminum oxide, in which the hardness of the cemented carbide substrate in the range of 2 to 5 .mu.m from the interface between the coating layer and substrate is 800 to 1300 kg/mm.sup.
    Type: Grant
    Filed: April 10, 1989
    Date of Patent: March 27, 1990
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Nakano Minoru, Tobioka Masaaki, Nomura Toshio
  • Patent number: 4911625
    Abstract: This case relates to tough, wear resistant graded structure composites, to a process for preparing the same and to tools and products fabricated therefrom. The composites have a surface layer e.g. of WC and a binder, an interface layer, e.g. which is a stepwise transition from the surface layer whereby the binder content thereof gradually increases, a substrate layer which is a combination of e.g. an initial high carbon steel layer and finally a base layer of bainitic steel. The composites are substantially non-porous and can be used to fabricate components such as drill bits, wear plates, pump components machine tools, seals, washers, bearings and the like.
    Type: Grant
    Filed: May 17, 1989
    Date of Patent: March 27, 1990
    Assignee: The British Petroleum Company, p.l.c.
    Inventors: Alan R. Begg, Colin W. Brown, Neil E. S. Charman
  • Patent number: 4909841
    Abstract: A process of hot pressing of materials to form articles or compacts is characterized by the steps: (A) providing a compactable particulate mixture; (B) uniaxially pressing the particles without heating to provide article or compact (22); (C) placing at least one article or compact (22) in an open pan (31) having an insertable frame (32) with edge surfaces (34) that are not significantly pressure deformable, where the inside side surfaces of the frame are parallel to the central axis B--B of the open pan, and where each article or compact is surrounded by fine particles of a separating material; (D) evacuating air from the container and sealing the articles or compacts inside the container by means of top lid (36); (E) hot pressing the compacts at a pressure from 352.5 kg/cm.sup.2 to 3,172 kg/cm.sup.
    Type: Grant
    Filed: June 30, 1989
    Date of Patent: March 20, 1990
    Assignee: Westinghouse Electric Corp.
    Inventors: Natraj C. Iyer, Alan T. Male, William R. Lovic
  • Patent number: 4904537
    Abstract: An improved process and an improved composite bearing material produced thereby comprising a hard metal backing strip having leaded-bronze bearing lining tenaciously bonded to at least one face surface thereof and wherein the bearing lining is characterized by having the lead constituent thereof substantially uniformly distributed throughout the lining matrix in the form of extremely fine-sized particles providing improved operating characteristics to the bearing materials fabricated therefrom.
    Type: Grant
    Filed: October 14, 1987
    Date of Patent: February 27, 1990
    Assignee: Federal-Mogul Corporation
    Inventor: Michael D. Lytwynec
  • Patent number: 4887496
    Abstract: Disclosed is a method of making drills, endmills and other rotating-and-cutting tools comprising the steps of: extruding super-hard metal powder into a spiral rod; sintering the spiral rod; forming a-ferrous metal powder layer around the rear end of the spiral rod sinter; and heating and then cooling the ferrous metal powder layer in such a way that voids may be caused to appear in the ferrous metal powder layer, which is integrally connected to the spiral rod sinter to make up its shank. Thanks to the existence of the voids in the shank layer, any inner strain will be dissipated, assuring that crack-free products result.
    Type: Grant
    Filed: September 21, 1988
    Date of Patent: December 19, 1989
    Inventor: Yoshinobu Kobayashi
  • Patent number: 4885133
    Abstract: A wear-resistant sintered iron-based alloy and a process for producing the alloy are described, wherein the alloy comprises a first phase having a martensite composition which comprises from 0.5 to 3.0 wt % of Cr, from 0.4 to 1.0 wt % of Mn, from 0.1 to 0.4 wt % of Mo, and the balance of Fe, based on the total amount of said first phase; a second phase having a martensite and Cr carbide composition which comprises from 10 to 20 wt % of Cr and the balance of Fe, based on the total amount of said second phase; and from 1.0 to 2.5 wt % of C, based on the total amount of said alloy; wherein said first phase and said second phase are present as a mixture containing from 10 to 80% by volume of said second phase, based on the total volume of said alloy; and said alloy is substantially free from any residual austenite.
    Type: Grant
    Filed: April 6, 1989
    Date of Patent: December 5, 1989
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventor: Satoshi Fujii
  • Patent number: 4875946
    Abstract: A heat-treatment process for producing rare earth-cobalt permanent magnets having relatively high and reproducible magnetic properties wherein one or more controlled cooling rates are applied in temperatures ranging from a sintering temperature and the isothermal annealing temperature. The controlled cooling rates are preferably divided into two steps. In the first step, the cooling rate is preferably greater than 10.degree. C./min. In the second step, the cooling rate is preferably less than 10.degree. C./min. and is ideally in the range of 2.degree.-4.degree. C./min. By the heat-treatment process of this invention, a permanent magnet having a high intrinsic coercivity of more than 20 kOe, a maximum energy product of greater than 19 MGOe, and a coercivity of greater than 8.1 kOe can be reproducibly obtained.
    Type: Grant
    Filed: February 2, 1988
    Date of Patent: October 24, 1989
    Assignee: Industrial Technology Research Institute
    Inventors: Shiang-Jiun Heh, Swe-Kai Chen, Fu-Teh Jin, Li-Kou Chen
  • Patent number: 4859164
    Abstract: A vane used in a rotary compressor, and rotary compressor including the vane are made from a ferrous sintered alloy. The method comprises the steps of preparing metal powder mixture primarily containing iron, compacting the powder mixture to obtain a powder compact, sintering the powder compact to obtain a sintered body, subjecting sub-zero treatment to the sintered body, and tempering the sintered body. The sintered alloy product is used as a vane slidably disposed in a vane groove of the rotary compressor whose cooling medium is maintainable without deterioration of its property.
    Type: Grant
    Filed: November 25, 1987
    Date of Patent: August 22, 1989
    Assignee: Nippon Piston Ring Co., Ltd.
    Inventor: Soichi Shimomura
  • Patent number: 4838936
    Abstract: Spiral parts, such as orbiting and fixed scroll plates having involute wraps, for use in scroll compressors, the parts having low coefficient of thermal expansion and high tensile strength and Young's modulus, are formed by combining a self-lubricating power into aluminum raw material powder prior to compression and forging. As an alternative to and in conjunction with the foregoing, temperatures during preform heating and in the die for forging are controlled to be in respective ranges of 300.degree. to 500.degree. C. and 150.degree. to 500.degree. C. Aluminum alloy fine powder preferably has a particle diameter no larger than 350 .mu.m. The self-lubricating powder preferably forms 1 to 25% of the mix by volume, and contains at least one member selected from the group consisting of graphite, BN, and MoS.sub.2.
    Type: Grant
    Filed: May 23, 1988
    Date of Patent: June 13, 1989
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventor: Kiyoaki Akechi
  • Patent number: 4830821
    Abstract: A contact forming material for a vacuum valve or vacuum circuit breaker comprising (a) a conductive material consisting of copper and/or silver, and (b) an arc-proof material consisting of chromium, titanium, zirconium, or an alloy thereof wherein the amount of said arc-proof material present in said conductive material matrix is no more than 0.35% by weight. This contact forming material is produced by a process which comprises the steps of compacting arc-proof material powder into a green compact, sintering said green compact to obtain a skeleton of the arc-proof material, infiltrating the voids of said skeleton with a conductive material, and cooling the infiltrated material. The contact forming material can provide contacts for a vacuum valve or vacuum circuit breaker which has excellent characteristics such as temperature rise characteristic and contact resistance characteristic.
    Type: Grant
    Filed: July 26, 1988
    Date of Patent: May 16, 1989
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tsutomu Okutomi, Seishi Chiba, Mikio Okawa, Tadaaki Sekiguchi, Hiroshi Endo, Tsutomu Yamashita
  • Patent number: 4820141
    Abstract: A method for forming non-equilibrium and/or metastable metallic or non-metallic powder, foil or fine wire material into a solid body comprises charging the material into a metal container, subjecting the metal container containing the material to rolling at a temperature at which the inherent properties of the material are maintained, and thereafter removing the metal container.
    Type: Grant
    Filed: December 11, 1987
    Date of Patent: April 11, 1989
    Assignee: Nippon Steel Corporation
    Inventors: Hideo Shingu, Mitsunobu Abe, Takashi Sato, Toshio Yamada
  • Patent number: 4814139
    Abstract: A thermally stable permanent magnet with reduced irreversible loss of flux and improved intrinsic coercivity iHc of 15KOe or more having the following composition:(Nd.sub.1-.alpha. Dy.sub..alpha.)(Fe.sub.1-x-y-z Co.sub.x B.sub.y M.sub.z).sub.awherein M represents at least one element selected from the group consisting of Nb, Mo, Al, Si, P, Zr, Cu, V, W, Ti, Ni, Cr, Hf, Mn, Bi, Sn, Sb and Ge, 0.01.ltoreq.x.ltoreq.0.4, 0.04.ltoreq.y.ltoreq.0.20, 0.ltoreq.z.ltoreq.0.03, 4.ltoreq.a.ltoreq.7.5 and 0.03.ltoreq..alpha..ltoreq.0.40. This can be manufactured by (a) sintering an alloy having the above composition by a powder metallurgy method, (b) heating the sintered body at 750.degree.-1000.degree. C. for 0.2-5 hours, (c) slowly cooling it at a cooling rate of 0.3.degree.-5.degree. C./min to temperatures between room temperature and 600.degree. C., (d) heating it at 540.degree.-640.degree. C. for 0.2-3 hours, and (e) rapidly cooling it at a cooling rate of 20.degree.-400.degree. C./min.
    Type: Grant
    Filed: January 2, 1987
    Date of Patent: March 21, 1989
    Assignee: Hitachi Metals, Ltd.
    Inventors: Masaaki Tokunaga, Hiroshi Kogure, Noriaki Meguro, Chitoshi Hagi
  • Patent number: 4810289
    Abstract: A process of hot isostatic pressing of powders to form electrical contacts is characterized by the steps: (A) mixing powders, 1 in the Drawing, from metal containing powder or metal containing powder plus carbon powder, where at least one of Ag and Cu is present, (B) thermal cleaning treatment of the powder, 2 in the Drawing, (C) granulating the thermally treated powder, 3 in the Drawing, (D) uniaxially pressing the powders without heating, 5 in the Drawing, to provide a compact, (E) placing at least one compact in a pressure-transmitting, pressure-deformable container, 6 in the Drawing, and surrounding each compact with fine particles of a separating material, (F) evacuating air from the container, 7 in the Drawing, (G) sealing the compacts inside the container, 8 in the Drawing, (H) hot isostatic pressing, 9 in the Drawing, the compacts through the pressure transmitting material at a pressure from 352 kg/cm.sup.2 to 2,115 kg/cm.sup.2 and a temperature from 0.5.degree. C. to 100.degree. C.
    Type: Grant
    Filed: April 4, 1988
    Date of Patent: March 7, 1989
    Assignee: Westinghouse Electric Corp.
    Inventors: Norman S. Hoyer, Natraj C. Iyer
  • Patent number: 4714587
    Abstract: A process for producing titanium alloy articles by Hot Isostatic Pressing of a rapidly-solidified titanium alloy powder is provided wherein such pressing is carried out at a pressure greater than 30 ksi, and a temperature of about 60 to 80 percent of the beta-transus temperature of the alloy, in degrees C. Hot Isostatic Pressing under these conditions allows retention of the fine microstructure of the rapidly-solidified powder. The compacted article may be subjected to heat treatment to alter its microstructure.
    Type: Grant
    Filed: February 11, 1987
    Date of Patent: December 22, 1987
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Daniel Eylon, Francis H. Froes
  • Patent number: 4702885
    Abstract: A process for producing an aluminum alloy comprises: producing an aluminum alloy powder, consisting of (A) 10 to 36 wt % of Si, 1 to 12 wt % of Fe, 2 to 10 wt % of at least one of metal selected from the group consisting of Ni, Co, Cr and Mn, reminder of the alloy powder consisting of aluminum, or consisting of (B) 10 to 36 wt % of Si, 2 to 10 wt % of Ni, 2 to 10 wt % of at least one of metal selected from the group consisting of Fe, Co, Cr, and Mn, and remainder of the alloy powder consisting of aluminum; compressing a mass of the powder by either compacting the power or accumulating the powder in a can where in case of compacting the powders are so as to have its actual density ratio of 65% to 90%, and in case of the accumulation the powders are compressed so as to have its actual density ratio of not more than 90%; heating the thus compressed mass of powder in convection type heating furnace at a temperature of 250.degree. C. to 550.degree. C.
    Type: Grant
    Filed: June 27, 1986
    Date of Patent: October 27, 1987
    Assignee: Sumitomo Electric Industries, LTD.
    Inventors: Yusuke Odani, Kiyoaki Akechi, Nobuhito Kuroishi
  • Patent number: 4676830
    Abstract: A superior high-temperature strength aluminum alloy material is produced by consolidating rapdily solidified particulates of an aluminum alloy into a desired configuration, the aluminum alloy consisting of, in weight percentages, 4 to 15% Fe, and 0.5 to 8% V and the balance being essentially aluminum. The aluminum alloy may further contain at least one element selected from the group consisting of 0.5 to 8% Mo, 0.5 to 8% Ni, 0.3 to 8% Zr and 0.5 to 8% Ti and these additional components develop a further increased strength in the resulting formed materials. Since the consolidated aluminum materials above specified have a superior strength at high temperatures as well as moderate temperature without an expensive Ce, they are highly useful as economical heat-resistant materials for various applications, particularly for the fields where high strength at high temperatures and lightness of weight are required.
    Type: Grant
    Filed: August 7, 1985
    Date of Patent: June 30, 1987
    Assignee: Sumitomo Light Metal Industries, Ltd.
    Inventors: Susumu Inumaru, Shigenori Yamauchi, Kazuhisa Shibue, Hideo Sano, Kiyofumi Ito
  • Patent number: 4670215
    Abstract: There is disclosed a process for forming a wear-resistant, sintered layer on a metallic substrate. The process comprises steps of adhesively attaching to a surface of metallic substrate an alloy particle sheet containing 94 to 99 weight % of ternary eutectic alloy particles and 6 to 1 weight % of acryl binder, heating in a non-oxidating atmosphere to a temperature of 150.degree. to 380.degree. C. and holding at the temperature for at least 5 minutes, and heating a sintering temperature of the alloy particles.
    Type: Grant
    Filed: February 19, 1985
    Date of Patent: June 2, 1987
    Inventors: Tsuyoshi Morishita, Sigemi Osaki, Noriyuki Sakai, Yukio Shimizu, Toshiharu Konishi, Takahumi Sakuramoto
  • Patent number: 4661155
    Abstract: A molded, boron carbide-containing, sintered article which includes at least 65 percent by volume boron carbide; and from 5 to 35 percent by volume of at least one binder metal selected from the group consisting of molybdenum, molybdenum alloys, tungsten and tungsten alloys, having a melting point above 1,800.degree. C., and forming no molten borides or carbides within a temperature range of from 1,800.degree. to 1,950.degree. C. A method for producing the article includes the steps of mixing to obtain a homogeneous mixture from 20 to 80 percent by weight boron carbide particles having a particle size ranging from 1 to 1,650 microns with up to 80 percent by weight of particles of the at least one binder metal having a particle size ranging from 35 to 100 microns; introducing the homogeneous mixture into a graphite matrix mold; heating to sinter the homogeneous mixture at a temperature ranging from 1,800.degree. to 2,000.degree. C.
    Type: Grant
    Filed: May 21, 1986
    Date of Patent: April 28, 1987
    Assignee: Kernforschungszentrum Karlsruhe GmbH
    Inventors: Volker Heinzel, Hossein-Ali Keschtkar, Ingeborg Schub
  • Patent number: 4657822
    Abstract: Alloy powder is packed into a mold which comprises a complex-shaped solid aphite inner core and a similarly complex-shaped thin glass outer wall. The mold is evacuated, sealed, and then heated to the alloy sintering temperature, the glass softens and applies an isostatic pressure on the alloy as the alloy particles consolidate. After the consolidation step, the mold and its contents are cooled and the glass and graphite materials are removed from the alloy object. This method is particularly useful for preparing complex fittings of Nitinol shape memory alloys.
    Type: Grant
    Filed: July 2, 1986
    Date of Patent: April 14, 1987
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: David Goldstein
  • Patent number: 4655853
    Abstract: The invention involves a method for making powder metal forging preforms of high strength ferrous-base alloys in which the times and temperatures for reducing oxides, sintering, and carburizing are substantially reduced as compared to conventional techniques. The method includes simultaneously sintering and carburizing the preforms in the hot zone of a sintering furnace at temperatures below 2000.degree. F. and for a period of time above austenitic temperature not exceeding about 35 minutes. After carburizing the preforms are rapidly cooled to freeze the case carbon gradient obtained in the hot zone.
    Type: Grant
    Filed: April 18, 1985
    Date of Patent: April 7, 1987
    Assignee: Federal-Mogul Corporation
    Inventors: Larry E. Byrnes, Jon T. Gabrielsen
  • Patent number: 4650519
    Abstract: A metal body having high tensile strength and ductility at temperatures over 1000.degree. F. is provided. The body is prepared by hot isostatic pressing of powder formed by atomization of a melt of an alloy. The alloy composition is according to the formula(Ni.sub.1-x-z Co.sub.x Al.sub.z).sub.100-y B.sub.ywherein x is at least 0.05, andwherein y is 0.10 to 2.0, andwherein z is 0.23 to 0.25.The consolidated body is suitable for machining to final dimensions. To relieve stresses developed from the machining the body may be annealed for a couple of hours at temperatures between 800.degree. C. and 1200.degree. C.
    Type: Grant
    Filed: October 3, 1985
    Date of Patent: March 17, 1987
    Assignee: General Electric Company
    Inventors: Keh-Minn Chang, Shyh-Chin Huang, Alan I. Taub
  • Patent number: 4629505
    Abstract: A metallurgical method including cooling molten aluminum particles and consolidating resulting solidified particles into a multiparticle body, wherein the improvement comprises the provision of greater than 0.15% of a metal which diffuses in the aluminum solid state at a rate less than that of Mn.Aluminum containing greater than 0.15% of a metal which diffuses in the aluminum solid state at a rate less than that of Mn.
    Type: Grant
    Filed: April 2, 1985
    Date of Patent: December 16, 1986
    Assignee: Aluminum Company of America
    Inventor: Henry G. Paris
  • Patent number: 4615734
    Abstract: A solid particle erosion resistant coating includes angular titanium carbide particles uniformly dispersed through a high chromium iron matrix. In one form, the aggregate comprises, by weight, about 30-50% TiC, about 10-30% Cr, about 1.5-5% C and the balance essentially iron in the form of ferrite. The matrix also includes metallurgically identifiable amounts of high chromium content M.sub.7 C.sub.3 carbides therethrough. The coating does not exhibit austenitic or martensitic structure therehthough. A powder alloy consolidated body also includes a surface adjacent region having a similar TiC and high chromium iron matrix. Further, a method for obtaining the coating includes heating above the austenitization temperature of the matrix alloy and below the melting temperature of iron, and cooling the aggregate so as to attain iron in the form of ferrite in the matrix.
    Type: Grant
    Filed: February 7, 1985
    Date of Patent: October 7, 1986
    Assignee: General Electric Company
    Inventor: Donald R. Spriggs
  • Patent number: 4614544
    Abstract: A high strength powder metal part formed from an alloy of iron, nickel, molybdenum and carbon and having an ultimate tensile strength of at least 175,000 pounds per square inch. The powder metal part is made by mixing the alloy with a lubricant, forming the mixture into the desired part shape, sintering in a dissociated ammonia atmosphere, and cryogenically cooling the sintered part.
    Type: Grant
    Filed: October 22, 1985
    Date of Patent: September 30, 1986
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: Chaman Lall
  • Patent number: 4608317
    Abstract: A method for manufacturing a metal sintered body disclosed herein is characterized by the use of steps of: mixing 70 to 90 weight % of self-fluxing alloy powder and 10 to 30 weight % of metal powder of high melting point having a higher melting point than that of the self-soluble metal powder and in which the self-fluxing alloy powder is liable to be deposited thereon to obtain a metal powder having a sintering property; using a material in which 1 to 10 weight % of plastic binder is kneaded with the metal powder having a sintering property to obtain a molded body having a predetermined shape; and sintering the molded body at a temperature in excess of a liquid phase line of the self-fluxing alloy powder.
    Type: Grant
    Filed: April 15, 1985
    Date of Patent: August 26, 1986
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Osamu Kobayashi, Hiroshi Sasaki, Toshiki Kaneko, Hideaki Ikeda, Yoshihisa Yamamura
  • Patent number: 4602957
    Abstract: A magnetic powder core, suitable for use in a low frequency power device, is prepared by a method including the steps of coating an atomized iron powder from an aqueous solution of potassium dichromate, drying the powder, compressing the powder to form a compact and heat treating the compact until it becomes partially sintered. Cores having coercivities below 240.sup.A /m, saturation inductions exceeding 1.3 Tesla and resistivities exceeding 500 microhm cm are disclosed.
    Type: Grant
    Filed: September 6, 1985
    Date of Patent: July 29, 1986
    Assignee: EMI Limited
    Inventors: Harriet C. Pollock, Andrew L. Smith
  • Patent number: 4601876
    Abstract: A sintered Fe-Cr-Co type magnetic alloy consisting essentially of 20-35% Cr, 3-15% Co and the balance substantially of Fe and a method of producing an article made of the alloy are disclosed. The method comprises the steps of blending at least one of an Fe-Cr powder and Fe-Cr-Co powder with a carbonyl Fe-powder and a Co-powder, if necessary to make up to said alloy composition, to provide a powder blend, the average particle size of said Fe-Cr powder and Fe-Cr-Co powder being 200 mesh or smaller in size, and the surface of these powders having been activated; compacting the resulting powder blend to provide a compact; sintering the resulting compact in an atmosphere in which the total amount of oxygen and nitrogen has been restricted to not more than 3 ppm; and effecting the heat treatment and magnetization of the resulting sintered alloy.
    Type: Grant
    Filed: August 13, 1984
    Date of Patent: July 22, 1986
    Assignee: Sumitomo Special Metals Co., Ltd.
    Inventors: Michio Yamashita, Setsuo Fujimura
  • Patent number: 4564501
    Abstract: In the consolidation by atmospheric pressure of nickel-titanium alloy powders, the improvement comprising slowly cooling down the consolidated alloy objects under a high pressure.
    Type: Grant
    Filed: July 5, 1984
    Date of Patent: January 14, 1986
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: David Goldstein
  • Patent number: 4534935
    Abstract: Sponge titanium powder is compacted, advantageously by roll compaction to a density in the range of about 60% to 80% of the density of solid titanium metal, thereafter heat treated in vacuum at about 500.degree. C. to 750.degree. C., cooled in vacuum to 300.degree. C. and quenched to 100.degree. C. to provide a substrate for electrodes useful in electrolytic processes.
    Type: Grant
    Filed: January 9, 1984
    Date of Patent: August 13, 1985
    Assignee: INCO Limited
    Inventors: John Ambrose, Douglas K. Charles, Bruce R. Conard, Carlos Diaz, Charles E. O'Neill, Wayne P. Leavoy
  • Patent number: 4455353
    Abstract: Article produced in a mould for a plastics moulding tool having a mould surface defining the contours of the article, with the article comprising a body formed from a composition comprising a sinterable material having a sintering temperature which material, before sintering, is shapable into a desired shape and which during sintering forms a porous body having pores, the sinterable material being at least partially sintered in the mould, and also comprising a matrix having a lower melting point than the sintering temperature of the sinterable material, with the matrix comprising a matrix metal which is infiltrated in the porous body to substantially fill the pores.
    Type: Grant
    Filed: September 28, 1981
    Date of Patent: June 19, 1984
    Assignee: Uddeholms Aktiebolag
    Inventor: Lars M. Bruce