Additional Operation Between Heating Steps Patents (Class 419/55)
  • Patent number: 4840767
    Abstract: A cathode is made from a mixture of tungsten and iridium powders using a ium iridiate formed from barium peroxide and iridium oxide as the impregnant.
    Type: Grant
    Filed: October 3, 1988
    Date of Patent: June 20, 1989
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Louis E. Branovich, Gerard L. Freeman, Bernard Smith, Donald W. Eckart
  • Patent number: 4836978
    Abstract: A production method of a vacuum circuit breaker electrode comprises the steps of mixing conductive metal powder, and refractory material powder with a higher melting point than said conductive metal powder, compacting the resultant mixture to form a compact, presintering the compact in a atmosphere of high purity hydrogen, sealing a presintered body in a capsule while exhausting, heating and degassing, and subjecting the sealed capsule to hot isostatic pressing treatment. The conductive metal powder is one or both of Cu and Ag. The hot isostatic pressing treatment is effected at a temperature higher than a melting point of the conductive metal so that the presintered body is sintered under liquid phase, and a part of molten conductive metal component is seeped out on a sintered body surface.
    Type: Grant
    Filed: September 2, 1987
    Date of Patent: June 6, 1989
    Assignee: Hitachi, Ltd.
    Inventors: Ryuji Watanabe, Hisashi Andoh, Kiyoji Iwashita, Kinko Shimizu
  • Patent number: 4832893
    Abstract: A method for producing PLZT generally expressed as (Pb.sub.1-x La.sub.x) (Zr.sub.1-y Ti.sub.y).sub.1-x/4 O.sub.3 (0<x.ltoreq.0.3, 0.ltoreq.y.ltoreq.1.0) comprises the steps of forming a coprecipitated body by reacting solution containing at least one of Pb, La and Ti with a zirconium-containing solution and a precipitation-forming solution, or (a) forming a solution containing at least one of Pb, La and Ti forming PLZT generally expressed as (Pb.sub.1-x La.sub.x) (Zr.sub.1-y Ti.sub.y).sub.1-x/4 O.sub.3 (0<x.ltoreq.0.3, 0.ltoreq.y.ltoreq.1.0) and a zirconium-containing solution and carrying out a hydrolysis reaction to produce a sol body, (b) drying and then presintering the coprecipitated body at a temperature of from 700.degree. to 1300.degree. C. to form a modified zirconia powder, (c) mixing the presintered body with a compound having a remaining component composition of a required PLZT composition, (d) presintering the mixture at a temperature of from 500.degree. to 1000.degree. C.
    Type: Grant
    Filed: December 16, 1987
    Date of Patent: May 23, 1989
    Assignees: Nippondenso Co., Ltd., Science and Technology Agency National Institute
    Inventors: Michio Hisanaga, Kazunori Suzuki, Masataka Naito, Shinichi Shirasaki
  • Patent number: 4826546
    Abstract: A process for producing permanent magnet materials, which comprises the steps of:forming an alloy powder having a mean particle size of 0.3-80 microns and composed of, in atomic percentage, 8-30% R (provided that R is at least one of rare earth elements including Y), 2-28% B, and the balance being Fe and inevitable impurities,sintering the formed body at a temperature of 900.degree.-1200.degree. C.,subjecting the sintered body to a primary heat treatment at a temperature of 750.degree.-1000.degree. C.,then cooling the resultant body to a temperature of no higher than 680.degree. C. at a cooling rate of 3.degree.-2000.degree. C./min, andfurther subjecting the thus cooled body to a secondary heat treatment at a temperature of 480.degree.-700.degree. C.35 MGOe, 40 MGOe or higher energy product can be obtained with specific compositions.
    Type: Grant
    Filed: August 13, 1987
    Date of Patent: May 2, 1989
    Assignee: Sumitomo Special Metal Co., Ltd.
    Inventors: Hitoshi Yamamoto, Masato Sagawa, Setsuo Fujimura, Yutaka Matsuura
  • Patent number: 4818480
    Abstract: A cathode is made from a mixture of tungsten and iridium powders using a ium peroxide containing material as the impregnant.
    Type: Grant
    Filed: June 9, 1988
    Date of Patent: April 4, 1989
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Louis E. Branovich, Gerard L. Freeman, Bernard Smith, Donald W. Eckart
  • Patent number: 4818628
    Abstract: A process for making a composite bearing material comprising a steel backed, prealloyed, lead-bronze sintered powder metal matrix whereby the first sinter step includes induction heating the prealloyed powder and steel backing to above 650.degree. C. and thereafter sintering the same at temperatures of about 850.degree. C. in a second sintering furnace. A composite bearing material made by the same process and comprising a lead particle size averaging less than about 8 microns and having no lead islands larger than about 44 microns.
    Type: Grant
    Filed: August 31, 1987
    Date of Patent: April 4, 1989
    Assignee: Federal-Mogul Corporation
    Inventors: Robert G. Alexander, George C. Pratt
  • Patent number: 4817858
    Abstract: Method of manufacturing a workpiece of any given cross-sectional dimensions from an oxide-dispersion-hardened nickel-based superalloy available in the form of coarse-grained longitudinally directed columnar crystals by connecting previously very finely machined workpiece parts derived from a semi-finished product by diffusion-bonding using hot isostatic pressing, the workpiece parts being first heat-treated under a protective gas in the temperature range of 50.degree. to 100.degree. C. below the recrystallization temperature, under a pressure p.sub.k of not more than 5 MPa with the machined surfaces to be connected joined together, the workpiece then being heated at least to a critical temperature T.sub.K, above which no further cold working takes place, and the pressure then being gradually increased to the diffusion bonding pressure p.sub.max of 100 to 300 MPa with simultaneous increase in temperature are a heating rate of not more of 2.degree. C./min to the diffusion bonding temperature T.sub.D of 0 to 50.
    Type: Grant
    Filed: May 11, 1988
    Date of Patent: April 4, 1989
    Assignee: BBC Brown Boveri AG
    Inventor: Clemens Verpoort
  • 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: 4810462
    Abstract: The method for fabricating a metal body having a flaw of predetermined size and shape located therein comprises placing half of the metal powder required to make the metal body in the die of a press and pressing it to create a flat upper surface thereon. A piece of copper foil is cut to the size and shape of the desired interior crack and placed on the upper surface of the powder and centered in position. The remaining powder is then placed in the die to cover the copper foil. The powder is first cold pressed and removed from the press. The powder metal piece is then sintered in a furnace at a temperature above the melting point of the copper and below the melting point of the metal. It is then removed from the furnace, cooled to room temperature, and placed back in the die and pressed further. This procedure results in an interior flaw or crack.
    Type: Grant
    Filed: February 17, 1988
    Date of Patent: March 7, 1989
    Assignee: Iowa State University Research Foundation, Inc.
    Inventors: David K. Hsu, Donald O. Thompson
  • Patent number: 4784690
    Abstract: A low density tungsten alloy article is disclosed and the method for producing the article. The method involves compacting a relatively uniform tungsten alloy powder with the tungsten content comprising no greater than about 90% by weight of the alloy and the balance a matrix phase to produce a preformed article which is then sintered in a reducing atmosphere at a temperature below the melting point of the matrix phase for a sufficient time to form a densified article which is mechanically worked to produce the final article.
    Type: Grant
    Filed: October 11, 1985
    Date of Patent: November 15, 1988
    Assignee: GTE Products Corporation
    Inventor: James A. Mullendore
  • Patent number: 4762559
    Abstract: A tungsten-nickel-iron-cobalt high density alloy having unexpected improved strength and hardness properties and the method of making such alloy are disclosed. The alloy has from about 85-98% by weight tungsten with the remainder being a nickel-iron-cobalt binder in which the cobalt is present in amounts of from at least about 5% up to 47.5% by weight of the binder and the amount of cobalt being equal to or less than the amount of nickel. After the powders of the elements in the indicated amounts are homogeneously blended, compacted into a shape and sintered, the sintered shape is subjected to a heat treatment in a flowing argon atmosphere for a period of time and at a temperature at least sufficiently high to solubilize the intermetallic or .mu. phase, Co.sub.7 W.sub.
    Type: Grant
    Filed: July 30, 1987
    Date of Patent: August 9, 1988
    Assignee: Teledyne Industries, Incorporated
    Inventors: Thomas W. Penrice, James Bost
  • Patent number: 4732622
    Abstract: A method of producing products from a mechanically alloyed, dispersion strengthened iron-base powder comprises consolidating the powder and working the consolidated body to the desired product shape. To obtain a desired grain size in the product, the process includes at least two stages of recrystallization annealing which may be effected after consolidation or alternatively at least one of the recrystallization anneals may be carried out while the material is still in powder form.
    Type: Grant
    Filed: September 23, 1986
    Date of Patent: March 22, 1988
    Assignee: United Kingdom Atomic Energy Authority
    Inventor: Andrew R. Jones
  • 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: 4699763
    Abstract: An electrical contact material characterized by a pressed and sintered powder of silver composite with about 5 weight percent of graphite fibers.
    Type: Grant
    Filed: June 25, 1986
    Date of Patent: October 13, 1987
    Assignee: Westinghouse Electric Corp.
    Inventors: Semahat D. Sinharoy, Jere L. McKee, Norman S. Hoyer
  • Patent number: 4693747
    Abstract: Disclosed is a metal alloy product having increased resistance to fatigue crack growth and having coarse grains distributed in a fine grain structure, the coarse grains having a different alloy composition from the fine grain structure.
    Type: Grant
    Filed: November 18, 1985
    Date of Patent: September 15, 1987
    Assignee: Aluminum Company of America
    Inventors: Philip E. Bretz, Jocelyn I. Petit, Ralph R. Sawtell, Asuri K. Vasudevan
  • Patent number: 4690797
    Abstract: A method for the manufacture of large area silicon crystal bodies suitable for use in the manufacture of solar cells wherein silicon powder having a small grain size is used as the starting material. This powder is compressed to form a thin layer in a suitable form, the form having at least a surface composed of silicon or a silicon compound. The form is filled to a depth approximating the final dimensions of the article. The powder is sintered in the form, and the compressed, sintered layer is converted into a self-supporting silicon foil. This foil is melted partially up to at least half its thickness and recrystallized in a two-stage temperature treatment. The melting occurs by means of a single-sided energy irradiation. The silicon foil is not deteriorated in terms of its mechanical stability and shaped by means of the single-sided, optical type heating.
    Type: Grant
    Filed: September 17, 1986
    Date of Patent: September 1, 1987
    Assignee: Siemens Aktiengesellschaft
    Inventors: Achim Eyer, Armin Raeuber, Norbert Schillinger
  • Patent number: 4689077
    Abstract: A method is disclosed for manufacturing a reaction sintered composite article which comprises at least one ceramic component. The method comprises preparing a particulate mixture of precursor powders leading to the formation of said composite material upon reaction sintering, pressing said particulate mixture to a self-sustaining body, heating said body up to a temperature below the temperature at which the reaction sintering is initiated, comminuting the heat treating body, selecting particles of a suitable grain size distribution, pressing said particles into shapes of desired size and configuration, and heating said shapes up to a temperature at which the reaction sintering is initiated. The reaction sintered body comprises borides, carbides, nitrides or silicides of a transition metal of the groups IVb, Vb or VIb of the periodic table (comprising titanium, hafnium, zirconium, vanadium, niobium, tantalum, chromium, molybdenum and tungsten), and a metal oxide.
    Type: Grant
    Filed: May 19, 1986
    Date of Patent: August 25, 1987
    Assignee: ELTECH Systems Corporation
    Inventors: Michel Chevigne, Dominique Darracq, Jean-Pol Wiaux
  • Patent number: 4680161
    Abstract: A method of producing a sliding composite material. The method comprises the step of: forming an adhesive layer bonded to the surface of a metal strip by sintering a powder for the adhesive layer which contains no solid lubricant and which is disposed onto the surface of the metal strip; forming a surface layer by sintering another powder for the surface layer which contains a solid lubricant and which is disposed onto the sintered adhesive layer; and rolling the resulting layers and the metal strip to obtain the composite material.
    Type: Grant
    Filed: August 13, 1986
    Date of Patent: July 14, 1987
    Assignee: Daido Metal Company Ltd.
    Inventor: Takashi Muto
  • Patent number: 4680162
    Abstract: Ag-SnO system alloy electrical contact materials. The Ag alloy before internal oxidation thereof contains Sn of an amount of 5-20 weight %, 0.5-15 weight % of which amount is in the powder form of SnO.sub.2. The existence of SnO.sub.2 particles in the alloy accelerates the internal oxidation speed, allowing oxygen to readily pass aside and between the particles, while the internal oxidation per se makes the alloy more dense by eliminating spaces between SnO.sub.2 grain particles on account of the volumeric expansion of Sn which results from the internal oxidation thereof.
    Type: Grant
    Filed: February 28, 1986
    Date of Patent: July 14, 1987
    Assignee: Chugai Denki Kogyo K.K.
    Inventor: Akira Shibata
  • Patent number: 4666787
    Abstract: A material which is intended for use in sliding surface bearings comprises a metallic backing, a porous metallic substrate layer applied to said backing, and a PTFE-filler mixture, which completely fills the pores of the substrate layer and constitutes an antifriction layer. The bond strength between the antifriction layer and the substrate layer is improved by coating that surface of the substrate layer which faces the antifriction layer with a primer.
    Type: Grant
    Filed: February 14, 1986
    Date of Patent: May 19, 1987
    Assignee: Kolbenschmidt Aktiengesellschaft
    Inventors: Wolfgang Bickle, Jurgen Braus, Hans-Paul Baureis
  • Patent number: 4654195
    Abstract: A method for fabricating ribbed electrodes that accommodates the shrinkage which occurs during thermal cycling reducing the cracks caused by the confining stresses of a mold. A composition comprising a metal selected from the group consisting of nickel, copper and mixtures thereof with chromium onto a ribbed mold. The mold and composition are prefired in a reducing atmosphere forming a ribbed electrode. The ribbed electrode is removed from the mold and sintered in a reducing atmosphere.
    Type: Grant
    Filed: December 23, 1985
    Date of Patent: March 31, 1987
    Assignee: International Fuel Cells Corporation
    Inventors: Wayne G. Wnuck, Bryan J. Dec, Raymond J. Jarvis
  • Patent number: 4634572
    Abstract: A system for automatically consolidating a plurality of metallic or ceramic (or mixtures thereof) powder preforms is disclosed. The system comprises an assembly container wherein a consolidation container is filled with hot consolidation particles for facilitating the consolidation, and a hot preform to be consolidated thereby. The atmosphere of the assembly container is maintained hot and inert or reducing during assembly of the consolidation charge. Further disclosed are means for automatically delivering the consolidation containers, consolidation particles and preforms to the assembly container. The system includes means for conveying the consolidation containers to a press for consolidation, for separating the containers from the consolidation particles and consolidated preform after pressing, and for recycling the consolidation particles and consolidation containers.
    Type: Grant
    Filed: October 25, 1984
    Date of Patent: January 6, 1987
    Assignee: Metal Alloys, Inc.
    Inventor: Robert D. Lichti
  • Patent number: 4615735
    Abstract: Powder metallurgy products of high tensile strength are formed in a pore-free state by a novel process which entirely avoids the use of canisters. An open-pore specimen is purged with depurative gas, backfilled with a reactive gas and, while still immersed in the reactive gas, compressed isostatically to an extent necessary to close the pores. The specimen may then be compressed to full density without the need for either high vacuum or a depurative or reactive gas atmosphere.
    Type: Grant
    Filed: September 18, 1984
    Date of Patent: October 7, 1986
    Assignee: Kaiser Aluminum & Chemical Corporation
    Inventor: Steven W. Ping
  • Patent number: 4609527
    Abstract: The specification discloses a powder process in which metal or ceramic particles are mixed with a binder such as ultra high molecular weight polyethylene powder and are compacted. The compacted shape is heated to a temperature near the melting point of the binder to consolidate the binder and produce a green shape. The green shape is formed and the binder is removed. Thereafter, the shape is sintered to form a final part.
    Type: Grant
    Filed: May 24, 1985
    Date of Patent: September 2, 1986
    Inventors: James R. Rinderle, Michael K. Pratt
  • Patent number: 4606884
    Abstract: The present invention concerns the manufacture of bars, wires or profiled elements by hot transformation which may be followed by cold transformation. The invention particularly concerns a new process for the manufacture of a composite billet for hot transformation as well as a method for the manufacture of products which are difficult to transform by making use of such a composite billet.
    Type: Grant
    Filed: July 3, 1984
    Date of Patent: August 19, 1986
    Assignees: Microfusion, Commissariat a l'Energie Atomique
    Inventors: Jean Gavinet, Bruno Childeric
  • Patent number: 4605599
    Abstract: A method of producing a high density tungsten alloy sheet product is disclosed which utilizes as a starting material a thin-gage sheet or foil substrate of a first alloy constituent, such as pure iron or an alloy thereof. A prescribed mixture of tungsten metal powder and a second metal alloy constitutent powder, such as nickel, is loaded on the substrate and partially consolidated in a protective atmosphere furnace to form a porous tungsten alloy skeleton which is also partially bonded to the substrate. The product is then preferably cooled in a protective atmosphere and sheared into desired lengths. The sized pieces are then further heated in a protective atmosphere at gradually increasing temperatures to a point above the melting point of the substrate, whereupon the substrate sheet or foil melts and infiltrates the porous tungsten alloy skeleton to complete the densification of the product.
    Type: Grant
    Filed: December 6, 1985
    Date of Patent: August 12, 1986
    Assignee: Teledyne Industries, Incorporated
    Inventors: Thomas W. Penrice, James Bost
  • Patent number: 4604260
    Abstract: A solid electrolytic capacitor is made with an Aluminum-titanium body. Aluminum and titanium powders are press-molded into a body which is then heated sufficiently to provide a porous Al-Ti alloy with an oxide layer. Next, the body is heated in an atmosphere containing at least 0.1% by volume of oxygen at a temperature in the range of about 500.degree.-700.degree. C. Thereafter, a layer of manganese dioxide is formed over the oxide layer and a cathode electrode layer is then formed over the manganese dioxide layer.
    Type: Grant
    Filed: May 22, 1985
    Date of Patent: August 5, 1986
    Assignee: NEC Corporation
    Inventors: Shigeaki Shimizu, Yoshio Arai
  • Patent number: 4602954
    Abstract: A method of producing metallic strip containing discrete particles of one or more additional metallic or non-metallic materials dispersed therein, includes the step of forming a homogeneous mix of ductile metallic particles and a minor proportion of metallic and/or non-metallic particles having chemical and/or physical properties different from those of the ductile metallic particles. A slurry coating comprising a suspension of the mixed particles in a film forming cellulose derivative is deposited onto a moving support surface, dried and removed from the support surface before being subjected to rolling to effect compaction of the ductile content of the strip and sintering at a temperature at which the metallic particles coalesce to form a matrix containing particles of the additional metallic or non-metallic material(s) which either remain as discrete particles or alloy with the matrix.
    Type: Grant
    Filed: April 4, 1985
    Date of Patent: July 29, 1986
    Assignee: Mixalloy Limited
    Inventors: Idwal Davies, John Bellis
  • Patent number: 4595556
    Abstract: A composite camshaft having a plurality of ferrous fitting members, such as cam lobes and journals, firmly bonded to a steel shaft by sintering in the presence of a liquid phase. The fitting members are fabricated as a green compact from metal powders and pre-sintered to axially shrink the compact by one-half a preselected allowance of shrinkage. Thereafter the pre-sintered fitting members are fitted on the shaft and sintered to axially shrink the compact by the remaining allowance of shrinkage and metallurgically join the shaft.
    Type: Grant
    Filed: January 2, 1985
    Date of Patent: June 17, 1986
    Assignee: Nippon Piston Ring Co., Ltd.
    Inventors: Genkichi Umeha, Shigeru Urano, Osamu Hirakawa, Shunsuke Takeguchi
  • Patent number: 4594217
    Abstract: A process for making a strip or sheet comprising dispersion strengthened metal or dispersion strengthened metal alloy which comprises rolling directly from dispersion strengthened metal powder to a green strip or sheet density of from at least 90% to 95% of theoretical density, sintering the green strip or sheet in an inert atmosphere at a temperature and for a period of time sufficient to form a rigid body; reducing the thickness of the strip or sheet by at least 25% by cold rolling or hot rolling and resintering at sintering temperature of at least about 1800.degree. F. for 40 to 75 or more minutes.
    Type: Grant
    Filed: March 7, 1985
    Date of Patent: June 10, 1986
    Assignee: SCM Corporation
    Inventor: Prasanna K. Samal
  • Patent number: 4594220
    Abstract: A method of manufacturing a scandate dispenser cathode having a matrix at least the top layer of which at the surface consists substantially of tungsten (W) and scandium oxide (Sc.sub.2 O.sub.3) and with emitter material in or below said matrix. If said method comprises the following steps:(a) compressing a porous plug of tungsten powder(b) heating said plug in a non-reactive atmosphere and in contact with scandium to above the melting temperature of scandium,(c) cooling the plug in a hydrogen (H.sub.2) atmosphere(d) pulverizing the plug to fragments(e) heating said fragments to approximately 800.degree. C. and firing them at this temperature for a few to a few tens of minutes in a hydrogen atmosphere and slowly cooling in said hydrogen atmosphere(f) grinding the fragments to scandium hydride-tungsten powder (ScH.sub.2 /W)(g) compressing a matrix or a top layer on a matrix of pure tungsten from said ScH.sub.
    Type: Grant
    Filed: December 24, 1984
    Date of Patent: June 10, 1986
    Assignee: U.S. Philips Corporation
    Inventors: Jan Hasker, Pieter Hokkeling, Johannes van Esdonk, Josef J. van Lith
  • Patent number: 4592780
    Abstract: A process for producing a flat product such as a coin includes the steps of forming a slurry comprising a suspension of particulate material in a film-forming cellulose derivative, depositing a quantity of this slurry onto a support surface, drying the slurry to form a self-supporting flat product, and removing the dried product from the support surface. The particulate material essentially comprises metallic particles and matter whose chemical composition and physical properties differ from those of the metallic particles such that the added matter is not or only partially taken into solution with the metallic particles on heat treatment of the product whereby the presence of the added matter can readily be detected following such heat treatment.
    Type: Grant
    Filed: April 4, 1985
    Date of Patent: June 3, 1986
    Assignee: Mixalloy Limited
    Inventors: Idwal Davies, John L. Fage
  • Patent number: 4591480
    Abstract: A method for sealing porous metals, which comprises applying powder of a eutectic alloy containing an element having a good diffusibility in a porous metal or powder of a mixture of metals capable of forming the eutectic alloy, to the surface of a porous metal member and heating the surface applied with the powder at a temperature higher than the eutectic temperature of the eutectic alloy to thereby cause the molten eutectic alloy to intrude into pores from the surface of the porous metal member, whereby the melting point of the molten alloy in the pores is promptly increased by diffusion of the element in the porous metal member to solidify the molten metal in the pores, sealing only pores present in the vicinity of the surface of the porous metal member.
    Type: Grant
    Filed: February 19, 1985
    Date of Patent: May 27, 1986
    Assignee: Mazda Motor Corporation
    Inventors: Tsuyoshi Morishita, Sigemi Osaki, Noriyuki Sakai, Yasuhumi Kawado
  • Patent number: 4588441
    Abstract: A process for the preparation of an iron base sintered alloy well suited for use in valve mechanism members or parts of internal combustion engines, which has a porosity of 5 to 15% and throughout the iron matrix of which is dispersed an Fe-Mo intermetallic compound in the form of a phase harder than the said matrix, by using a powder mixture obtained by incorporating into finely divided iron powders having a particle size of not more than 30 microns the given amounts of copper powders, phosphorus-containing alloy powders, carbon powders and Fe-Mo alloy powders, or the given amounts of bronze powders and/or a mixture of copper powders and tin powders, phosphorus-containing alloy powders, carbon powders and Fe-Mo alloy powders.
    Type: Grant
    Filed: January 31, 1984
    Date of Patent: May 13, 1986
    Inventors: Yutaka Ikenoue, Hiroyuki Endoh, Tadao Hayasaka
  • Patent number: 4587096
    Abstract: A canless method for hot working a nickel-base gas atomized alloy powder. The powder is blended with nickel powder, consolidated and sintered to a sufficient green strength. The surface of the resultant form is sealed to create an oxygen impervious layer so as to prevent oxidation therein. The sealed surface, in a sense, acts as a can. The form is then reheated and hot worked.
    Type: Grant
    Filed: May 23, 1985
    Date of Patent: May 6, 1986
    Assignee: Inco Alloys International, Inc.
    Inventors: William L. Mankins, Lindy J. Curtis, Gene A. Stewart
  • Patent number: 4585619
    Abstract: The invention relates to a powder metallurgical method for producing high speed steel products, the shape of which is close to the desired final shape of the product, i.e. according to the so called near net shape technique.
    Type: Grant
    Filed: May 6, 1985
    Date of Patent: April 29, 1986
    Assignee: Kloster Speedsteel Aktiebolag
    Inventor: Leif Westin
  • Patent number: 4582681
    Abstract: A hot isostatic pressing system including a hot isostatic pressing station having a high pressure container constituted by a vertical pressure-resistant cylinder closed at the top end thereof and a lower lid detachably fitted to the bottom of the pressure resistant cylinder and a treating chamber internally provided with a heater and enclosed by a heat insulating wall, and a mechanism for adjusting an atmospheric gas pressure and temperature of the pressing station into a condition suitable for the hot isostatic pressing of a work item accommodated in the treating chamber; a plurality of auxiliary stations each provided with an opening for receiving from beneath thereof the heat insulating wall of the treating chamber accommodating the internal heater and a work item, a support structure for supporting the heat insulating wall, and a mechanism for cooling the work item and internal heater in an inert gas atmosphere; a carriage for transferring the lower lid and work item or the lower lid, work item, heat insu
    Type: Grant
    Filed: October 21, 1982
    Date of Patent: April 15, 1986
    Assignee: Kabushiki Kaisha Kobe Seiko Sho
    Inventors: Akira Asari, Shiro Matsuura, Hidehiro Tsuzuki, Yohichi Inoue, Masato Moritoki, Takao Fujikawa, Junichi Miyanaga
  • Patent number: 4568516
    Abstract: An object is manufactured from a powdered material by isostatic pressing of a body, preformed from the powdered material, with a pressure medium, whereby the preformed body, in which at least the surface layer consists of a ceramic material in the form of a nitride, is surrounded by a casing which is rendered impenetrable to the pressure medium, before the isostatic pressing is carried out and the powder sintered. As the material in the casing there is used boron oxide or a glass containing boron oxide or a material forming glass while being heated, in which the content of boron oxide is sufficiently high for the glass--or the glass formed during heating--to be removable by water. The preformed body surrounded by the casing is subjected to a heat treatment for the formation of boron nitride on the surface of the preformed body, before the isostatic pressing is carried out. The casing is removed from the finished product by means of water or water vapor.
    Type: Grant
    Filed: February 7, 1984
    Date of Patent: February 4, 1986
    Assignee: ASEA Aktiebolag
    Inventors: Jan Adlerborn, Hans Larker, Jan Nilsson, Bertil Mattsson
  • Patent number: 4534936
    Abstract: A method for removal of organic binders from powder compacts is disclosed in which the compact is heated while the weight change is monitored and controlled. The heating is regulated so that the removal rate of the binder is optimized. The removal time can be shortened without creating defects in the powder compact.
    Type: Grant
    Filed: June 9, 1983
    Date of Patent: August 13, 1985
    Inventors: Elis Carlstrom, Agneta I. Johnsson, Leif A. G. Hermansson
  • Patent number: 4519839
    Abstract: A sintered high vanadium high speed steel with an excellent hardness and ductility of composition C 1.4-6.2%, W+2 Mo (W-equivalent) 10.0-24.0%, Cr 3.0-6.0%, V 8.5-28%, Co less than 17%, the remainder Fe and inevitable impurities, and a method of producing same.It can be produced by the steps of commingling the alloy constituents in the form of pulverulent oxides and carbon powder, heating the mixture in a stream of hydrogen, thereby reducing the mixture by the carbon and hydrogen simultaneously to yield an alloy powder, adjusting the composition and the grain size of the obtained alloy powder, pressing the alloy powder to a compact, sintered the compact in a vacuum, and finally converting the matrix of the sintered body into martensite by heat treatment.
    Type: Grant
    Filed: October 3, 1984
    Date of Patent: May 28, 1985
    Assignees: The Furukawa Electric Co., Ltd., Kanto Denka Kogyo Co., Ltd., Fujidie Co., Ltd.
    Inventors: Ishibachi Toyoaki, Yoshihara Minoru, Takuma Takashi, Fuke Yasunori, Maeda Masayuki
  • Patent number: 4478790
    Abstract: A method of manufacturing molded articles of metal alloys, especially of nickel-base alloys, chromium-base alloys, titanium-base alloys, and dispersion-hardened alloys. A powder of the alloy, or a blend of powders of alloy constituents, is mixed with one or more plastics, selected from thermoplastics, duroplastics, and internal lubricants to form an injectionable granulate compound, the plastic content amounting to about 30% to 50% by volume. The compound is prepared by dissolving the plastic in a solvent which will not attack the base material of the alloy, and by blending it with the metal powder, after which the solvent is evaporated. The injectionable granulate compound is then injection molded to form a molded article. By heat treatment at 600.degree. C. or below in inert gas the plastic is eliminated from the molded article. The article is then sintered. To improve its strength, the article may subsequently be subjected to hot isostatic pressing.
    Type: Grant
    Filed: May 3, 1982
    Date of Patent: October 23, 1984
    Assignee: MTU Motoren-und Turbinen-Union Munchen GmbH
    Inventors: Werner Huther, Axel Rossmann
  • Patent number: 4452756
    Abstract: A method for producing a machinable, high strength hot formed powdered ferrous base metal alloy is provided which comprises providing a particulate mixture consisting of, in weight percent, from about 1.0 to about 3.0 percent copper, from about 0.16 to about 0.35 percent sulfur, from about 0.4 to about 0.8 percent carbon, with the balance being iron plus from 0 to about 2 percent incidental impurities; forming this particulate mixture into a preformed article having a predetermined configuration; sintering the so-formed article at a temperature sufficient to produce the desired alloy; and subjecting the sintered article to a hot forming treatment to produce a hot formed, machinable, high strength ferrous base powdered metal alloy article having a density near theoretical.
    Type: Grant
    Filed: June 21, 1982
    Date of Patent: June 5, 1984
    Assignee: Imperial Clevite Inc.
    Inventor: Keith C. McLeod
  • Patent number: 4448747
    Abstract: A high density sintering method for powder molded products by applying preliminary sintering to powder molded products previously molded into a predetermined shape and then applying hot isostatic press process to the sintered products thereby producing high density sintered product which includes the steps of loading the powder molded products into a movable heating furnace equipped with at least one heating means and having a heat insulating structure, introducing the heating furnace into an atmosphere chamber, applying preliminary sintering to the powder molded products in the heating furnace by the heating means while conditioning the inside of the atmosphere chamber to a vacuum or predetermined gas atmosphere, subsequently removing the heating furnace while maintaining the inside thereof at a high temperature from the atmosphere chamber and directly introducing the furnace into a high pressure vessel, thereafter, applying the hot isostatic press process to the sintered products in the furnace while chargi
    Type: Grant
    Filed: September 1, 1982
    Date of Patent: May 15, 1984
    Assignee: Kabushiki Kaisha Kobe Seiko Sho
    Inventors: Masato Moritoki, Takao Fujikawa, Junichi Miyanaga