Plural Heating Steps Including Sintering Patents (Class 419/53)
  • 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: 4601875
    Abstract: Permanent magnetic materials of the Fe-B-R type are produced by:preparing an metallic powder having a mean particle size of 0.3-80 microns and a composition of, by atomic percent, 8-30% R (rare earth elements), 2-28% B, and the balance Fe, compacting, sintering at a temperature of 900-1200 degrees C., and aging at a temperature ranging from 350 degrees C. to the temperature for sintering. Co and additional elements M (Ti, Ni, Bi, V, Nb, Ta, Cr, Mo, W, Mn, Al, Sb, Ge, Sn, Zr, Hf) may be present.
    Type: Grant
    Filed: September 15, 1983
    Date of Patent: July 22, 1986
    Assignee: Sumitomo Special Metals Co., Ltd.
    Inventors: Hitoshi Yamamoto, Masato Sagawa, Setsuo Fujimura, Yutaka Matsuura
  • 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: 4594104
    Abstract: The present invention provides a method for producing a consolidated article composed of a transition metal alloy. The method includes the step of selecting a rapidly solidified alloy which is at least about 50% glassy. The alloy is formed into a plurality of alloy bodies, and these alloy bodies are compacted at a pressing temperature of not more than about 0.6 Ts (solidus temperature in .degree.C.) to consolidate and bond the alloy bodies together into a glassy metal compact having a density of at least about 90% T.D. (theoretical density). The compacted glassy alloy bodies are then heat treated at a temperature generally ranging from about 0.55-0.85 Ts, but, in any case, above the alloy crystallization temperature, for a time sufficient to produce a fine grain crystalline alloy structure in the compacted article.
    Type: Grant
    Filed: April 26, 1985
    Date of Patent: June 10, 1986
    Assignee: Allied Corporation
    Inventor: Derek Reybould
  • Patent number: 4591482
    Abstract: Pressure assisted sintering achieves full densification in short sinter times with low grain growth. This result is enabled by a stage of sintering to a condition of closed porosity (14) followed by a pressure assisted sinter (PAS) stage (16) carried out at a temperature close to, but just below, sinter temperature. Advantageously a small melt formation is induced by a brief temperature spiking (18) during the PAS stage to enable collapse of voids.
    Type: Grant
    Filed: August 29, 1985
    Date of Patent: May 27, 1986
    Assignee: Gorham International, Inc.
    Inventor: Andrew C. Nyce
  • Patent number: 4588551
    Abstract: An article comprising a first portion which is formed porously by sintering of an alloy or cermet material and a second portion which is formed of a metal and intimately bonds to the first portion. For example, the article is a rocker arm for an automotive internal combustion engine, in which first portion is the wear-resistant tip portion and the second portion the body portion. The second portion is formed by molten metal forging, with the sintered first portion set in the mould as an insert, such that the molten metal under pressure is forced to infiltrate into the pores of the sintered first portion at least in a region contiguous to the interface between the first and second portions. This article features very high strength of the bond at the interface between the first and second portions.
    Type: Grant
    Filed: December 5, 1984
    Date of Patent: May 13, 1986
    Assignee: Nissan Motor Co., Ltd.
    Inventors: Takaaki Iijima, Takeshi Nishiura, Ryuji Inomata, Eiji Tanaka, Hideaki Suzuki
  • 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: 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: 4483820
    Abstract: A process for making sintered metal articles of high strength in which a flowable mass of metallic particles is initially formed into a green compact having shape stability in a forming machine of the type used in the fabrication of sand cores in the metal casting field. The green compact is then subjected to sintering and the sintered body may be pressed, forged or mechanically shaped in other ways. The core blowing or core-sand slinging machine used to produce the green metal compact is surprisingly effective in producing a dense, reproducible structure in light of the fact that sand cores for casting purposes are intentionally made frangible to enable them to be removed effectively from the casting.
    Type: Grant
    Filed: January 29, 1981
    Date of Patent: November 20, 1984
    Assignee: Sintermetallwerk Krebsoge GmbH
    Inventor: Bernhard Schelb
  • 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: 4421717
    Abstract: A method is disclosed for making wear resistant, ferrous based parts (10) by molding a uniform mixture of ferrous based powder and binder material into a compacted shape, heating the compacted shape to remove the binder and to partially sinter the mixture to a strength of 1000-8000 psi, while maintaining a porosity of 20-40% at least along the outer region of the part, depositing a fluid suspension of wear resistant particles onto a surface zone of the shape, and heating the coated shape to bond the particles to the surface and fully sinter the part.
    Type: Grant
    Filed: June 10, 1982
    Date of Patent: December 20, 1983
    Assignee: Ford Motor Company
    Inventor: Vemulapalli D. N. Rao
  • Patent number: 4414028
    Abstract: A particulate mass to be sintered is imbedded in a mold which comprises a porous mass of particulate refractory material enclosed within a flexible membrane. Six press units are provided for applying compressive pressures externally to the mold, together or in sequence, whereby to subject the sinterable mass to pressures in the respective directions, under the control of a preprogrammed control unit which receives clock pulses from a source and stimulates the respective press units. A flexible heating coil imbedded in the mold is supplied with alternating current from a source to inductively heat up the sinterable mass and the adjacent mold material, to enable sintering to occur. The sinterable mass may have been precompacted into a self-supporting so-called "green compact", or it may be supported in a self-supporting shell carried within and forming part of the mold. The mold preferably comprises three layers having characteristics chosen so as to assist in heating up the sinterable mass uniformly.
    Type: Grant
    Filed: April 8, 1980
    Date of Patent: November 8, 1983
    Assignee: Inoue-Japax Research Incorporated
    Inventor: Kiyoshi Inoue
  • Patent number: 4393563
    Abstract: A method and material for the manufacture of improved bearing elements such as annular inner and outer bearing ring blanks for ball, roller and needle bearing assemblies comprising the steps of mixing a powder consisting substantially of iron with ferro-alloy powders of substantially smaller size, each ferro-alloy containing at least 80% iron and the balance being an alloying element, together with graphite powder and a lubricant, compacting the resulting mixture to form a preform, pre-sintering the preform, and then coating the sintered preform with a stop-off and lubricant. The preform is subjected to a plastic deformation of at least 50% in a cold (room temperature) forging operation to produce an article which is at least 98% dense and has approximately the shape of the finished article. This cold forged shape is resintered and annealed, after which the annealed and resintered shape is roll formed into substantially final dimensions.
    Type: Grant
    Filed: May 26, 1981
    Date of Patent: July 19, 1983
    Inventor: David T. Smith
  • Patent number: 4383854
    Abstract: A method of creating a controlled interior surface configuration of passages within a substrate, particularly cooling passages of nozzles or buckets of a gas turbine, involves the hot isostatic pressing of a leachable passage insert whose surface carries the female image of the desired interior surface configuration inside the substrate followed by leaching of the insert from the substrate.
    Type: Grant
    Filed: December 29, 1980
    Date of Patent: May 17, 1983
    Assignee: General Electric Company
    Inventors: Peter V. Dembowski, Peter W. Schilke
  • Patent number: 4373970
    Abstract: Copper base spinodal alloy strip of good strength and ductility is provided, the alloy containing 5 to 35 percent nickel, 7 to 13 percent tin, balance essentially copper, and having an unaged microstructure characterized by an equiaxed grain structure of substantially all alpha, face-centered-cubic phase with a substantially uniform dispersed concentration of tin and a substantial absence of tin segregation. The strip is prepared from copper alloy powder of the indicated composition by a process comprising the steps of compaction, sintering, cooling, rolling and annealing. The strip after aging may contain up to about 50 percent alpha plus gamma phase.
    Type: Grant
    Filed: November 13, 1981
    Date of Patent: February 15, 1983
    Assignee: Pfizer Inc.
    Inventors: Clive R. Scorey, Roy A. Smith
  • Patent number: RE32117
    Abstract: Process for manufacturing a forged article in which a preform is generated by filling a semi-rigid liner with powdered metal, providing the liner with a sealing element, and isostactically compressing the liner and its contents. The liner is then removed from the green preform, the preform is sintered, and the resulting sintered preform is forged.
    Type: Grant
    Filed: November 16, 1981
    Date of Patent: April 22, 1986
    Assignee: Wyman-Gordon Company
    Inventor: Elbert K. Weaver