Superconductor Patents (Class 29/599)
  • Patent number: 5802708
    Abstract: The present invention provides a method of producing high-strength and high-conductance copper and silver materials comprising the steps of combining a predetermined ratio of the copper with the silver to produce a composite material, and melt spinning the composite material to produce a ribbon of copper and silver. The ribbon of copper and silver is heated in a hydrogen atmosphere, and thereafter die pressed into a slug. The slug then is placed into a high-purity copper vessel and the vessel is sealed with an electron beam. The vessel and slug then are extruded into wire form using a cold hydrostatic extrusion process.
    Type: Grant
    Filed: May 30, 1996
    Date of Patent: September 8, 1998
    Assignee: The Regents of The University of California
    Inventors: Mary Ann Hill, John F. Bingert, Sherri A. Bingert, Dan J. Thoma
  • Patent number: 5786306
    Abstract: A method is provided for fabrication of superconducting oxides and superconducting oxide composites and for joining superconductors to other materials. A coating of a molten alloy containing the metallic elements of the oxide is applied to a substrate surface and oxidized to form the superconducting oxide. A material can be contacted to the molten alloy which is subsequently oxidized joining the material to the resulting superconducting oxide coating. Substrates of varied composition and shape can be coated or joined by this method.
    Type: Grant
    Filed: May 1, 1991
    Date of Patent: July 28, 1998
    Assignee: Massachusetts Institute of Technology
    Inventors: Wei Gao, John B. Vander Sande
  • Patent number: 5786305
    Abstract: A process for manufacturing a wire made of oxide which is applicable for manufacturing a superconducting coil or the like. The process includes steps comprising preparing a mass of oxide having superconductivity from powder material, covering the mass of oxide with a metal pipe, and then reducing the diameter of the metal pipe containing the mass of oxide therein into a wire form by such plastic deformation that exert mainly compressive strain upon the metal pipe. The mass of oxide may be a compound oxide having Perovskite-type crystal structure exhibiting superconductivity. The metal pipe may be made of a metal selected from a group comprising Cu, Al, Nb, V, Mo, Ta, and Ag and of an alloy including these metals as the base. The mass of oxide may be produced by steps including extruding a powder material into a rod shape and then sintering the molded rod at a temperature ranging from 700.degree. to 1,000.degree. C.
    Type: Grant
    Filed: May 4, 1993
    Date of Patent: July 28, 1998
    Assignee: Sumitomo Electric Industries Ltd.
    Inventor: Kazuhiko Hayashi
  • Patent number: 5758405
    Abstract: The invention relates to a processing method for fabricating a superconducting magnetic coil using a mandrel having a consumable component. When exposed to a final processing step, the consumable component is mechanically weakened through oxidation or thermal decomposition. The mandrel can then be easily removed from the coil without straining the conductor, thus preserving the coil's electrical and mechanical properties.
    Type: Grant
    Filed: April 28, 1995
    Date of Patent: June 2, 1998
    Assignee: American Superconductor Corporation
    Inventors: Bruce R. Bent, Craig John Christopherson, Eric R. Podtburg, Derek Patrick Daly
  • Patent number: 5756427
    Abstract: High-Tc superconducting ceramic oxide products and macroscopic and microscopic methods for making such high-Tc superconducting products. Completely sealed high-Tc superconducting ceramic oxide provides are made by a macroscopic process including the steps of pressing a superconducting ceramic oxide powder into a hollow body of a material inert to oxygen; heat treating the superconducting ceramic oxide powder packed body under conditions sufficient to sinter the ceramic oxide powder; and then sealing any openings of the body. Optionally, a waveform or multiple pulses of alternate magnetic filed can be applied during the heat treatment.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: May 26, 1998
    Inventor: Dawei Zhou
  • Patent number: 5747181
    Abstract: A superconductive article is made from interconnected superconductive, metallic tapes. The tapes preferably are mechanically joined and electrically interconnected by a plurality of superconductive interconnections that extend between the tapes. The interconnections are formed by overlapping the edges of two tapes and forming a plurality of superconductive welds between the tapes in the overlapping regions. Articles of this invention may be formed from superconductive tapes made from Nb.sub.3 Sn having superconductive interconnections that also include Nb.sub.3 Sn.
    Type: Grant
    Filed: July 24, 1995
    Date of Patent: May 5, 1998
    Assignee: General Electric Company
    Inventor: Thomas Robert Raber
  • Patent number: 5744427
    Abstract: In a method of preparing a thallium oxide superconductor having components of Tl-Bi-Ca-Sr-Cu-O or Tl-Bi-Pb-Ca-Sr-Cu-O from raw material powder, the raw material powder is subjected to first heat treatment, then exposed to a compressive load, and thereafter subjected to second heat treatment. Thus, a thallium oxide superconductor having a high critical current density can be obtained.
    Type: Grant
    Filed: April 25, 1994
    Date of Patent: April 28, 1998
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventor: Yasuko Torii
  • Patent number: 5733389
    Abstract: A method for manufacturing an aluminum alloy conductor for use at ultra low temperature which involves the steps of adding at least one of the metallic and semimetallic effective elements selected from the group consisting of B, Ca, Ce, Ga, Y, Yb and Th, in a total amount of 6 to 200 weight ppm, into a previously prepared molten high purity aluminum having a purity of not less than 99.98 wt % to thereby obtain a molten metal mixture; casting the molten metal mixture to thereby obtain a casting; subjecting the casting to extrusion working at 150.degree. C. to 350.degree. C. in an area reduction ratio of 1:10 to 1:150 whereby an extrusion worked product is formed; and annealing the extrusion worked product at a temperature of 250.degree. C. to 530.degree. C. for 3 to 120 minutes, whereby an aluminum alloy conductor for use at ultra low temperature is obtained.
    Type: Grant
    Filed: May 18, 1995
    Date of Patent: March 31, 1998
    Assignees: Sumitomo Chemical Co., Ltd., Texas A & M University System
    Inventors: Akihiko Takahashi, Hitoshi Yasuda, Karl Theodore Hartwig, Lacy Clark McDonald
  • Patent number: 5718034
    Abstract: A new design for an aluminum stabilized superconductor which embeds the superconducting cable within a high purity aluminum stabilizer. This stabilizer is, in turn, partially surrounded by an aluminum alloy sheath. The aluminum alloy sheath is constructed and arranged so that at least one exterior surface of the stabilizer is open for exposure to a coolant. Preferably, this open exterior surface of the stabilizer will be knurled for greater cooling efficiency.
    Type: Grant
    Filed: September 12, 1996
    Date of Patent: February 17, 1998
    Assignee: The Babcock & Wilcox Company
    Inventors: Xianrui Huang, Gregory Alan Lehmann, Yury Lvovsky, Ronald Glenn Wood
  • Patent number: 5706571
    Abstract: A sheathed twisted superconductor with a high critical temperature is made from a billet obtained by assembling square cross-section single strands in a square cross-section metal tube. The multistrand obtained by drawing the billet through a roller die is twisted with a particular lay and rolled using rollers the diameter of which is much greater than the twist lay. The sheathed twisted superconductor obtained by this method is intended for variable current applications.
    Type: Grant
    Filed: September 13, 1996
    Date of Patent: January 13, 1998
    Assignee: Alcatel Alsthom Compagnie Generale D'Electricite
    Inventors: Gerard Duperray, Erick Beghin, Denis Legat, Peter Friedrich Herrmann
  • Patent number: 5689875
    Abstract: Large amounts of stabilizing copper may be added to a superconducting core using an economical cladding process. One or more cladding strips of copper are bonded directly to the core without the use of a bonding agent. The copper cladding is fused to the core at a late stage in the fabrication of the superconductor by the simultaneous application of heat and pressure using conventional rolling apparatus. Multiple cladding layers may be sequentially applied to further increase the volume of copper present in the superconductor.
    Type: Grant
    Filed: June 14, 1996
    Date of Patent: November 25, 1997
    Assignee: IGC Advanced Superconductors
    Inventor: Hem C. Kanithi
  • Patent number: 5686394
    Abstract: A continuous method for manufacturing an elongated superconducting campsite composed of a superconductor consisting of compound oxided and a metal sheath surrounding the superconductor, including the steps of kneading a material powder of superconducting compound oxide with a binder, continuously shaping the resulting kneaded paste into an elongated pre-form by an extruder or by coating technlque, heating the pre-form continuously to remove said binder, wrapping the pre-form with a metallic sheet, and then subjecting the pre-form from wrapped with the metallic sheet to sintering operation to sinter said material powder.
    Type: Grant
    Filed: June 3, 1993
    Date of Patent: November 11, 1997
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kenichiro Sibata, Nobuyuki Sasaki, Shuji Yazu, Tetsuji Jodai
  • Patent number: 5683969
    Abstract: A strongly-linked polycrystalline oxide superconductor article includes an oxide superconductor selected from the group consisting 124-type and 247-type oxide superconductors having fine, highly aligned oxide superconductor grains less than 50 .mu.m along a longest dimension. The oxide superconductor article has at least a 25% retention of critical current density in a 0.1 Tesla field.
    Type: Grant
    Filed: May 12, 1992
    Date of Patent: November 4, 1997
    Assignee: American Superconductor Corporation
    Inventors: Lawrence J. Masur, Eric R. Podtburg
  • Patent number: 5674814
    Abstract: The present invention is directed to a process for producing high temperature superconducting ceramic materials. More particularly, the present invention is directed to a process that enhances the densification of Bi.sub.1.8 Pb.sub.0.4 Sr.sub.2 Ca.sub.2 Cu.sub.3 O.sub.10 "BSCCO" ceramics.
    Type: Grant
    Filed: November 14, 1994
    Date of Patent: October 7, 1997
    Assignee: University of Chicago
    Inventors: Michael T. Lanagan, John J. Picciolo, Stephen E. Dorris
  • Patent number: 5656380
    Abstract: A superconductive article is made from interwoven superconductive, metallic tapes. The interwoven tapes are electrically interconnected by a plurality of superconductive interconnections that extend between the interwoven tapes. Articles of the invention may be formed from tapes comprising superconductive Nb.sub.3 Sn having Nb.sub.3 Sn interconnections.
    Type: Grant
    Filed: March 20, 1995
    Date of Patent: August 12, 1997
    Assignee: General Electric Company
    Inventors: Thomas Robert Raber, Mark Gilbert Benz, Howard Roscoe Hart, Jr.
  • Patent number: 5654098
    Abstract: A superconducting wire saved in weight and enhanced in mechanical properties is provided without damaging electric and thermal characteristics as an Al stabilizer, and further a method for producing the same, a high strength Al sintered alloy and powders used for the process are provided. A superconducting wire comprising an Al alloy of a high purity Al in which a small amount of ceramic ultrafine particles are dispersed and superconducting filaments embedded in the Al alloy, in which a large number of the ceramic ultrafine particles are dispersed in the area of 1 .mu.m.sup.2, and the areas of 1 .mu.m.sup.2 in which a large number of the ceramic ultrafine particles are dispersed, are formed over nearly the whole of the alloy.
    Type: Grant
    Filed: June 7, 1996
    Date of Patent: August 5, 1997
    Assignee: Hitachi, Ltd.
    Inventors: Yasuhisa Aono, Fumio Iida, Shinzo Ikeda, Takahiko Kato, Masakiyo Izumiya, Hideyo Kodama
  • Patent number: 5647116
    Abstract: A non-superconductive Ag-based sheath formed surrounding a superconducting tape or wire is stripped by placing a Bi- or Pb-based metal material on the Ag-based sheath to be removed; and then heating the Bi- or pb-based metal material to 250.degree. C.-450.degree. C. to dissolve the Ag-based sheath; and removing the dissolved Ag-based sheath.
    Type: Grant
    Filed: September 7, 1995
    Date of Patent: July 15, 1997
    Assignee: National Science Council
    Inventors: Chin-Hai Kao, Horng-Yi Tang
  • Patent number: 5639714
    Abstract: A method of producing a Bi-Pb-Sr-Ca-Cu oxide superconductor by thermally treating raw material comprises steps of performing first plastic deformation on the raw material, performing first heat treatment on the material being subjected to the first plastic deformation, performing second plastic deformation on the material being subjected to the first heat treatment, and performing second heat treatment on the material being subjected to the second plastic deformation.
    Type: Grant
    Filed: June 2, 1995
    Date of Patent: June 17, 1997
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takeshi Hikata, Ken-ichi Sato, Hidehito Mukai, Nobuhiro Shibuta, Kazuya Ohmatsu, Masayuki Nagata, Satoshi Takano, Yoshikado Hosoda, Hajime Hitotsuyanagi, Maumi Kawashima
  • Patent number: 5628836
    Abstract: The method of preparing an NB.sub.3 Al superconducting wire comprises the steps of passing an Nb/Al composite wire consisting of an Nb metal or an Nb alloy and an Al metal or an Al alloy through a furnace for heating the same from the room temperature to a prescribed temperature, subsequently passing the same through the furnace for holding the same at the prescribed temperature, and subsequently passing the same through a cooling part for cooling the same from the prescribed temperature to the room temperature, and these steps are continuously carried out by continuously moving the wire. According to the present invention, it is possible to obtain an Nb.sub.3 Al superconducting wire having homogeneous characteristics along its overall width with a high critical current density.
    Type: Grant
    Filed: November 18, 1994
    Date of Patent: May 13, 1997
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Naoki Ayai, Yuichi Yamada
  • Patent number: 5627141
    Abstract: In order to obtain a ceramics system superconducting wire, a bulk type ceramics system superconductor or its precursor previously treated to have orientativity in its crystal structure is reduced in diameter in a state charged in a metallic pipe, thereby being elongated, and then heat treated. In the as-formed superconducting wire, crystal orientativity of a bulk formed of the superconductor or its precursor is maintained, whereby it is possible to obtain a superconducting wire having high critical current density. In order to further improve the critical current density, it is effective that the diameter reduction working step and the heat treatment step are alternately repeated a plurality of times.
    Type: Grant
    Filed: May 22, 1995
    Date of Patent: May 6, 1997
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kazuhiko Hayashi, Hisao Nonoyama
  • Patent number: 5612291
    Abstract: A superconductive device for helping shield magnetic field comprises at least two members; a layer containing superconductive oxide over each of said members; means for connecting said members to form a substrate; and means for connecting said layers containing superconductive oxide along a joint in which said members are connected.
    Type: Grant
    Filed: April 20, 1994
    Date of Patent: March 18, 1997
    Assignee: NGK Insulators, Ltd.
    Inventors: Shoji Seike, Hideki Shimizu, Makoto Tani
  • Patent number: 5610123
    Abstract: In a method of preparing a bismuth oxide superconducting wire comprising the steps of filling raw material powder into a metal sheath, working the same into a wire by performing deformation processing in this state, and heat treating the wire, the raw material powder is heat treated before the step of working the raw material powder into a wire by performing deformation processing, so that the ratio of a 2212 phase, containing Bi or (Bi,Pb), Sr, Ca and Cu in composition ratios of about 2:2:1:2, to a 2223 phase, containing Bi or (Bi,Pb), Sr, Ca and Cu in composition ratios of about 2:2:2:3, is 75 to 90:10 to 25, in order to prepare a wire which is excellent in critical current density as well as in critical current.
    Type: Grant
    Filed: February 8, 1995
    Date of Patent: March 11, 1997
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kenichi Sato, Takeshi Hikata, Munetsugu Ueyama
  • Patent number: 5600095
    Abstract: A conductor splice and splice support structure and method of assembly for use with cable-in-conduit superconductor cable of the type having a plurality of spaced sub-cables each including stabilizer and superconductor strands in an annular tube. Two transition ramp members, each having a cross section varying from a first end conforming to the cable configuration to a second end having an enlarged, oval, configuration have a plurality of surface grooves each sized to hold one sub-cable. Between the two transition ramp members is provided a main support member having grooves aligned with the transition members grooves. The main support member grooves are sized to hold two overlapping sub-cables. Preferably, a braid of superconductor material is placed around the overlapping sub-cable ends. The space within the grooves surrounding the sub-cables is preferably filled with solder.
    Type: Grant
    Filed: July 18, 1994
    Date of Patent: February 4, 1997
    Assignee: Lockhead Martin Corporation
    Inventors: Michael W. Dew, Dennis W. Lieurance, Donald C. Rix
  • Patent number: 5592732
    Abstract: An electrical connection between first and second members of superconductive material, such as niobium, is made by coating each member with an indium-lead-tin alloy solder. Each member is coated by initially applying a layer of either an indium-lead alloy or indium to a surface of the member. Then the surface is mechanically worked to break up any oxide coating that is underneath the applied layer. Next a lead-tin alloy or tin is alloyed with the applied layer to form a resultant surface layer of a indium-lead-tin alloy. The first and second members are placed in contact with each other and their respective surface layers of the indium-lead-tin alloy are melted to produce a bond therebetween. A bond form by this method also is described.
    Type: Grant
    Filed: October 26, 1994
    Date of Patent: January 14, 1997
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Arthur C. Leuthold, Ronald T. Wakai
  • Patent number: 5583319
    Abstract: A low resistance splice for electrically connecting the ends of two superconducting cables and a method for making the splice. Two cables formed from superconducting material are positioned in close proximity, either overlapping or axially aligned and extending in opposite directions away from the splice. At least one strand of superconducting material is wrapped over both cables in a pressure relationship assuring good electrical contact between cable ends and strands. Solder is melted and applied to hold the strands against the cables. Where the cables overlap, solder may be used at the overlap interface to add mechanical strength. The strands may be in the form of a helical winding around overlapping cable ends or in the from of a braided tube surrounding and pressed against either overlapping or axially aligned cables. In the axial embodiment, the cables with the strand wrap may be pressed into a slot and the slot filled with solder to hold the cables and strands in position.
    Type: Grant
    Filed: October 21, 1993
    Date of Patent: December 10, 1996
    Inventor: Dennis W. Lieurance
  • Patent number: 5571602
    Abstract: A superconducting magnet shield includes a plurality of overlapping NbTi sheets welded together with a plurality of welds extending along elongated parallel slots in the overlap region with the slots extending in the direction of superconducting current flow.
    Type: Grant
    Filed: December 29, 1994
    Date of Patent: November 5, 1996
    Assignee: General Electric Company
    Inventors: Phillip W. Eckels, Delton A. Grey, Jr., Christopher G. King, Anthony Mantone, O'Neil T. McClam, Granville G. Ward, Jr.
  • Patent number: 5552376
    Abstract: Powder having a composition in which the contents of Sr, Ca and Cu are increased so that an Sr-Ca-Cu-O phase is precipitated in addition to a 2223 phase of (Bi, Pb)-Sr-Ca-Cu is charged in a metal sheath, and this metal sheath is plastic-worked, then subjected to a primary heat treatment, then plastic-worked and further subjected to a secondary heat treatment. In the as-obtained bismuth oxide superconducting wire, pinning points based on the Sr-Ca-Cu-O phase are introduced into the superconductor, whereby magnetic field characteristic of the critical current density is improved.
    Type: Grant
    Filed: November 28, 1994
    Date of Patent: September 3, 1996
    Assignees: Sumitomo Electric Industries, Ltd., Director General of National Research Institute for Metals of Science and Technology Agency of Japan, Research Development Corporation of Japan
    Inventors: Takeshi Kato, Kenichi Sato
  • Patent number: 5551144
    Abstract: A method of forming a crepe paper insulated superconducting magnet coil with fifty percent overlap crepe paper wrapping with the paper wound superconductor subsequently wound into a coil on a coil form pocket using the crepe paper wrap as an insulating and friction reducing component.
    Type: Grant
    Filed: December 29, 1994
    Date of Patent: September 3, 1996
    Assignee: General Electric Company
    Inventors: Deborah R. Mantone, Barbara L. Myers
  • Patent number: 5550102
    Abstract: A method of manufacturing a superconductor is carried out by first preparing a material composed of Y.sub.1 Ba.sub.2 Cu.sub.3 O.sub.7. This material is heated/molten in a platinum crucible. A melt thus obtained is drawn out from a high-temperature frame provided above the platinum crucible and heated to a temperature exceeding the melting point of the material. The melt thus drawn out is cooled by natural standing, to be solidified. As the result, an elongated superconductor composed of Y.sub.1 Ba.sub.2 Cu.sub.3 O.sub.7 can be obtained. This superconductor enters a superconductive state at 90 K.
    Type: Grant
    Filed: September 9, 1992
    Date of Patent: August 27, 1996
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Yoshihiro Nakai, Kazuo Sawada, Kazuhiko Hayashi, Masanobu Nishio
  • Patent number: 5531015
    Abstract: A process for manufacturing superconducting magnetic coils from strain-tolerant, superconducting multi-filament composite conductors is described. The method involves winding the precursor to a multi-filament composite conductor and an insulating material or its precursor around a mandrel in order to form a coil, and then exposing the coil to high temperatures and an oxidizing environment. The insulating material or its precursor is chosen to permit exposure of the superconductor precursor filaments to the oxidizing environment, and to encase the matrix-forming material enclosing the filaments, which is reversibly weakened during processing.
    Type: Grant
    Filed: January 28, 1994
    Date of Patent: July 2, 1996
    Assignee: American Superconductor Corporation
    Inventors: Michael D. Manlief, Gilbert N. Riley, Jr., John Voccio, Anthony J. Rodenbush
  • Patent number: 5525583
    Abstract: A superconducting magnetic coil includes a plurality of sections positioned axially along the longitudinal axis of the coil, each section being formed of an anisotropic high temperature superconductor material wound about a longitudinal axis of the coil and having an associated critical current value that is dependent on the orientation of the magnetic field of the coil. The cross section of the superconductor, or the type of superconductor material, at sections along the axial and radial axes of the coil are changed to provide an increased critical current at those regions where the magnetic field is oriented more perpendicularly to the conductor plane, to thereby increase the critical current at these regions and to maintain an overall higher critical current of the coil.
    Type: Grant
    Filed: February 7, 1994
    Date of Patent: June 11, 1996
    Assignee: American Superconductor Corporation
    Inventors: Dawood Aized, Robert E. Schwall
  • Patent number: 5508254
    Abstract: Disclosed herein is a method of preparing an oxide superconducting wire comprising the steps of coating a powder material for forming an oxide superconductor with a metal, performing deformation processing on the metal-coated powder material thereby obtaining a tape-type wire material, superposing a plurality of such tape-type wire materials, performing first heat treatment on the plurality of superposed tape-type wire materials while simultaneously diffusion-bonding the metallic coats to each other, then performing deformation processing on the plurality of superposed tape-type wire materials, and performing second heat treatment on the plurality of deformation-processed tape-type wire materials. Preferably the oxide superconductor to be obtained is a bismuth oxide superconductor having a 2223 composition in a composition of Bi-Sr-Ca-Cu or (Bi,Pb)-Sr-Ca-Cu, and the powder material consists of a superconducting phase, which is mainly composed of a 2212 phase, and non-superconducting phases.
    Type: Grant
    Filed: August 16, 1994
    Date of Patent: April 16, 1996
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kenichi Sato, Hidehito Mukai, Takeshi Hikata
  • Patent number: 5504984
    Abstract: A method of manufacturing an Nb.sub.3 Al superconducting wire includes a step of forming a wire by a jelly-roll process, a first thermal step of heating the obtained wire at a temperature of 500.degree. to 700.degree. C. for at least 10 hours for diffusing Al in Nb while suppressing formation of Nb.sub.3 Al, and a second thermal step of heating the wire, after the first thermal step, at a temperature of 800.degree. to 1050.degree. C. for about 0.01 to 10 hours, thereby forming Nb.sub.3 Al. In the jelly-roll process, a sheet of Nb and a sheet of Al are lap-wound on a copper core. The material obtained by such lap winding is inserted in a copper pipe, and then subjected to drawing. The drawn wire is cut to obtain a plurality of segments. The plurality of segments are bundled and charged in a copper pipe, and then subjected to drawing. The resulting drawn wire is subjected to the first and second thermal steps.
    Type: Grant
    Filed: December 13, 1993
    Date of Patent: April 9, 1996
    Assignees: Sumitomo Electric Industries, Ltd., Japan Atomic Energy Research Institute
    Inventors: Yuichi Yamada, Toshinari Ando, Yoshikazu Takahashi, Masataka Nishi, Hiroshi Tsuji, Hideo Nakajima
  • Patent number: 5501746
    Abstract: A process for preparing a superconducting wire having improved superconducting characteristics in shortened period of time at a reduced cost, which comprises the steps of forming a plurality of holes in each of Cu base metal plates, stuffing the plates in a supporting container to form a stacked body of the plates with their holes aligned with each other, stuffing a superconductor or a material convertible into a superconductor by a heat treatment into the resulting through-holes of the stacked body, evacuating and sealing the supporting container to form a composite billet, and processing the composite billet in a usual manner to give a superconducting wire.
    Type: Grant
    Filed: January 30, 1995
    Date of Patent: March 26, 1996
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Kunihiko Egawa, Yoshio Kubo, Takayuki Nagai, Fusaoki Uchikawa, Shoji Miyashita, Hiroko Higuma
  • Patent number: 5500995
    Abstract: A method of producing weldless resonating monolithic cavity comprising the steps of: arranging a die which can be disassembled into sectors and having the form of the internal cavity of the resonator; spinning a foil by using said die so as to provide a monolithic weldless body of metal sheet which coats exactly and completely the die; and disassembling and removing the sectors of the die through one opening of the resonator.
    Type: Grant
    Filed: November 5, 1993
    Date of Patent: March 26, 1996
    Assignee: Istituto Nazionale Di Fisica Nucleare
    Inventors: Vincenzo Palmieri, Renato Preciso, Vladimir L. Ruzinov, Sergei Y. Stark, Il'Ya I. Kulik
  • Patent number: 5491127
    Abstract: A composite superconducting wire using ceramic superconductor material in which one or more elongated superconductor material are accommodated in one or more grooves formed on an elongated reinforcing member so that a long size superconductor wire can be provided. Various methods of producing such composite superconductor wire are also disclosed.
    Type: Grant
    Filed: February 3, 1995
    Date of Patent: February 13, 1996
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Minoru Yokota, Masayuki Nagata, Shigeo Saito, Yuichi Yamada
  • Patent number: 5476208
    Abstract: Method for forming welded joints on superconducting foils to form long lengths of foil for use in superconducting magnet tapes including fixturing for controlling the accurate positioning of sheared foils and control of the overlap to be welded.
    Type: Grant
    Filed: November 8, 1993
    Date of Patent: December 19, 1995
    Assignee: General Electric Company
    Inventors: Neil G. Fiddes, Christopher G. King, Anthony Mantone, Frank D. Shaffer
  • Patent number: 5475915
    Abstract: A cylindrical billet of superconducting material is enclosed by a copper sheath circumferentially, and by a lid and nose of copper at its longitudinal ends. A short cylindrical nose piece of lesser diameter than the billet, is attached at the billet's front end. At the rear end of the billet, an annular ring of copper is positioned. The billet is enclosed in a liner leading to a convergent conical die. Longitudinal force is applied by a ram to the annular ring, which pushes against the outer periphery of the billet at the rear end in a direction toward the die orifice. The stepped nose piece deforms against the die. During an initial period wherein no extrusion takes place, the nose piece exerts an opposite reactive force on the center of the billet, moving the center material toward the ram. As a result of these two opposite actions on the billet, the central longitudinal portion of the billet is pushed back (upset) toward the ram and deforms into the opening of the annular ring.
    Type: Grant
    Filed: October 31, 1994
    Date of Patent: December 19, 1995
    Assignee: IGC Advance Superconductors, Inc.
    Inventor: Peter Valaris
  • Patent number: 5474975
    Abstract: A method for manufacturing an elongated member from a superconducting ceramic material comprising the steps of providing a hollow supporting body of metal or a metallic alloy having a hollow inside section therein, introducing a superconducting ceramic material into the hollow inside section of the hollow supporting body, drying the above liquid, so that the superconducting ceramic material is coated on the inside of the supporting body; and firing the supporting body and the ceramic material in an oxidizing atmosphere.
    Type: Grant
    Filed: February 22, 1990
    Date of Patent: December 12, 1995
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventor: Shumpei Yamazaki
  • Patent number: 5462920
    Abstract: In order to prevent inflation of a metallic coating during heat treatment so that no ununiformity is caused in the critical current density in a method of preparing an oxide superconducting wire which is obtained by heat treating and sintering metal-coated raw material powder for an oxide superconductor, raw material powder (5) for an oxide superconductor is filled up in a metal billet (1), which in turn is degassed and sealed in the degassed state, elongated with application of hydrostatic extrusion, and then heat treated.
    Type: Grant
    Filed: August 24, 1994
    Date of Patent: October 31, 1995
    Assignee: Sumitomo Electric Industries, Inc.
    Inventors: Hidehito Mukai, Kenichi Sato, Nobuhiro Shibuta
  • Patent number: 5434130
    Abstract: In a method of preparing an oxide superconducting wire comprising the steps of filling up raw material powder for an oxide superconductor in a metal sheath and rolling the same in this state, frictional force on surfaces of rolls employed for rolling is increased in the rolling step in order to improve denseness of the raw material powder, thereby improving the critical current density of the oxide superconducting wire. In order to increase the frictional force, films having large frictional force are formed on the roll surfaces, a coating material is applied to the roll surfaces during rolling, or the roll surfaces are roughened, for example.
    Type: Grant
    Filed: January 25, 1994
    Date of Patent: July 18, 1995
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takeshi Hikata, Kenichi Sato
  • Patent number: 5434129
    Abstract: A method of producing a high temperature long length coil of superconductor wire is disclosed. The method utilizes the "powder-in-tube" method or a similar method to form a wire. The wire is then shaped into rectangular form and wound around a mandrell. Rings, having a gap exposing the superconductor inside the silver or silver alloy tube are formed by cutting the wound wire and the rings are pressed to their final thickness. Each ring is then coated with an insulator and filed on both an outer side of one end of the gap and on an inner side of the other end of the gap. The rings are then positioned adjacent one another such that the gaps are staggered. They are placed in a manner in which the exposed superconductor on an outer side of one ring is in contact with the exposed superconductor on the inner side of an adjacent ring. The rings are then clamped together and heated to merge the superconducting material by diffusion. A long length coil is thus formed from the rings that are clamped.
    Type: Grant
    Filed: September 23, 1993
    Date of Patent: July 18, 1995
    Assignee: Advanced Superconductors, Inc.
    Inventors: Leszek Motowidlo, Pradeep Haldar
  • Patent number: 5434128
    Abstract: A superconductive article is made by inserting a rigid mandrel into an internal cavity of a first metallic tube, said tube having an interior surface and an exterior surface, said interior surface defining the interior cavity, forming a layer of a superconductive material or superconductive precursor upon the exterior surface of said first metallic tube, machining the layer of superconductive material or superconductive precursor to a predetermined diameter to form an intermediate article configured for insertion into a second metallic tube having an interior diameter corresponding to the predetermined diameter, inserting the machined intermediate article into a second metallic tube having an internal diameter corresponding to the predetermined diameter of the intermediate article to form a composite intermediate article, reducing or ironing the composite intermediate article to a predetermined cross-sectional diameter, and sintering the reduced or ironed composite intermediate article at temperatures and for
    Type: Grant
    Filed: December 17, 1993
    Date of Patent: July 18, 1995
    Assignee: The United States Department of Energy
    Inventors: David A. Korzekwa, John F. Bingert, Dean E. Peterson, Haskell Sheinberg
  • Patent number: 5432150
    Abstract: High-Tc superconducting ceramic oxide products and macroscopic and microscopic methods for making such high-Tc superconducting products. Completely sealed high-Tc superconducting ceramic oxide products are made by a macroscopic process including the steps of pressing a superconducting ceramic oxide powder into a hollow body of a material inert to oxygen; heat treating the superconducting ceramic oxide powder packed body under conditions sufficient to sinter the ceramic oxide powder; and then sealing any openings of the body. Optionally, a waveform or multiple pulses of alternate magnetic field can be applied during the heat treatment.
    Type: Grant
    Filed: June 14, 1993
    Date of Patent: July 11, 1995
    Inventor: Dawei Zhou
  • Patent number: 5426093
    Abstract: A composite superconducting wire using ceramic superconductor material in which one or more elongated superconductor material are accommodated in one or more grooves formed on an elongated reinforcing member so that a long size superconductor wire can be provided. Various methods of producing such composite superconductor wire are also disclosed.
    Type: Grant
    Filed: May 2, 1991
    Date of Patent: June 20, 1995
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Minoru Yokota, Masasyuki Nagata, Shigeo Saito, Yuichi Yamada
  • Patent number: 5424282
    Abstract: A process for producing a composite oxide superconducting wire is disclosed, which comprises the steps of compacting material powder for an oxide superconductor in a noble metal pipe; heating the metal pipe filled with the material powder at a temperature ranging between an upper limit corresponding to the lowest melting point of any one of constituent components in the material powder and a lower limit which is lower by 100.degree. C. than said upper limit to sinter the material powder and cooling the product at a cooling velocity of less than 50.degree. C./min, and further including a series of wire-drawing, annealing and sintering steps. Furthermore, an intermediate layer of noble metal can be interposed between the oxide superconductor and the metal pipe.
    Type: Grant
    Filed: February 22, 1994
    Date of Patent: June 13, 1995
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Susumu Yamamoto, Teruyuki Murai, Nozomu Kawabe, Tomoyuki Awazu, Shuji Yazu, Tetsuji Jodai
  • Patent number: 5419974
    Abstract: A component 10 for making Al5 Nb.sub.3 Sn superconducting wire is of plane-filling cross-section after removing temporary additions 6, 7. It consists of a central pillar 1 of aluminium (later replaced by tin) surrounded by a two-deep array of polygonal copper columns 2/2a containing niobium rods. Many (e.g. 61) components 10 are stacked together and extruded. The niobium rods adopt and retain a uniform distribution with minimum intervening material. On heat-treatment of the whole, the tin diffuses over a relatively short path and hence consistently into the rods, whereby there is formed a kilofilament Nb.sub.3 Sn wire.
    Type: Grant
    Filed: January 5, 1993
    Date of Patent: May 30, 1995
    Assignee: British Technology Group Ltd.
    Inventors: Colin R. Walters, Jan E. Evetts, Francis J. V. Farmer, Thomas J. Hawksley
  • Patent number: 5409890
    Abstract: Improvement in a process for producing a sintered elongated article by the steps comprising filling a metal pipe with a material powder, carrying out plastic deformation of the metal pipe and then subjecting the material powder in deformed metal pipe to sintering. In the invention, the step of the plastic deformation includes at least one deformation satge carried out under a hot condition.
    Type: Grant
    Filed: September 17, 1993
    Date of Patent: April 25, 1995
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Susumu Yamamoto, Nozomu Kawabe, Tomoyuki Awazu, Teruyuki Murai
  • Patent number: 5401717
    Abstract: This invention is related to the preparation of an elongate conductor having a silver sheath, and a core of an aligned polycrystalline oxide superconductor having the approximate formula Bi.sub.2-x Pb.sub.x Sr.sub.2-a L.sub.a+b Ca.sub.1-b Cu.sub.2 O.sub.y where y is from 7.5 to 8.5, and L is a lanthanide. A powder mixture is formed comprised of a first portion of a superconducting bismuth oxide compound that can be reaction-sintered to form the core oxide superconductor, and a second portion of oxides suitable for reacting with the first portion to form the core oxide superconductor. An elongate body is formed having a silver sheath, and a core of the mixture. The body is deformed to align the first portion, and heated to reaction-sinter the first and second portions to form the core oxide superconductor.
    Type: Grant
    Filed: February 14, 1994
    Date of Patent: March 28, 1995
    Assignee: General Electric Company
    Inventor: Kenneth W. Lay
  • Patent number: 5398398
    Abstract: A superconducting joint includes a niobium-tin superconducting composite member, a niobium-tin superconducting wire diffusion bonded to the superconducting composite, a spacer diffusion bonded to the superconducting wire, a support diffusion bonded to the spacer and a superconducting member in electrical contact with the superconducting composite. According to the method of the invention, a wire comprising unreacted niobium and tin is machined to form a tapered end having a first tapered surface exposing the wire interior and an opposing surface. A complementary spacer having the taper substantially similar to that of the wire is assembled with the wire so that the tapered wire and the tapered spacer in surface contact with one another such that the spacer occupies the area of the wire removed by machining and the exposed tapered surface remains still exposed.
    Type: Grant
    Filed: January 10, 1994
    Date of Patent: March 21, 1995
    Assignee: Massachusetts Institute of Technology
    Inventors: John E. C. Williams, Alexander Zhukovsky, Ronald De Rocher