Process Of Making Wire, Tape, Cable, Coil, Or Fiber Patents (Class 505/430)
  • Patent number: 5811376
    Abstract: A process for making a superconducting fiber or wire (10) is provided. The superconducting fiber or wire (10) has a superconducting core (12) and a glass cladding outer layer (14). The process comprises melting a superconducting composition (16) and a glass composition (18) and simultaneously drawing the compositions from a bushing (26) with the glass cladding layer (14) surrounding the superconducting core (12). The wire (10) is then annealed to create a superconducting crystalline phase.
    Type: Grant
    Filed: December 12, 1995
    Date of Patent: September 22, 1998
    Assignee: Owens Corning Fiberglas Technology Inc.
    Inventor: Jianzhong Huang
  • Patent number: 5798678
    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: July 1, 1996
    Date of Patent: August 25, 1998
    Assignee: American Superconductor Corporation
    Inventors: Michael D. Manlief, Gilbert N. Riley, Jr., John Voccio, Anthony J. Rodenbush
  • 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: 5731271
    Abstract: A method for growing a superconductive film, comprising:(a) helically winding a tape substrate around the outer periphery of a cylindrical or columnar holder and(b) growing a superconductive film on the surface of the tape substrate by plasma flash evaporation, while rotating the holder. According to the present invention, the heat contact between the holder and the tape substrate is stabilized and a high performance tape conductor can be obtained. In addition, degradation of superconductive performance possibly experienced, when the tape is used for a transmission cable or the like, can be lessened. Furthermore, the large area growth, which is the characteristic feature of plasma flash evaporation, is effectively utilized and production efficiency of a long tape conductor can be enhanced.
    Type: Grant
    Filed: September 25, 1996
    Date of Patent: March 24, 1998
    Assignees: Mitsubishi Cable Industries, Ltd., Hokkaido Electric Power Company, Inc., International Superconductivity Technology Center
    Inventors: Shigenori Yuhya, Jiro Tsujino, Noriyuki Tatsumi, Yoh Shiohara
  • Patent number: 5719106
    Abstract: A holder (1) provided with a spirally extending groove (2) is prepared and an oxide superconducting wire (3) is arranged in the groove (2) to be heat treated, so that each portion thereof is not bonded to another portion during the heat treatment.
    Type: Grant
    Filed: February 28, 1994
    Date of Patent: February 17, 1998
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Hidehito Mukai, Nobuhiro Shibuta
  • 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: 5716909
    Abstract: Process for increasing the pinning force of superconducting Bi-Sr-Ca-Cu-O ceramic moldings, which comprises heating the pure-phase 2212 phase of a Bi-Sr-Ca-Cu-O ceramic molding under pure oxygen or an oxygen-containing gas for from 1 to 40 minutes to a temperature of from 825.degree. to 900.degree. C. and generating secondary-phase precipitates in the process.
    Type: Grant
    Filed: October 1, 1996
    Date of Patent: February 10, 1998
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Peter Majewski, Guenter Petzow, Fritz Aldinger, Bernhard Hettich, Steffen Elschner
  • Patent number: 5672569
    Abstract: A superconducting circuit having patterned superconducting wiring lines. Each wiring line consists of at least one portion (2') of the thin film (2) of an oxide superconductor deposited on a substrate (1). The portion (2') has a predetermined crystal orientation and the remaining portions (2") have a different crystal orientation or changed to non-superconductor. The superconducting circuit has a planar surface.In variations, two different wiring lines (21, 22) each having a different crystal orientation are produced at different portions of a thin film of oxide superconductor, so that superconducting current flow separately through two different portions in a common thin film.
    Type: Grant
    Filed: March 8, 1995
    Date of Patent: September 30, 1997
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takao Nakamura, Hiroshi Inada, Michitomo Iiyama
  • Patent number: 5670434
    Abstract: Process for preparing a high-T.sub.c superconductor as a precursor material for the oxide-powder-in-tube method (OPIT). The present invention relates to a process for preparing a high-T.sub.c superconductor as a precursor material for the oxide-powder-in-tube method, which involves mixing the oxides of the elements Bi, Sr, Ca and Cu and completely melting them at temperatures of >1000.degree. C., then casting the melt onto a substrate which is kept at room temperature, and disintegrating the cooled melt block and grinding it into a powder.
    Type: Grant
    Filed: January 30, 1996
    Date of Patent: September 23, 1997
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Marc Neubacher, Joachim Bock, Christoph Lang, Eberhard Preisler, Helga Weis
  • Patent number: 5663120
    Abstract: In order to prevent expansion of a metal sheath which is heat treated in order to form an oxide high-temperature superconductor therein, the heat treatment temperature is held at a certain level in an intermediate stage of temperature rising in a step of heat treating the metal sheath after filling raw material for an oxide high-temperature superconductor into the metal sheath. After the heat treatment temperature is thus held at the certain level, the metal sheath is again heated to a target temperature. Preferably, the heat treatment temperature is held at a level which is selected in a range of at least 500.degree. C. and not more than 750.degree. C.
    Type: Grant
    Filed: September 29, 1994
    Date of Patent: September 2, 1997
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takeshi Hikata, Kenichi Sato
  • Patent number: 5663528
    Abstract: A clad superconductive wire or tape of an oxide superconductive material and a silver-copper alloy base containing 0.05-90 atomic % copper or a silver alloy. The silver-copper alloy base contains one or more elements selected from the group of Zr, Hf, Al, V, Nb and Ta in amounts of from 0.01-3 atomic %, or contains Au in amounts of 0.01-10 atomic %. The silver alloy contains one or more elements selected from the group of Ti, Zr, Hf, V, Nb, Ta, Mg, Ca, Sr and Ba in amounts of from 0.01 to 3 atomic %, or one or more elements selected from the group of Au, Al, Ga, In and Sn in amounts of 0.05 to 5 atomic %. The base material is filled with a Bi-containing oxide of Bi.sub.1 Pb.sub.u Sr.sub.x Ca.sub.y Cu.sub.z O.sub.w wherein u=0-0.3, X=0.8-1.2, y=0.2-1.2, and z=0.8-2.0, and processed to obtain a superconductive wire or tape having enhanced mechanical strength, superconductivity and plastic workability.
    Type: Grant
    Filed: December 21, 1993
    Date of Patent: September 2, 1997
    Assignees: Sumitomo Heavy Industries, Ltd., National Research Institute for Metals
    Inventors: Yoshiaki Tanaka, Tomoyuki Yanagiya, Fumiaki Matsumoto, Masao Fukutomi, Toshihisa Asano, Kazunori Komori, Hiroshi Maeda
  • Patent number: 5648319
    Abstract: Disclosed is an oxide superconductor comprising an oxide of RE, Ba and Cu, which consists of a superconductor having a texture wherein the crystal directions of the 123 phase in the matrix are uniform, large angle grain boundaries having an directional difference larger than 20.degree. are not present and the 211 phase is finely dispersed, or an aggregate thereof, wherein the superconductor is formed into a plate or wire and the c-axis of the crystal of the formed body is uniform within .+-.30.degree. to the normal of the plate face of the formed body or in the range of from 60.degree. to 120.degree. to said normal. Also disclosed is a process for the preparation of an oxide superconductor as set forth above, which comprises inserting a formed body as mentioned above to a heating furnace and moving a region of a temperature at which grains are formed in the 123 phase of the matrix of the formed body, i.e., through a region having a temperature of from 1050.degree. to 910.degree. C.
    Type: Grant
    Filed: June 29, 1995
    Date of Patent: July 15, 1997
    Assignee: Nippon Steel Corporation
    Inventors: Mitsuru Morita, Katsuyoshi Miyamoto, Kiyoshi Sawano, Shouichi Matsuda
  • 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: 5646096
    Abstract: Patterned superconducting wiring lines each consisting of a portion of a thin film of an oxide superconductor deposited on a flat substrate, the portion having a predetermined crystal orientation (a-axis or c-axis orientation) with respect to a flat surface of the substrate, remaining portions of the thin film of the oxide superconductor having a different crystal orientation (c-axis or a-axis orientation) from the portion and/or consisting of an insulation zones. Both of the portion and the remaining portions have a substantially identical thickness so that the thin film has a substantially flat planar surface.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: July 8, 1997
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Hiroshi Inada, Takao Nakamura, Mitchimoto Iiyama
  • Patent number: 5583094
    Abstract: A tubular metal pipe and a solidified melt of a precursor of oxide superconducting material which is placed in contact with the metal pipe are subjected to heat treatment in an oxidizing atmosphere and at a temperature above the partial fusion temperature of the solidified melt to oxidize the metal pipe from its inside and outside and, as the oxidation proceeds, a melt of the solidified melt is effused through the tubular metal oxide layer to form a superconducting layer on its surface. This makes it possible to easily obtain a hollow oxide superconductor wherein a superconducting material layer is formed outside the metal oxide layer.
    Type: Grant
    Filed: September 28, 1994
    Date of Patent: December 10, 1996
    Assignees: Chubu Electric Power Company, Inc., Yoshihiro Abe, Showa Electric Wire & Cable Co., Ltd.
    Inventors: Yoshihiro Abe, Toshihiro Kasuga, Koichi Nakamura, Eikichi Inukai
  • Patent number: 5554585
    Abstract: A lanthanum aluminate (LaAlO.sub.3) substrate on which thin films of layered perovskite copper oxide superconductors are formed. Lanthanum aluminate, with a pseudo-cubic perovskite crystal structure, has a crystal structure and lattice constant that closely match the crystal structures and lattice constants of the layered perovskite superconductors. Therefore, it promotes epitaxial film growth of the superconductors, with the crystals being oriented in the proper direction for good superconductive electrical properties, such as a high critical current density. In addition, LaAlO.sub.3 has good high frequency properties, such as a low loss tangent and low dielectric constant at superconductive temperatures. Finally, lanthanum aluminate does not significantly interact with the superconductors. Lanthanum aluminate can also be used to form thin insulating films between the superconductor layers, which allows for the fabrication of a wide variety of superconductor circuit elements.
    Type: Grant
    Filed: November 4, 1994
    Date of Patent: September 10, 1996
    Assignee: TRW Inc.
    Inventors: Randy W. Simon, Christine E. Platt, Alfred E. Lee, Gregory S. Lee
  • 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: 5550103
    Abstract: A method of producing a high temperature long length coil of superconductor wire or tape having improved critical current densities by utilizing an in-line pressing operation to heal the microcracks in the tape or wire which were introduced in rolling and coiling operations. The material can be Bismuth-2223, Bismuth 2212, Thallium-1234 or any other high temperature superconducting material. In the case of the Bismuth-2223, an improved "powder-in-tube" processing operation is provided to utilize excess bismuth, calcium, and copper in the initial composition material, and forming a partially developed Bi-2223 phase in the precursor powder introduced into the silver tubes. The final product has a 90-100% Bi-2223 phase with fine dispersions of secondary phases, to provide improved flux pinning thereby improving the critical current density of the material.
    Type: Grant
    Filed: August 18, 1993
    Date of Patent: August 27, 1996
    Assignee: IGC/Advanced Superconductors, Inc.
    Inventors: Leszek Motowidlo, Pradeep Haldar
  • Patent number: 5545613
    Abstract: A method of preparing a superconducting oxide by combining the metallic elements of the oxide to form an alloy, followed by oxidation of the alloy to form the oxide. Superconducting oxide-metal composites are prepared in which a noble metal phase intimately mixed with the oxide phase results in improved mechanical properties. The superconducting oxides and oxide-metal composites are provided in a variety of useful forms.
    Type: Grant
    Filed: July 11, 1994
    Date of Patent: August 13, 1996
    Assignee: Massachusetts Institute of Technology
    Inventors: Gregory J. Yurek, John B. VanderSande
  • Patent number: 5538942
    Abstract: A superconducting magnet coil is produced by winding a superconducting wire to form a coil; impregnating the coil with a curable resin composition of low viscosity which contains for example at least one epoxy resin selected from the group consisting of diglycidyl ether of bisphenol A, diglycidyl ether of bisphenol F and diglycidyl ether of bisphenol AF, all having a number-average molecular weight of 350-1,000, a flexibilizer and a curing catalyst, to obtain a curable-resin composition-impregnated coil; and heating the curable-resin-composition-impregnated coil to cure the composition.
    Type: Grant
    Filed: January 20, 1995
    Date of Patent: July 23, 1996
    Assignee: Hitachi, Ltd.
    Inventors: Toru Koyama, Koo Honjo, Masao Suzuki, Akio Takahashi, Akio Mukoh, Keiji Fukushi, Seiji Numata
  • Patent number: 5525585
    Abstract: The present invention provides a process for the preparation of YBa.sub.2 Cu.sub.3 O.sub.7-x superconductor which comprises surrounding a sintered material in which the molar ratio of Y:Ba:Cu is 2:1:1 with liquid-forming powder and subjecting the powder compact to isothermal heat-treatment at a temperature below the peritectic temperature of YBa.sub.2 Cu.sub.3 O.sub.7-x. The YBa.sub.2 Cu.sub.3 O.sub.7-x superconductors prepared according to the present invention have aligned grain structure in one direction and thus exhibit a high critical current density.
    Type: Grant
    Filed: June 16, 1994
    Date of Patent: June 11, 1996
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Jeong-Hun Suh, Young A. Jee, Suk-Joong L. Kang, Duk Y. Yoon
  • 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: 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: 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: 5459124
    Abstract: A process for producing an oxide superconductor, comprising putting a formed body of raw material powders for forming an oxide superconductor on silver or silver oxide within a pan which does not melt at the melting point of silver, heating the pan to a temperature higher than the melting point of silver to bring the formed body to a semi-molten state with the formed body being floated on molten silver, cooling the pan and taking the formed body out of the re-solidified silver. This process enables a large bulk material having a diameter of 10 cm or more to be produced without occurrence of cracking.
    Type: Grant
    Filed: October 29, 1993
    Date of Patent: October 17, 1995
    Assignees: International Superconductivity Technology Center, Shinkoku Electric Power Co., Inc., Nippon Steel Corporation
    Inventors: Terutsugu Oyama, Masato Murakami, Naoki Koshizuka, Shoji Tanaka
  • Patent number: 5439880
    Abstract: A method of preparing a superconducting oxide by combining the metallic elements of the oxide to form an alloy, followed by oxidation of the alloy to form the oxide. Superconducting oxide-metal composites are prepared in which a noble metal phase intimately mixed with the oxide phase results in improved mechanical properties. The superconducting oxides and oxide-metal composites are provided in a variety of useful forms.
    Type: Grant
    Filed: May 3, 1993
    Date of Patent: August 8, 1995
    Assignee: Massachusetts Institute of Technology
    Inventors: Gregory J. Yurek, John B. Vander Sande
  • 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: 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: 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: 5413753
    Abstract: Methods of forming composite articles of superconducting materials and metal at ambient temperature by applying a mixture of metal and binder to a ceramic oxide preform to yield a coated preform which is then heat treated to provide composite articles of superconducting ceramic and metal.
    Type: Grant
    Filed: September 17, 1993
    Date of Patent: May 9, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventor: George E. Zahr
  • Patent number: 5411938
    Abstract: A method and article of manufacture of a lead oxide based glass coating on a high temperature superconductor. The method includes preparing a dispersion of glass powders in a solution, applying the dispersion to the superconductor, drying the dispersion before applying another coating and heating the glass powder dispersion at temperatures below oxygen diffusion onset and above the glass melting point to form a continuous glass coating on the superconductor to establish compressive stresses which enhance the fracture strength of the superconductor.
    Type: Grant
    Filed: July 30, 1993
    Date of Patent: May 2, 1995
    Assignee: University of Chicago
    Inventors: Weite Wu, Cha Y. Chu, Kenneth C. Goretta, Jules L. Routbort
  • Patent number: 5403818
    Abstract: A Bi--Sr--Ca--Cu--O ceramic superconductor contains 0112 phases which are finely dispersed in a 2212-phase matrix with its c-axis oriented perpendicular to a growth direction.A method of preparing a Bi--Sr--Ca--Cu--O ceramic superconductor comprises the steps of growing crystals under conditions satisfying:G/R.gtoreq.1 and G.R.gtoreq.10000where G (K/cm) represents the temperature gradient at a solid-liquid interface and R (mm/h) represents the rate of crystal growth, and annealing the grown crystals in an atmosphere having oxygen partial pressure of at least 0.05 atm. within a temperature-range of 800.degree. to 860.degree. C. for at least 2 hours.
    Type: Grant
    Filed: March 19, 1993
    Date of Patent: April 4, 1995
    Assignee: Engineering Research Association For Superconductive Generation Equipment and Materials
    Inventor: Kazuhiko Hayashi
  • 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: 5399547
    Abstract: The present invention provides a methodology for increasing the critical current density carried by high transition temperature; superconductive materials. The methodology is employed using any Noble metal to form an electrically conductive coating; and is used with any high transition temperature superconductive material conventionally known. The resulting improved superconducting material demonstrates an enhanced critical current density capability in the order of 48%; and substantially decreases the degradation of the critical current density in the presence of an applied magnetic field; and offers a range of other advantages including environmental degradation protection, an increased mechanical strength, and an improved capability for adding electrical contacts.
    Type: Grant
    Filed: September 17, 1993
    Date of Patent: March 21, 1995
    Assignee: Trustees of Boston University
    Inventors: Yehia Z. Negm, George O. Zimmerman, Robert E. Powers, Jr.
  • Patent number: 5399312
    Abstract: A process for fabricating Thallium-based superconducting tapes comprising the steps of: (1) preparing a powder mixture having a nominal composition of (Tl.sub.1-x-y Bi.sub.y Pb.sub.z)(Ba.sub.2-z Sr.sub.z)Ca.sub.2 Cu.sub.3 O.sub.9 ; (2) placing the powder mixture into a silver tube and drawing and/or swaging the silver tube containing the powder mixture into a wire having a pre-determined diameter, wherein x and y are real numbers between 0.2 and 0.4, and z is a real number between 0 and 2; (3) rolling the wire into a tape having a pre-determined thickness; and (4) subjecting the tape to a two-stage single-sintering process at two respective sintering temperatures. The two-stage single-sintering process of the present invention allows Thallium-based superconducting tapes to be fabricated which exhibit substantially increased critical current density, without causing a substantially increased cost and complexity, as do other prior art processes, such as the double-sintering process.
    Type: Grant
    Filed: October 4, 1993
    Date of Patent: March 21, 1995
    Assignee: Industrial Technology Research Institute
    Inventors: Ru-Shi Liu, Sheng-Feng Wu, Chung-Ho Tai, Der-Shiuh Shy
  • Patent number: 5384307
    Abstract: A method of forming the superconducting body comprises forming a body comprised of a precursor deposit of an oxide superconductor on a substrate formed from a silver alloy comprised of a solute metal from the group consisting of yttrium, aluminum, lithium, zirconium, alkaline earths, lanthanides, and mixtures thereof in an effective amount to form oxide particles that increase the hardness of the substrate, and the balance silver. The body is annealed in an oxidizing atmosphere to form the oxide particles in the substrate, and the deposit into a continuous oxide superconductor.
    Type: Grant
    Filed: January 18, 1994
    Date of Patent: January 24, 1995
    Assignee: General Electric Company
    Inventor: Kenneth W. Lay
  • Patent number: 5378684
    Abstract: In order to prevent expansion of a metal sheath which is heat treated in order to form an oxide high-temperature superconductor therein, the heat treatment temperature is held at a certain level in an intermediate stage of temperature rising in a step of heat treating the metal sheath after filling raw material for an oxide high-temperature superconductor into the metal sheath. After the heat treatment temperature is thus held at the certain level, the metal sheath is again heated to a target temperature. Preferably, the heat treatment temperature is held at a level which is selected in a range of at least 500.degree. C. and not more than 750.degree. C.
    Type: Grant
    Filed: September 10, 1991
    Date of Patent: January 3, 1995
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takeshi Hikata, Kenichi Sato
  • Patent number: 5374612
    Abstract: A superconductor wire comprising an inner core and an outer ring covering the core, wherein one of the inner core and the outer ring comprises a sintered silver powder and the other of the inner core and the outer ring on the core comprises a sintered oxide superconductor powder.
    Type: Grant
    Filed: December 31, 1992
    Date of Patent: December 20, 1994
    Assignee: Aisin Seiki Kabushiki Kaisha
    Inventors: Yoshitaka Ito, Masami Ishii, Tetsuo Oka, Takeo Nakagawa, Lihong Zhang
  • Patent number: 5372089
    Abstract: Disclosed herein is a method of forming a single-crystalline thin film having excellent crystallinity on a base material without depending on the material for and crystallinity of the base material. In this method, a base material is provided thereon with a mask which can prevent chemical species contained in a vapor phase from adhering to the base material. The base material is continuously moved along arrow A, to deliver a portion covered with the mask into the vapor phase for crystal growth. Thus, a thin film is successively deposited on the portion of the base material, which is delivered from under the mask, from the vapor phase. A crystal growth end is formed on a boundary region between a portion of the base material which is covered with the mask and that which is exposed to the vapor phase, so that a crystal having the same orientation as the growth end is grown on a portion of the base material newly exposed by the movement.
    Type: Grant
    Filed: July 26, 1993
    Date of Patent: December 13, 1994
    Assignees: Sumitomo Electric Industries, Ltd., The Tokyo Electric Power Company Incorporated
    Inventors: Noriyuki Yoshida, Satoshi Takano, Kousou Fujino, Shigeru Okuda, Tsukushi Hara, Hideo Ishii
  • Patent number: 5369087
    Abstract: A melt-texturing method for producing high transition temperature superconducting ceramic elements of given length, such as wires of Y Ba.sub.2 Cu.sub.3 O.sub.7-.delta., which method is much faster and efficient than the existing ones. In this method, an element made of grains of superconducting ceramic precursor material is subjected to zone melting at a number of different locations equally spaced apart along its length. This multi-zone-melting is carried out at the same time, under the same temperature and speed conditions and in the same direction so as to form a same number of similarly textured zones along the length of the element, which zones grow up while the method progresses until they merge. This method makes it possible to multiply the present rate of production known to be very low, by a number of the same order of magnitude as the number of different locations where zone melting is carried out.
    Type: Grant
    Filed: July 11, 1991
    Date of Patent: November 29, 1994
    Assignee: Noranda Inc.
    Inventors: Philip R. Critchlow, Julian Cave
  • Patent number: 5369089
    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: September 27, 1993
    Date of Patent: November 29, 1994
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kenichi Sato, Hidehito Mukai, Takeshi Hikata
  • Patent number: 5369088
    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: March 19, 1992
    Date of Patent: November 29, 1994
    Assignee: Sumitomo Electric Industries, Inc.
    Inventors: Hidehito Mukai, Kenichi Sato, Nobuhiro Shibuta
  • Patent number: 5356871
    Abstract: A method of making a high critical temperature superconductive fiber by fiber drawing a material of the family Bi.sub.x Pb.sub.y Sr.sub.2 Ca.sub.2 Cu.sub.3 O.sub.z where 1.9.ltoreq. x+y.ltoreq. 2.3. In the method a preform is made, fiber drawing is performed, and the resulting fiber is annealed in air, wherein said preform is constituted by a block of vitreous material having the formula Bi.sub.x P.sub.y Sr.sub.2 Ca.sub.2 Cu.sub.3 O.sub.z where: 1.9.ltoreq. x+y.ltoreq. 2.3 and a tube surrounding said block and made of a vitreous material having the formula Bi.sub.x' Sr.sub.2 Ca.sub.1 Cu.sub.2 O.sub.z' with 1.5.ltoreq. x'.ltoreq. 2.2.
    Type: Grant
    Filed: June 9, 1992
    Date of Patent: October 18, 1994
    Assignee: Alcatel Alsthom Compagnie General d'Electricite
    Inventors: Jean-Claude Bobo, Alain Wicker
  • Patent number: 5356869
    Abstract: Powder of a ceramic superconducting material is synthesized such that each particle of the powder is a single crystal having a flake-like, nonsymmetric morphology such that the c-axis is aligned parallel to the short dimension of the flake. Nonflake powder is synthesized by the normal methods and is pressed into pellets or other shapes and fired for excessive times to produce a coarse grained structure. The fired products are then crushed and ground producing the flake-like powder particles which exhibit superconducting characteristics when aligned with the crystal lattice.
    Type: Grant
    Filed: December 17, 1990
    Date of Patent: October 18, 1994
    Assignee: Arch Development Corporation
    Inventors: Donald W. Capone, Joseph Dusek
  • Patent number: 5318948
    Abstract: A high-temperature oxide superconductor is provided and comprises oxide crystals oriented in a certain direction, the oxide superconductor being substantially free of or containing a controlled amount of foreign phases, a non-superconducting phase and weak superconducting phase which are harmful for superconducting characteristics in the grains of the crystals and at the grain boundaries between the crystals. The foreign phases, if any, are finely and uniformly dispersed in the grains of the oxide crystals and at the grain boundaries. A wire made from the oxide superconductor, a coil from the wire, and a magnetic field generator from the coil are disclosed, the superconductor wire having only a single layer of oxide crystal grains in the thickness direction.
    Type: Grant
    Filed: April 13, 1992
    Date of Patent: June 7, 1994
    Assignee: Hitachi, Ltd.
    Inventors: Michiya Okada, Ryou Nishiwaki, Yoshihide Wadayama, Toshimi Matsumoto, Katsuzo Aihara, Tomoichi Kamo, Shinpei Matsuda, Toshihide Nabatame, Yukio Saito, Toyotaka Yuasa
  • Patent number: 5314867
    Abstract: A process of making high temperature Tl-based superconductors. The process includes the steps of reacting solid Ba--Ca--Cu-oxides with Tl.sub.2 O.sub.3 vapor. The process allows high quality Tl-based superconductors to be easily fabricated.
    Type: Grant
    Filed: July 25, 1991
    Date of Patent: May 24, 1994
    Assignee: University of Arkansas
    Inventors: Allen M. Hermann, Zhengzhi Sheng
  • Patent number: 5310704
    Abstract: A method of manufacturing a superconductive conductor containing a superconductive ceramic material generally expressed by the composition AaBbCc, where A represents at least a sort of element selected from a group of those belonging to the groups Ia, IIa and IIIb of the periodic table, B represent at least a single element selected from a group consisting of groups Ib, IIb and IIIa of the periodic table, C represents at least a single sort of element selected from a group of oxygen, carbon, nitrogen, fluorine and sulfur and a, b and c represent numbers showing composition ratios of A, B and C respectively, includes a step of melting a material generally expressed by a formula AaBb, a step of continuously drawing out a melt of AaBb from a hole provided in a frame, a step of solidifying the AaBb melt drawn out from the hole and a step of heating a solidified body of AaBb in an atmosphere containing C.
    Type: Grant
    Filed: March 6, 1992
    Date of Patent: May 10, 1994
    Assignee: Sumitomo Electric Industries, Inc.
    Inventors: Hajime Hitotsuyanagi, Kazuo Sawada, Kengo Ohkura, Yoshihiro Nakai, Kazuhiko Hayashi