With Zone Melting, Zone Solidification, Or Seed Pulling Patents (Class 505/451)
  • Patent number: 7964532
    Abstract: An RE123-based oxide superconductor characterized by comprising a conductive layer containing an REBa2Cu3O7-?-based oxide superconductor formed using a mixed material of at least RE2BaO4 and a Bax—Cuy—Oz-based material and a holding member which holds said conductive layer, where, RE is one type or more of elements selected from La, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Lu, and Y.
    Type: Grant
    Filed: March 31, 2006
    Date of Patent: June 21, 2011
    Assignee: International Superconductivity Technology Center, The Juridical Foundation
    Inventors: Shoji Tanaka, Naomichi Sakai, Takato Machi, Muralidhar Miryala
  • Patent number: 7608565
    Abstract: The invention provides a method of manufacturing a doped i X—Ba—Cu—O material, the method comprising the steps of: a) mixing an X—Ba—L—O or X—Ba—Cu—L—O material with an X—1 Ba—Cu—O material; and b) crystallising the mixture; 1 wherein each X is independently selected from a rare earth (Group IIIB) element, yttrium, a combination of rare earth elements, or a combination of yttrium and a rare earth element; and L is selected from U, Nb, Ta, Mo, W, Zr, Hf, Ag, Pt, Ru and Sn. The invention further provides a doped material manufactured by the method of the invention.
    Type: Grant
    Filed: June 7, 2004
    Date of Patent: October 27, 2009
    Inventors: Colin David Tarrant, Kelvin Robert Schneider, David Anthony Cardwell, Nadendla Hari Babu
  • Patent number: 7220706
    Abstract: A method for the enhanced melt-textured growth of superconducting crystals is disclosed for a sample having a first material capable of exhibiting superconducting properties. The sample is heated above a peritectic temperature of the first material, cooled below the peritectic temperature, and is subsequently subjected to a plurality of temperature spikes in which the sample is rapidly reheated above the peritectic temperature and recooled below the peritectic temperature to produce a superconducting crystalline structure substantially free of secondary nucleations. The resulting crystal is a superconducting crystalline structure comprising a plurality of bands formed in succession around a seed material. Each band has a non-uniform microstructure from an inner portion to an outer portion of the band.
    Type: Grant
    Filed: May 14, 2003
    Date of Patent: May 22, 2007
    Assignee: Praxair S.T. Technology, Inc.
    Inventor: Scott H. Streett
  • Patent number: 6627582
    Abstract: A large superconductor intermediate of REBa2Cu3Ox system (where RE is one kind or a combination of rare earth elements including Y), characterized by a structure that oxide superconductors having non-superconductive phases finely dispersed in REBa2Cu3Ox phases (123 phases) of different peritectic temperatures (Tp) are laminated three-dimensionally in the order of Tp's, seed crystals mounted on the oxide superconductor layer having a highest Tp, and excluded phases included in at least the oxide superconductor having the high Tp.
    Type: Grant
    Filed: March 8, 2001
    Date of Patent: September 30, 2003
    Assignee: Nippon Steel Corporation
    Inventors: Mitsuru Sawamura, Mitsuru Morita
  • Publication number: 20010053748
    Abstract: A large superconductor intermediate of REBa2Cu3Ox system (where RE is one kind or a combination of rare earth elements including Y), characterized by a structure that oxide superconductors having non-superconductive phases finely dispersed in REBa2Cu3Ox phases (123 phases) of different peritectic temperatures (Tp) are laminated three-dimensionally in the order of Tp's, seed crystals mounted on the oxide superconductor layer having a highest Tp, and excluded phases included in at least the oxide superconductor having the high Tp.
    Type: Application
    Filed: March 8, 2001
    Publication date: December 20, 2001
    Inventors: Mitsuru Sawamura, Mitsuru Morita
  • Patent number: 6326334
    Abstract: A lanthanum aluminate (LaAlO3) 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, LaAlO3 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 21, 1994
    Date of Patent: December 4, 2001
    Assignee: TRW Inc.
    Inventors: Randy Wayne Simon, Christine Elizabeth Platt, Alfred Euinam Lee, Gregory Steven Lee
  • Patent number: 6284712
    Abstract: A method for preparing a BSCCO-2223 oxide superconducting article includes annealing an oxide superconductor article comprised of BSCCO-2223 oxide superconductor at a temperature selected from the range of about 500° C.≦T≦787° C. and an annealing atmosphere having an oxygen pressure selected from within the region having a lower bound defined by the equation, PO2(lower)≧3.5×1010exp(−32,000/T+273) and an upper bound defined by the equation, PO2(upper)≦1.1×1012exp(−32,000/T+273). The article is annealed for a time sufficient to provide at least a 10% increase in critical current density as compared to the critical current density of the pre-anneal oxide superconductor article. An oxide superconductor having the formula Bi2−yPbySr2Ca2Cu3O10+x, where 0≦x≦1.5 and where 0≦y≦0.6 is obtained, the oxide superconductor characterized by a critical transition temperature of greater than 111.0 K, as determined by four point probe method.
    Type: Grant
    Filed: November 30, 1999
    Date of Patent: September 4, 2001
    Inventors: Alexander Otto, Gilbert N. Riley, Jr., William L. Carter
  • Publication number: 20010007849
    Abstract: A method of producing a composite material of a bismuth 2212 phase and a metallic substrate, wherein the first and second baking are conducted as an isothermal heat treatment.
    Type: Application
    Filed: January 22, 2001
    Publication date: July 12, 2001
    Inventors: Hitoshi Kitaguchi, Hirohaki Kumakura, Kazumasa Togano
  • Patent number: 6255255
    Abstract: An oxide superconducting material includes a REBa2Cu3O7−x phase (RE designating one or a combination of two or more rare earth elements including Y), particles composed of Ce, Ba, Cu and O dispersed therein, and RE2BaCuO5 or RE4Ba2Cu2O10 dispersed therein. A method is provided for producing the superconducting material from a mixed powder obtained by adding a Ce—Ba—Cu—O system additive to a starting material powder containing RE, Ba, Cu and O.
    Type: Grant
    Filed: November 29, 1999
    Date of Patent: July 3, 2001
    Assignee: Nippon Steel Corporation
    Inventors: Mitsuru Morita, Tetsuro Nose
  • Patent number: 6136756
    Abstract: The high temperature superconducting material is made from a base material having two opposing surfaces and including a high purity yttrium barium copper oxide compound having a YBa.sub.2 Cu.sub.3 O.sub.7-x (123) composition with silver oxide. The method of making the superconducting material includes controlling a temperature of each opposing surface of the base material to form a time-dependent spatial temperature gradient across the base material; measuring the time-dependent spatial temperature gradient, determining whether it is within a desired range and controlling it so that the time-dependent spatial temperature gradient remains within the desired range, thereby melt-texturing the base material while decomposing the silver oxide into silver and transforming the base material into quasi-crystalline superconducting regions having YBa.sub.2 Cu.sub.3 O.sub.7-x (123) composition, intrinsically non-superconducting material zones consisting of coherent yttrium-rich material having a Y.sub.2 BaCuO.sub.
    Type: Grant
    Filed: June 23, 1995
    Date of Patent: October 24, 2000
    Assignee: Adelwitz Technologiezentrum GmbH
    Inventors: Gerhard Langbein, Frank Werfel
  • Patent number: 6121205
    Abstract: A bulk superconductor including a plurality of units each composed of a substrate and a superconductive layer of R--Ba--Cu--O, where R is selected from La, Nd, Sm, Eu, Gd, Y, Dy, Ho, Er, Tm, Yb and mixtures thereof, formed on the substrate. The units are arranged in a row or in a matrix such that the superconductive layers of respective units are superconductively joined with each other.
    Type: Grant
    Filed: May 13, 1997
    Date of Patent: September 19, 2000
    Assignees: International Superconductivity Technology Center, Railway Technical Research Institute
    Inventors: Masato Murakami, Kazuhiko Sawada, Naomichi Sakai, Takamitsu Higuchi
  • Patent number: 6103670
    Abstract: An oxide superconductor which has high mechanical strength and exhibits favorable magnetic properties and high resistance to environment. Further, a method of manufacturing this oxide superconductor, namely, a method of manufacturing a RE--Ba--Cu--O oxide superconductor (RE is one or more kinds of rare earth elements including Y) by performing a treatment, which includes at least a burning process to be performed in a range of temperatures that are higher than the melting point of a raw material mixture containing a RE-compound raw material, a Ba-compound raw material and a Cu-compound raw material, on the aforesaid raw material mixture. This method further comprises the addition step of adding 1 to 30 in percent by weight (wt %) of Ag to the raw material mixture, and the crystallization step of melting the raw material mixture, to which Ag is added, at a temperature that is not lower than a temperature at which the raw material mixture is decomposed and fused into the RE.sub.2 BaCuO.sub.
    Type: Grant
    Filed: April 16, 1999
    Date of Patent: August 15, 2000
    Assignees: Dowa Mining Co., Ltd., Chubu Electric Power Co., Inc.
    Inventors: Shuichi Kohayashi, Shuetsu Haseyama, Shuji Yoshizawa, Shigeo Nagaya
  • Patent number: 6083886
    Abstract: Provided is a method of preparing a large-sized oxide superconducting bulk body having excellent characteristics and high homogeneity. The method is adapted to prepare an oxide superconducting bulk body by melt growth through a seed crystal method, and comprises steps of preparing a precursor by press-molding material powder obtained by mixing REBa.sub.2 Cu.sub.3 O.sub.7-z powder with RE.sub.2 BaCuO.sub.5 or RE.sub.4 Ba.sub.2 Cu.sub.2 O.sub.10 powder and a platinum additive, homogeneously semi-melting the precursor by holding the same at a holding temperature T.sub.1 .degree. C. (t.sub.1 +20.ltoreq.T.sub.1 .ltoreq.t.sub.1 +80 assuming that the melting point of the oxide superconducting bulk body is t.sub.1 .degree. C.) for a prescribed time, and crystal-growing the precursor at a temperature not more than the melting point t.sub.1 .degree. C.
    Type: Grant
    Filed: July 6, 1998
    Date of Patent: July 4, 2000
    Assignees: Sumitomo Electric Industries, Ltd., International Superconductivity Technology Center
    Inventors: Noriki Hayashi, Masato Murakami
  • Patent number: 6046139
    Abstract: We make large (in excess of 2 cm in diameter), single crystal YBa.sub.2 Cu.sub.3 O.sub.7-x [123 YBCO] crystals, where x.ltoreq.0.6, in a seventeen step process or some variant thereof from finely ground and well mixed 123 YBCO and 211 YBCO powders with a small amount of Pt by controlling the rate of cooling from within a compact of the powders using a temperature gradient in the radial and axial planes (independently) of about 1-1.degree. C./inch diameter of compact to nucleate the crystal growth. We promote crystal growth as well using a samarium oxide seed crystal, preferably SmBa.sub.2 Cu.sub.3 O.sub.(7-y), where y.ltoreq.1.6. After nucleation we cool the compact slowly at a rate from about 0.1-1.degree. C./hr to promote the single crystal development.
    Type: Grant
    Filed: August 7, 1998
    Date of Patent: April 4, 2000
    Assignee: The Boeing Company
    Inventors: Kay Y. Blohowiak, Darryl F. Garrigus, Thomas S. Luhman, Kevin E. McCrary, Michael Strasik, Ilhan Aksay, Fatih Dogan, William C. Hicks, Corrie B. Martin
  • Patent number: 6034036
    Abstract: The present invention is aimed to provide a means for manufacturing a RE123 system oxide superconductor showing good superconductivity characteristics under atmospheric ambiance.
    Type: Grant
    Filed: September 25, 1997
    Date of Patent: March 7, 2000
    Assignees: International Superconductivity Technology Center, Ishikawajima-Harima Jukogyo Kabushiki Kaisha
    Inventors: Minoru Tagami, Xin Yao, Makoto Kambara, Yuh Shiohara, Shoji Tanaka
  • Patent number: 6008162
    Abstract: The present invention can provide an oxide superconductive film with a smooth surface and at homogeneous thickness on a simple substrate structure at a high film formation rate. In a liquid phase epitaxial growth method for producing an ReBa.sub.2 Cu.sub.3 Ox film (3) (Rerepresents one selected from lanthanoids such as Y and Nd, and X represents the oxygen amount) having a 123 type crystal structure from a molten liquid (1), a substrate (2) surface is inclined by 1 degree to 44 degrees with respect to the molten liquid surface at the time of separating the film from the molten liquid after film formation. After separating the film from the molten liquid, the substrate is rotated at 300 rpm to 3000 rpm for 5 seconds to 5 minutes. The film formation atmosphere contains 2 at. % of oxygen and 98 at. % of nitrogen, and the film formation temperature is 900 to 970.degree. C.
    Type: Grant
    Filed: March 31, 1998
    Date of Patent: December 28, 1999
    Assignees: NEC Corporation, International Conductivity Technology Center
    Inventors: Sadahiko Miura, Tadataka Morishita, Youichi Enomoto
  • Patent number: 5968878
    Abstract: A high critical temperature and high critical current density superconductor containing a matrix phase of a metal oxide expressed by the formula RE.sup.1 Ba.sub.2 Cu.sub.3 O.sub.p wherein RE.sup.1 stands for La, Nd, Sm, Eu or Gd and p is a number of 6.8-7.2, a first dispersed phase of a metal oxide expressed by the formula RE.sup.2.sub.1+d Ba.sub.2-d Cu.sub.3 O.sub.q wherein RE.sup.2 stands for La, Nd, Sm, Eu or Gd, d is a number of 0<d<0.5 and q is a number of 6.0-7.2 and a second dispersed phase of a metal oxide expressed by the formula RE.sup.3.sub.4-2x Ba.sub.2+2x Cu.sub.2-x O.sub.10-y wherein RE stands for La or Nd, x is a number of 0<x .English Pound.0.25 and y is a number of 0<y<0.5. The first and second phases are dispersed in the matrix. The above superconductor may be prepared by cooling a partial melt having a temperature of 1,000.degree.-1,300.degree. C. and containing a major molar amount of RE.sup.1 Ba.sub.2 Cu.sub.3 O.sub.p and a minor molar amount of RE.sup.3.sub.4-2x Ba.sub.
    Type: Grant
    Filed: February 27, 1998
    Date of Patent: October 19, 1999
    Assignees: International Superconductivity Technology Center, Railway Technical Research Institute
    Inventors: Hiroki Kojo, Sang-Im Yoo, Masato Murakami
  • Patent number: 5962374
    Abstract: A process for preparing an oxide crystal by means of solution growth in the presence of a solvent is provided. The solvent includes a mixture of an oxide containing at least one member of those elements which constitute the oxide crystal, a halide containing at least one member of those elements which constitute the oxide crystal, and metallic silver.
    Type: Grant
    Filed: February 20, 1998
    Date of Patent: October 5, 1999
    Assignee: International Superconductivity Technology Center
    Inventors: Yuusuke Niiori, Yasuji Yamada, Junichi Kawashima, Izumi Hirabayashi
  • Patent number: 5958843
    Abstract: A bulk superconductor is produced by subjecting REBa.sub.2 Cu.sub.3 O.sub.y oxide to oxygen annealing after many holes have been formed in the oxide body.
    Type: Grant
    Filed: September 5, 1997
    Date of Patent: September 28, 1999
    Assignees: International Superconductivity Technology Center, Railway Technical Research Institute
    Inventors: Naomichi Sakai, Mikio Takahashi, Ken Nagashima, Masato Murakami
  • Patent number: 5958840
    Abstract: An oxide superconductor which has high mechanical strength and exhibits favorable magnetic properties and high resistance to environment. Further, a method of manufacturing this oxide superconductor, namely, a method of manufacturing a RE--Ba--Cu--O oxide superconductor (RE is one or more kinds of rare earth elements including Y) by performing a treatment, which includes at least a burning process to be performed in a range of temperatures that are higher than the melting point of a raw material mixture containing a RE-compound raw material, a Ba-compound raw material and a Cu-compound raw material, on the aforesaid raw material mixture. This method further comprises the addition step of adding 1 to 30 in percent by weight (wt %) of Ag to the raw material mixture, and the crystallization step of melting the raw material mixture, to which Ag is added, at a temperature that is not lower than a temperature at which the raw material mixture is decomposed and fused into the RE.sub.2 BaCuO.sub.
    Type: Grant
    Filed: July 30, 1997
    Date of Patent: September 28, 1999
    Assignees: Dowa Mining Co., Ltd., Chubu Electric Power Company, Incorporated
    Inventors: Shuichi Kohayashi, Shuetsu Haseyama, Shuji Yoshizawa, Shigeo Nagaya
  • Patent number: 5891828
    Abstract: PrBa.sub.2 Cu.sub.3 O.sub.Y exhibiting superconductivity is provided by a method including the steps of preparing a solvent consisting of a mixture of praseodymium oxide, at least one of barium oxide and barium carbonate, and copper oxide at a mixing ratio of between 1:3:5 and 1:8:20, disposing the solvent between a feed rod of PrBa.sub.2 Cu.sub.3 O.sub.7 formed to a high density and a seed crystal, heating the solvent to a temperature of 880.degree.-980.degree. C. in an atmosphere of an inert gas of at least one of argon and nitrogen mixed with 0.01-2% oxygen to form a floating solvent zone, moving the floating solvent zone toward the feed rod at 0.1-1.0 mm/hr under a temperature gradient at the solid-liquid interface of 25.degree.-35.degree. C./mm to precipitate single crystal on the seed crystal, and heat-treating the single crystal obtained in an atmosphere containing not less than 15% oxygen. Another aspect of the invention provides a superconducting device including the superconducting PrBa.sub.2 Cu.
    Type: Grant
    Filed: March 26, 1997
    Date of Patent: April 6, 1999
    Assignee: Agency of Industrial Science & Technology, Ministry of International Trade & Industry
    Inventors: Kunihiko Oka, Zhigang Zou, Toshimitsu Ito, Hiroshi Akoh
  • Patent number: 5869431
    Abstract: A method of fabricating bulk superconducting material such as RBa.sub.2 Cu.sub.3 O.sub.7-.delta. where R is La or Y comprising depositing a thin epitaxially oriented film of Nd or Sm (123) on an oxide substrate. The powder oxides of RBa.sub.2 Cu.sub.3 O.sub.7-.delta. or oxides and/or carbonates of R and Ba and Cu present in mole ratios to form RBa.sub.2 Cu.sub.3 O.sub.7-.delta., where R is Y or La are heated, in physical contact with the thin film of Nd or Sm (123) on the oxide substrate to a temperature sufficient to form a liquid phase in the oxide or carbonate mixture while maintaining the thin film solid to grow a large single domain 123 superconducting material. Then the material is cooled. The thin film is between 200 .ANG. and 2000 .ANG.. A construction prepared by the method is also disclosed.
    Type: Grant
    Filed: April 15, 1996
    Date of Patent: February 9, 1999
    Assignee: The University of Chicago
    Inventors: Boyd W. Veal, Arvydas Paulikas, Uthamalingam Balachandran, Wei Zhong
  • Patent number: 5851956
    Abstract: A large oxide crystal of high quality is manufactured by increasing the speed of crystal growth without affecting crystal growth. A melt of BaO--CuO as a raw material put in a crucible is heated and melt in the presence of a solid phase precipitate of Y.sub.2 BaCuO.sub.5 and kept at a prescribed temperature. Thereafter, a seed crystal is pulled up while being rotated, with the seed crystal being in contact with the surface of the melt, whereby an oxide crystal having the structure of YBa.sub.2 Cu.sub.3 O.sub.7-x this method, an atmosphere for growing the oxide crystal has an oxygen partial pressure higher than that in an ambient atmosphere.
    Type: Grant
    Filed: October 7, 1996
    Date of Patent: December 22, 1998
    Assignees: Sumitomo Electric Industries, Ltd., Ishikawajima-Harima Heavy Industries Co., Ltd., International Superconductivity Technology Center
    Inventors: Yasuo Namikawa, Xin Yao, Masahiro Egami, Yuh Shiohara
  • Patent number: 5849673
    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 7, 1994
    Date of Patent: December 15, 1998
    Assignee: TRW Inc.
    Inventors: Randy Wayne Simon, Christine Elizabeth Platt, Alfred Euinam Lee, Gregory Steven Lee
  • Patent number: 5830829
    Abstract: The invention relates to a process for producing textured high-temperature superconducting solid shaped parts, which comprises solid shaped parts made of oxide-ceramic superconducting material of a phase mixture of the substance class YBCO first being molded, pressed and sintered, a zonewise thermal treatment then being carried out along their longitudinal axis. Heating is first carried out, in a first zone, to a temperature in the range of from 50 to 200 K below the peritectic melting temperature of the phase mixture initially present in the shaped part, the temperature then is raised, in a second zone having a temperature gradient in the range of from 10 to 250 K/cm, then, in a third zone, a temperature of up to 50 K above the peritectic melting temperature of the phase mixture initially present in the shaped part is maintained, cooling then being carried out, in a fourth zone having a temperature gradient in the range of from 10 to 250 K/cm.
    Type: Grant
    Filed: November 27, 1995
    Date of Patent: November 3, 1998
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Markus Brand, Gunter Brommer, Steffen Elschner, Stephan Gauss, Wolf Assmus
  • Patent number: 5810984
    Abstract: A nitrogen oxide sensor and a method of manufacturing the sensor are disclosed. The sensor has a gas detecting portion including sensitive material having electric property thereof subject to change in association with presence of nitrogen oxide in gas and a pair of electrodes electrically connected with the gas detecting portion. The gas detecting portion includes, as a main component thereof, metal oxide compound represented by a general formula:Bi.sub.2 Sr.sub.2 (Ca.sub.1-x Y.sub.x)Cu.sub.2 O.sub.8+y(0.8.ltoreq.x.ltoreq.1; 0.ltoreq.y.ltoreq.1)and having the 2212 phase crystal structure and crystalline size greater than 100 .ANG..
    Type: Grant
    Filed: April 22, 1997
    Date of Patent: September 22, 1998
    Assignee: Osaka Gas Co., Ltd.
    Inventors: Shuzo Kudo, Hisao Ohnishi, Hisashi Sakai
  • Patent number: 5786304
    Abstract: A joining product of oxide superconducting materials having a high current density and process for producing the same. A joining product comprising a plurality of oxide superconducting materials having an identical crystal orientation joined with each other through a superconducting phase of the same type as described above which has the same crystal orientation as the oxide superconducting materials and a lower peritectic temperature than the oxide superconducting materials.
    Type: Grant
    Filed: September 30, 1994
    Date of Patent: July 28, 1998
    Assignee: Nippon Steel Corporation
    Inventors: Keiichi Kimura, Katuyoshi Miyamoto, Misao Hashimoto
  • Patent number: 5776864
    Abstract: A method of fabricating bulk YBa.sub.2 Cu.sub.3 O.sub.x where compressed powder oxides and/or carbonates of Y and Ba and Cu present in mole ratios to form YBa.sub.2 Cu.sub.3 O.sub.x are heated in the presence of a Nd.sub.1+x Ba.sub.2-x Cu.sub.3 O.sub.y seed crystal to a temperature sufficient to form a liquid phase in the YBa.sub.2 Cu.sub.3 O.sub.x while maintaining the seed crystal solid. The materials are slowly cooled to provide a YBa.sub.2 Cu.sub.3 O.sub.x material having a predetermined number of domains between 1 and 5. Crack-free single domain materials can be formed using either plate shaped seed crystals or cube shaped seed crystals with a pedestal of preferential orientation material.
    Type: Grant
    Filed: April 1, 1997
    Date of Patent: July 7, 1998
    Assignee: The University of Chicago
    Inventors: Volker Todt, Dean J. Miller, Donglu Shi, Suvankar Sengupta
  • Patent number: 5643857
    Abstract: A ceramic superconductive material (1) including a compound containing oxygen and at least two types of metal elements and having layer structure is molten in a vessel (2), at least an inner surface (3) of which is formed of a solid solution alloy having a base of gold or silver. Preferably the alloy is prepared from Au--5 to 40 wt. % Pd or Ag--5 to 40 wt. % Pd.
    Type: Grant
    Filed: May 8, 1991
    Date of Patent: July 1, 1997
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventor: Kazuhiko Hayashi
  • 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: 5627142
    Abstract: A composite material is disclosed which includes a substrate, an oriented film provided on a surface of the substrate and formed of a crystal of a Y123 metal oxide of the formula LnBa.sub.2 Cu.sub.3 O.sub.y wherein Ln stands for Y or an element belonging to the lanthanoid and y is a number of 6-7, and a layer of a Y123 metal oxide of the formula LnBa.sub.2 Cu.sub.3 O.sub.y wherein Ln stands for Y or an element belonging to the lanthanoid and y is a number of 6-7 formed on the oriented film.
    Type: Grant
    Filed: July 25, 1994
    Date of Patent: May 6, 1997
    Assignees: International Superconductivity Technology Center, Hitachi Cable, Ltd., Hokkaido Electric Power Co., Inc., Kyushu Electric Power Co., Inc., Kansai Electric Power Co., Inc., Fujikura, Ltd.
    Inventors: Yasuji Yamada, Masaru Nakamura, Noriyuki Tatsumi, Jiro Tsujino, Kanshi Ohtsu, Yasuo Kanamori, Minoru Tagami, Atsushi Kume, Yuh Shiohara, Shoji Tanaka
  • Patent number: 5602081
    Abstract: A method of preparing a crystal of a Y-series 123 metal oxide is disclosed, in which a substrate is immersed in a liquid phase which comprises components constituting the metal oxide. The liquid phase contains a solid phase located at a position different from the position at which the substrate contacts the liquid phase. The solid phase provides the liquid phase with solutes which constitute the Y-series 123 metal oxide so that the solutes are transported to the position at which the substrate and the liquid phase contact, thereby permitting the Y-series 123 metal oxide to grow on the substrate as primary crystals.
    Type: Grant
    Filed: May 9, 1994
    Date of Patent: February 11, 1997
    Assignees: International Superconductivity Technology Center, Mitsubishi Cable Industries
    Inventors: Masaru Nakamura, Yasuji Yamada, Minoru Tagami, Yuh Shiohara, Shoji Tanaka
  • Patent number: 5602080
    Abstract: This method for manufacturing lattice-matched substrates for high-T.sub.c superconductors employs at least two materials chosen from the group of known suitable substrate materials, of which one has a lattice constant smaller than the lattice constant(s) of the perovskite subcell of the selected superconductor material, while the other one has a lattice constant greater than the lattice constant of the perovskite subcell of the selected superconductor. These materials are then powdered and mixed intimately for providing a single-crystal either from the molten mixture of the chosen materials or by thin film deposition, said single-crystal containing appropriate molar percentages of the chosen materials so that resulting lattice constant is essentially the same as that of the selected superconductor material.
    Type: Grant
    Filed: February 9, 1994
    Date of Patent: February 11, 1997
    Assignee: International Business Machines Corporation
    Inventors: Johannes G. Bednorz, Jochen D. Mannhart, Carl A. Mueller, Darrell G. Schlom
  • 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: 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: 5536704
    Abstract: A composite material comprising a bulky substrate of a Y-series 123 metal oxide crystal, and at least one layer provided on a surface of the substrate and formed of a crystal of a Y-series 123 metal oxide. The substrate may be produced by immersing a seed material in a liquid phase which comprises components constituting the metal oxide. The liquid phase contains a solid phase located at a position different from the position at which the seed material contacts the liquid phase. The solid phase provides the liquid phase with solutes which constitute the Y-series 123 metal oxide so that the solutes are transported to the position at which the seed material and the liquid phase contact, thereby permitting the Y-series 123 metal oxide to grow on the seed material as primary crystals and to obtain the bulky substrate. The layer of a Y-series 123 metal oxide may be formed on the substrate by a sputtering method, a vacuum deposition method, a laser abrasion method, a CVD method or a liquid phase epitaxy method.
    Type: Grant
    Filed: May 9, 1994
    Date of Patent: July 16, 1996
    Assignees: International Superconductivity Technology Center, Mitsubishi Cable Industries, Ltd., Kyocera Corporation, Japan Energy Corporation
    Inventors: Yasuji Yamada, Minoru Tagami, Masaru Nakamura, Hideki Sakai, Koichi Uehara, Yuh Shiohara, Shoji Tanaka
  • Patent number: 5527767
    Abstract: There is disclosed a method for annealing oxide thin film superconductors having layered structures including at least Cu--O layers in which each oxide thin film superconductor is heated partially by a heating means and the heating portion is moved at a predetermined speed.
    Type: Grant
    Filed: May 5, 1994
    Date of Patent: June 18, 1996
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kentaro Setsune, Kiyotaka Wasa, You Ichikawa
  • 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: 5444040
    Abstract: A method of manufacturing a single crystal of a superconductive oxide by a travelling solvent floating zone method (TSFZ Method). In this manufacturing method, a sintered feed rod of an oxide belonging to a tetragonal system, exhibiting anisotropic properties and superconductive properties and having a stoichiometric composition of the superconductive oxide is melted into a layer of a solvent mainly consisting of a oxidized copper and arranged in an infrared heating furnace under an oxygen pressure thereby growing a large single crystal of the superconductive oxide which is 5 mm or over in diameter and 40 mm or over in length.The superconductive oxide is one selected from the group consisting of La.sub.2-x A.sub.x CuO.sub.4 (A:Sr,Ba), Nd.sub.2-x Ce.sub.x CuO.sub.4, YBa.sub.2 Cu.sub.3 O.sub.7-x, BiSrCaCu.sub.2 O.sub.x, Tl.sub.2 Ba.sub.2 Ca.sub.2 Cu.sub.3 O.sub.
    Type: Grant
    Filed: November 6, 1992
    Date of Patent: August 22, 1995
    Assignee: Seiko Epson Corporation
    Inventors: Hironao Kojima, Isao Tanaka
  • Patent number: 5413986
    Abstract: A method for producing a thin oxide superconducting film possessing high crystallinity and excellent quality and a novel single crystal as a substrate allowing easy formation of an epitaxial film of high quality usable for the method are provided. The method for the production of the thin oxide superconducting film is characterized by using as a substrate a single crystal of SrLaGaO.sub.4 which is a high-melting oxide and effecting epitaxial growth of a thin oxide superconducting film on the substrate. The single crystal used as a substrate is an oxide single crystal possessing a crystal structure of the K.sub.2 NiF.sub.4 type and having a composition of Sr.sub.1-X La.sub.1-Y Ga.sub.1-Z O.sub.4-W (wherein X, Y, Z, and W fall in the following respective ranges; -0.1<X<0.1, -0.1<Y<0.1, -0.1<Z<0.1, and -0.4<W<0.4).
    Type: Grant
    Filed: June 21, 1991
    Date of Patent: May 9, 1995
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventor: Kozo Nakamura
  • Patent number: 5409892
    Abstract: A method of manufacturing a superconductor by applying a floating zone method to a raw material sintered ingot. This method is adapted to obtain an elongated superconductor which can provide high critical current density. A floating zone is moved along the raw material sintered ingot with such speed difference that the speed in its forward end portion is higher than that in its rear end portion, thereby to obtain a superconductor having a smaller diameter. In order to attain a higher crystal orientation property, it is preferable to select the product of the diameter (D mm) of a superconductor provided with a crystal orientation property, which is produced after passage of the floating zone, and the speed (V mm/h) for moving the floating zone in a range of 0.5.ltoreq.DV.ltoreq.20 and to select pressure P of an atmosphere encircling the floating zone in a range of 0<P.ltoreq.3 [kgf/cm.sup.2 ] as well as to pass the floating zone along the raw material sintered ingot at least twice.
    Type: Grant
    Filed: October 21, 1993
    Date of Patent: April 25, 1995
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Kazuhiko Hayashi, Hisao Nonoyama, Misayuki Nagata
  • Patent number: 5407907
    Abstract: A method of pulling a crystal of a metal oxide is disclosed, in which the growth of the crystal is performed in a liquid phase having a composition which is different from the metal oxide and which contains components constituting the metal oxide. The liquid phase is in contact with a solid phase located at a position separated from the position at which the crystal of the metal oxide grows. The solid phase has a composition different from that of the metal oxide and supplies components constituting the metal oxide to the liquid phase.
    Type: Grant
    Filed: May 21, 1993
    Date of Patent: April 18, 1995
    Assignees: International Superconductivity Technology Center, Asahi Glass Co., Ltd., Ishikawajimaharima Jukogyo Kabushiki Kaisha, Sumitomo Metal Industries, Ltd., Kyushu Electric Power Co., Railway Technical Research Institute
    Inventors: Yasuji Yamada, Teruo Izumi, Kanshi Ohtsu, Yuichi Nakamura, Kengo Ishige, Yuh Shiohara, Minoru Tagami, Shoji Tanaka
  • 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: 5376622
    Abstract: A melting-and-solidification manufacturing method for manufacturing an ingot of a high critical temperature superconductive oxide belonging, in particular, to the YBaCuO, BiSrCaCuO, or TlBaCaCuO families, wherein:an ingot of oxide having the appropriate stoichiometery is used;the ingot is held horizontally by levitation on a film of gas inside a furnace;the ingot is melted;a vertical thermal gradient is established inside said furnace such that nucleation starts at the bottom portion of said ingot;while maintaining said thermal gradient, the overall temperature of the furnace is lowered at a rate of not more than 0.1.degree. C./hour down to the temperature which corresponds to complete ingot solidification; andfinally, conventional oxygenation treatment is applied to said ingot.
    Type: Grant
    Filed: March 31, 1993
    Date of Patent: December 27, 1994
    Assignee: Alcatel Alsthom Compagnie Generale d'Electricite
    Inventor: Christian Belouet
  • 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: 5369090
    Abstract: A process for producing Bi-based oxide superconductor single crystals by the floating zone method is disclosed, which comprises using a feed rod of an oxide comprising a formulation of metallic elements represented by the following general formula:Bi.sub.p Sr.sub.q Ca.sub.r Cu.sub.2 O.sub.ywherein2.00< p< 2.18, 1.87< q< 2.00, 0.9.ltoreq. r.ltoreq. 1.0,and y is a positive number, in a moving rate of said rod of from 0.1 to 0.35 mm per hour in the side where crystals are accumulated, in which preferably, in the initial stage of the formation of crystals, the diameters of the rod-like crystals to be accumulated are changed in the wavelike state, and more preferably, in the middle stage of the subsequent formation of crystals, the amount of change thereof is gradually decreased.
    Type: Grant
    Filed: April 15, 1993
    Date of Patent: November 29, 1994
    Assignee: International Superconductivity Technology Center
    Inventors: Kenshi Takamuku, Genda Gu, Naoki Koshizuka
  • Patent number: 5314871
    Abstract: According to the present invention, when a superconductive thin film is formed on a substrate of a single crystal, a compound having a composition of SrNdGaO.sub.4 and a K.sub.2 NiF.sub.4 type crystal structure is used as a material employable for the substrate. Alternatively, a single crystal composed of an oxide in which Ca, La and Cr are added to the foregoing compound is used as a material employable for the substrate. Then, a superconductive thin film composed of an oxide is formed on the substrate by employing an epitaxial growing method. Thus, the present invention makes it possible to provide a superconductive material having an excellent property of lattice alignment, a stable and high critical superconductivity temperature and a stable critical superconductivity electric current.
    Type: Grant
    Filed: May 21, 1993
    Date of Patent: May 24, 1994
    Assignee: Kabushiki Kaisha Komatsu Seisakusho
    Inventor: Kozo Nakamura
  • Patent number: 5312804
    Abstract: A method of fabricating a superconductive flexible conductor having a high critical temperature in which method a deposit of superconductive ceramic is applied to a metal tape of thickness lying in the range 0.1 mm to 1 mm, wherein:the deposit of thickness lying in the range 50 .mu.m to 300 .mu.m and of concentration by volume of not less than 70% runs through an infrared beam at a speed of not less than 5 cm per minute, the zone treated by the the beam having a width of less than 10 mm relative to the travel direction and a surface temperature of not less than 1200.degree. C., thereby imparting a surface superconductive layer to the deposit which is of concentration by volume close to 100%, which is textured in the travel direction, and which is of thickness lying in the range 10 .mu.m to 100 .mu.m; andannealing is then performed under oxygen.
    Type: Grant
    Filed: October 28, 1992
    Date of Patent: May 17, 1994
    Assignee: Alcatel Cable
    Inventors: Alain Petitbon, Roland Queriaud
  • Patent number: 5310706
    Abstract: A method for manufacturing a high Tc superconducting circuit elements is disclosed, which comprises the steps of preparing a single crystal conductive substrate of Sr.sub.2 RuO.sub.4 by a floating zone melting process; epitaxially growing on the (001)-surface of the Sr.sub.2 RuO.sub.4 substrate a high Tc copper oxide-based superconducting film with a thickness of 1 to 1000 nm; depositing metal pads onto said superconducting film to form electrical contacts; and applying a metal pad to the surface of the substrate to form an electrical contact.
    Type: Grant
    Filed: July 16, 1993
    Date of Patent: May 10, 1994
    Assignee: International Business Machines Corporation
    Inventors: Frank Litchenberg, Jochen Mannhart, Darrell Schlom