Process Of Making Or Treating High Tc (above 30 K) Superconducting Shaped Material, Article, Or Device Patents (Class 505/725)
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Patent number: 8630687Abstract: In one aspect, a method is disclosed of making a material, the method including synthesizing a composition Sr2RuO4-ySy where y is in the range of, e.g., 0.1-1.2. In some embodiments y is in the range of 0.1-0.6. In some such embodiments, the material may exhibit a strong diamagnetic signal, e.g. of up to 5% of absolute diamagnetism (?=?¼?) or more (e.g., at temperatures ranging from 4K-300K). In some embodiments, the material may exhibit high temperature superconductivity.Type: GrantFiled: September 28, 2012Date of Patent: January 14, 2014Assignee: AVD ConductionInventors: Armen Gulian, Vahan Nikoghosyan, Dennis Winegarner
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Patent number: 7964533Abstract: The invention relates to a method for producing a high temperature superconductor (HTSC) from a strip including an upper side precursor layer and which, for continuous sintering of the precursor layer within a furnace in the presence of a fed-in reaction gas, is drawn across a support. A furnace for performing the method is also described.Type: GrantFiled: February 15, 2008Date of Patent: June 21, 2011Assignee: Zenergy Power GmbHInventor: Michael Baecker
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Patent number: 7135438Abstract: A class of superconductive materials containing copper-oxygen bonding and with mixed cation-occupancy designed with a view to size and valence consideration yield useful values of critical temperature and other properties. Uses entail all applications which involves superconducting materials such as magnets and transmission lines which require continuous superconductivity paths as well as detectors (e.g., which may rely on tunneling).Type: GrantFiled: April 19, 1993Date of Patent: November 14, 2006Assignee: Lucent Technologies Inc.Inventors: Bertram Josef Batlogg, Robert Joseph Cava, Robert Bruce van Dover
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Patent number: 6982240Abstract: A superconducting device operable at temperatures in excess of 30° K. and a method for making the device are described. A representative device is an essentially coplanar SQUID device formed in a single layer of high Tc superconducting material, the SQUID device being operable at temperatures in excess of 60° K. High energy beams, for example ion beams, are used to convert selected portions of the high Tc superconductor to nonsuperconductive properties so that the material now has both superconductive regions and nonsuperconductive regions. In this manner a superconducting loop having superconducting weak links can be formed to comprise the SQUID device.Type: GrantFiled: May 9, 1991Date of Patent: January 3, 2006Assignee: International Business Machines CorporationInventors: Gregory John Clark, Richard Joseph Gambino, Roger Hilsen Koch, Robert Benjamin Laibowitz, Allan David Marwick, Corwin Paul Umbach
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Patent number: 6794337Abstract: The present invention relates to a superconducting colloid prepared by an exfoliating multi-layered superconductor, represented by the formula Bi2Sr2Cam−1CumO2m+4+&dgr; (wherein, m is 1, 2 or 3 and &dgr; is a positive number greater than 0 and less than 1) in which a mercuric halide-organic complex is intercalated, a process thereof, a superconducting thin layer prepared using the above superconducting colloid, and a process thereof.Type: GrantFiled: January 8, 2002Date of Patent: September 21, 2004Inventors: Jin Ho Choy, Soon Jae Kwon, Eui Soon Chang
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Patent number: 6740259Abstract: A method of manufacture of a ceramic material comprises the steps of preparing a melt of the ceramic materials, cooling the melt slowly through the freezing point of the material to initiate solidification, holding the melt at a temperature below the freezing point of the material whilst solidification progresses and characterised in that during solidification an ultrasonic field is applied to the melt. The melt composition may be selected to include an excess of one or more ceramic materials so as to produce a second phase dispersed in the solidified product during solidification. Also claimed is a ceramic material produced by the method described. The ceramic material may be a superconductor.Type: GrantFiled: November 8, 2001Date of Patent: May 25, 2004Assignee: Qinetiq LimitedInventors: Jonathan C Fitzmaurice, David R Moore
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Patent number: 6653259Abstract: A method of fabricating large bulk high temperature superconducting articles which comprises the steps of selecting predetermined sizes of crystalline superconducting materials and mixing these specific sizes of particles into a homogeneous mixture which is then poured into a die. The die is placed in a press and pressurized to predetermined pressure for a predetermined time and is heat treated in the furnace at predetermined temperatures for a predetermined time. The article is left in the furnace to soak at predetermined temperatures for a predetermined period of time and is oxygenated by an oxygen source during the soaking period.Type: GrantFiled: December 20, 2001Date of Patent: November 25, 2003Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space AdministrationInventors: Ronald J. Koczor, Robert A. Hiser
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Patent number: 5932524Abstract: A high Tc superconducting ceramic material is produced by a method in which a mixture of chemicals in suitable amounts is compacted into a desired form. The compacted mixture is then fired and, at the same time, an electric current is caused to pass through the compacted mixture in a predetermined direction. By virtue of the passage of the current through the material during firing, the orderliness of the molecular arrangement is enhanced and an elevated transition temperature Tc is obtained.Type: GrantFiled: September 27, 1990Date of Patent: August 3, 1999Assignee: Semiconductor Energy Laboratory Co., Ltd.Inventor: Shunpei Yamazaki
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Patent number: 5845395Abstract: A high-temperature superconductor (HTS) thin film device such as a patch antenna or a microstrip line is produced by using a substrate of a low-permittivity material such as polytetrafluoroethylene in which fine particles of glass fiber are dispersed. Initially a HTS film is deposited on a conventional MgO or SrTiO.sub.3 substrate by sputtering or laser ablation. The low-permittivity substrate is bonded to the HTS film on the oxide substrate with an adhesive, and then the oxide substrate is removed by grinding or abrasion. After that the HTS film on the low-permittivity substrate is patterned. Since the low-permittivity substrate is small in the degree of wavelength shortening, current density in the HTS film reduces and therefore power loss of the device decreases.Type: GrantFiled: September 11, 1996Date of Patent: December 8, 1998Assignee: NEC CorporationInventor: Kazuhiko Honjo
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Patent number: 5795849Abstract: A method for producing a superconductor assembly includes preparing a first bulk ceramic superconductor having a first essentially random pattern of superconductor domains of a copper-oxide ceramic superconductor and non-superconductor domains at a critical temperature, and preparing a second bulk ceramic superconductor having a second essentially random pattern of superconductor domains of a copper-oxide ceramic superconductor and non-superconductor domains at the critical temperature. The method further includes juxtaposing a first surface of the first bulk ceramic superconductor proximate with a first surface of the second bulk ceramic superconductor to form a superconductor assembly where superconductor domains of the first bulk ceramic superconductor and superconductor domains of the second bulk ceramic superconductor are only randomly aligned due to the different first essentially random pattern and second essentially random pattern.Type: GrantFiled: June 7, 1995Date of Patent: August 18, 1998Inventor: Paul L. Hickman
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Patent number: 5643856Abstract: 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: GrantFiled: March 31, 1995Date of Patent: July 1, 1997Assignee: Massachusetts Institute of TechnologyInventors: Gregory J. Yurek, John B. Vander Sande
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Patent number: 5591698Abstract: A melt textured growth process for bulk YBCO at temperatures below 950.degree. C. is provided so that the material (YBCO) can be combined with silver to produce bulk superconductors by providing a combination of precursors that provide melting at 950.degree. C. or lower temperatures. After melting of the thoroughly mixed precursors, the sample is cooled in a controlled temperature environment. The process makes it possible to use metallic silver or other normal metals such as gold, as components in the fabrication of long YBCO wires and cables while achieving a high critical current density.Type: GrantFiled: December 29, 1994Date of Patent: January 7, 1997Assignee: University of HawaiiInventors: Steven Y. Song, James R. Gaines
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Patent number: 5578551Abstract: The present invention is a controlled vapor/solid reaction process for the synthesis of samples of bulk compositions with a structure defined by the homologous series HgBa.sub.2 Ca.sub.n-1 Cu.sub.n O.sub.2n+2+.delta. [Hg-12(n-1)n] with n=2, 3, . . . with up to 75 to 90% Hg-1212 and 65 to 75% Hg-1223 by volume, which display sharp superconducting transitions up to 135 K.Type: GrantFiled: July 28, 1993Date of Patent: November 26, 1996Assignee: University of HoustonInventors: Ching-Wu Chu, Ruling Meng, Y. Q. Wang
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Patent number: 5578555Abstract: A method of monitoring the fabrication of a superconductive material having a high critical temperature is wherein:the starting material is a mixture of powders of precursors for said material having stoichiometric proportions appropriate for the desired superconductive phase;the said mixture is agglomerated to form a tubular or a cylindrical piece;the agglomerated piece is placed in a controlled-atmosphere oven for synthesizing said superconductive phase;the conductivity of said piece is measured continuously;the temperature at which conductivity begins to decrease is exceeded and then the temperature is returned to a value where conductivity begins to increase; andthe temperature of the oven is permanently adjusted so that said conductivity does not decrease.Type: GrantFiled: November 23, 1994Date of Patent: November 26, 1996Assignee: Alcatel Alsthom Compagnie Generale d'ElectriciteInventor: G erard Duperray
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Patent number: 5559084Abstract: Disclosed are a composition and a method of preparing a composition of the formula R.sub.2 Q.sub.4 Cu.sub.7 O.sub.x, wherein R is a rare-earth ion or a mixture of rare earth ions, and Q is Ba, or Ba combined with either Sr or Ca or both Sr and Ca. Such compositions have a unique crystalline structure and are superconducting oxides.Type: GrantFiled: May 28, 1991Date of Patent: September 24, 1996Assignee: Massachusetts Institute of TechnologyInventors: John B. Vandersande, Gregory J. Yurek, Toshihiro Kogure
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Patent number: 5547924Abstract: A superconductive ceramic composite material with high strength and capable of plastic deformation is prepared by mixing and sintering a superconductive powder represented by (RE.sub.x AE.sub.1-x).sub.1-y Cu.sub.y O.sub.z (RE represents Y or a rare-earth element having an atomic number of 57-71, or a combination of at least two of these elements, AE is at least one of alkaline earth elements Ca, Sr and Ba, x is 0.13-0.67, y is 0.25-0.67, and z is 1.08-1.17) and a metal powder M (M represents at least one of noble metals Rh, Pd, Ag, Ir, Pt and Au), in a defined ratio. The deformation (e.g., rolling) is followed by reheat-treatment (resintering). The powder mixture can be enclosed in a metallic capsule or made into a clad sheet by interposing the powder within two metallic sheets, and deformed (drawn or press formed into a desired shape) followed by sintering. The composite material may contain a superconductive network of such grains.Type: GrantFiled: September 21, 1995Date of Patent: August 20, 1996Assignee: Aisin Seiki Kabushiki KaishaInventors: Yoshitaka Ito, Masami Ishii, Takayuki Nishio, Uichiro Mizutani, Yuh Yamada, Fumihiko Ogasawara, Motohiro Suganuma
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Patent number: 5534490Abstract: Provided is an Hg-Ba-Ca-Cu-O oxide superconductor having a high superconductivity transition temperature Tc and a method which can prepare the same in excellent reproducibility. This oxide superconductor consists essentially of Hg, Ba, Ca, Cu and O, and is expressed in a chemical formula (Hg.sub.1-X Cu.sub.X)Ba.sub.2 Ca.sub.2 Cu.sub.3 O.sub.Y, wherein X=0.05 to 0.7 and Y=8 to 8.75. A method of preparing the oxide superconductor comprises a step of mixing raw materials of Hg, Ba, Ca and Cu with each other so that (Hg+Ba):Ca:Cu=b:1:C and Hg:Ba=(1-a):a, wherein 0.625.ltoreq.a.ltoreq.0.714, 1.ltoreq.b.ltoreq.3 and 1.667.ltoreq.c.ltoreq.3.444, in mole ratio, and compression-molding the mixture, and a step of heat treating a compact obtained by the compression molding. This oxide superconductor has a superconductivity transition temperature Tc of 134 K., which is the highest at present.Type: GrantFiled: June 23, 1994Date of Patent: July 9, 1996Assignees: Sumitomo Electric Industries, Ltd., Tohoku Electric Power Co., Inc., Matsushita Electric Industrial Co., Ltd., International Superconductivity Technology CenterInventors: Makoto Itoh, Ayako Yamamoto, Kazuyuki Isawa, Seiji Adachi, Hisao Yamauchi, Shoji Tanaka
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Patent number: 5525585Abstract: 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: GrantFiled: June 16, 1994Date of Patent: June 11, 1996Assignee: Korea Advanced Institute of Science and TechnologyInventors: Jeong-Hun Suh, Young A. Jee, Suk-Joong L. Kang, Duk Y. Yoon
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Patent number: 5492886Abstract: Novel superconducting materials in the form of compounds, structures or phases are formed by performing otherwise known syntheses in a highly oxidizing atmosphere rather than that created by molecular oxygen at atmospheric pressure or below. This leads to the successful synthesis of novel superconducting compounds which are thermodynamically stable at the conditions under which they are formed.Type: GrantFiled: April 15, 1994Date of Patent: February 20, 1996Assignee: Regents of the University of CaliforniaInventor: Donald E. Morris
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Patent number: 5459124Abstract: 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: GrantFiled: October 29, 1993Date of Patent: October 17, 1995Assignees: International Superconductivity Technology Center, Shinkoku Electric Power Co., Inc., Nippon Steel CorporationInventors: Terutsugu Oyama, Masato Murakami, Naoki Koshizuka, Shoji Tanaka
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Patent number: 5439880Abstract: 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: GrantFiled: May 3, 1993Date of Patent: August 8, 1995Assignee: Massachusetts Institute of TechnologyInventors: Gregory J. Yurek, John B. Vander Sande
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Patent number: 5430010Abstract: The present invention relates to a process for preparing an oxide superconductor having a high critical current density, a uniform structure and an excellent mechanical property and thermal stability, which comprises heating raw material powders of a REBaCuO system at 1050.degree. C. or higher, cooling the material for solidification, pulverizing and mixing the solidified material to homogeneously disperse the structure of the solidified material, molding the material, optionally mixed with silver oxide or silver, into a predetermined shape, and reheating the molding to 1050.degree. C. or higher to grow a superconducting phase.Type: GrantFiled: June 8, 1993Date of Patent: July 4, 1995Assignees: International Superconductivity Technology Center, Nippon Steel CorporationInventors: Masato Murakami, Terutsugu Oyama, Hiroyuki Fujimoto, Naoki Koshizuka, Yu Shiohara, Shoji Tanaka
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Patent number: 5430008Abstract: Superconducting materials and methods of forming superconducting materials are disclosed. Highly oxidized superconductors are heated at a relatively high temperature so as to release oxygen, which migrates out of the material, and form a non-superconducting phase which does not diffuse out of grains of the material. The material is then reoxidized at a lower temperature, leaving the non-superconducting inclusions inside a superconducting phase. The non-superconducting inclusions act as pinning centers in the superconductor, increasing the critical current thereof.Type: GrantFiled: October 28, 1991Date of Patent: July 4, 1995Assignee: The Regents of the University of CaliforniaInventor: Donald E. Morris
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Patent number: 5413980Abstract: Polycrystalline high-T.sub.c superconductors of the formula M.sub.m E.sub.e RO.sub.x, which contain grains which are crystallographically aligned to the greatest possible extent, where M is at least one trivalent element such as a lanthanide element, E is at least one divalent element such as an alkaline earth element and R is at least one transition metal such as Cu, and x denotes the proportion of oxygen, are obtained by substituting a part of the alkaline earth element by a foreign element, preferably an alkali-metal element, which is no longer present in the product after the reaction sintering and sintering except for contents in the ppm to parts per thousand range and brings about the orientation effect. This produces a material which contains a slight deficit of E and optionally M, has an unaltered critical temperature and is substantially more resistant to external agents than equivalent known materials. A post-treatment in a stream of air or oxygen is unnecessary.Type: GrantFiled: August 23, 1990Date of Patent: May 9, 1995Assignee: Hoechst AktiengesellschaftInventors: Joachim Maier, Albrecht Rabenau, deceased, Pandijan Murugaraj
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Patent number: 5411938Abstract: 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: GrantFiled: July 30, 1993Date of Patent: May 2, 1995Assignee: University of ChicagoInventors: Weite Wu, Cha Y. Chu, Kenneth C. Goretta, Jules L. Routbort
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Patent number: 5380702Abstract: A method for improving the phase purity of a multiphase ceramic high temperature superconductor by selective microwave heating of undesired phases in a multiphase material to cause a phase transformation of the undesired phase to the desired phase. The selective microwave heating may be employed during initial firing and sintering of the ceramic superconductor compound or as a subsequent annealing step. Plane polarized microwave energy may be employed to enhance the two dimensional anisotropy of the compound by similar selective heating.Type: GrantFiled: June 4, 1990Date of Patent: January 10, 1995Inventor: David L. Henty
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Patent number: 5380703Abstract: A superconductive fullerene and a process for making such superconductive fullerene are provided. The process involves contacting-a quantity of fullerene with the vapor of an interhalogen compound such as ICl. The halogen doped fullerenes exhibited a transition temperature above 60 K.Type: GrantFiled: January 25, 1993Date of Patent: January 10, 1995Assignee: The Research Foundation of State University of New York at BuffaloInventors: Yi-Han Kao, Liwei Song, Deborah D. L. Chung, Kevin T. Fredette
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Patent number: 5376622Abstract: 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: GrantFiled: March 31, 1993Date of Patent: December 27, 1994Assignee: Alcatel Alsthom Compagnie Generale d'ElectriciteInventor: Christian Belouet
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Patent number: 5371066Abstract: A precursor material is superoxidized to a superconducting oxide material in an atmosphere containing a reactive component that reacts with and removes hydroxide ion (OH.sup.-), replacing it with peroxide ion (O.sup.-). Preferred reactive components include H.sub.2 O.sub.2, N.sub.2 O, and I.sub.2. The reactive component reacts with and removes hydroxide ion from the precursor material, to reach a higher oxidation state in the superconducting oxide material than possible by oxidation in molecular oxygen. The use of such a reactive component permits both faster oxidation of the precursor material at conventional temperatures and the use of lower temperatures to achieve oxidation.Type: GrantFiled: June 5, 1992Date of Patent: December 6, 1994Assignee: Hughes Aircraft CompanyInventors: Ricardo C. Pastor, Antonio C. Pastor, deceased, Luisa E. Gorre, deceased, Keith C. Fuller
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Patent number: 5369087Abstract: 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: GrantFiled: July 11, 1991Date of Patent: November 29, 1994Assignee: Noranda Inc.Inventors: Philip R. Critchlow, Julian Cave
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Patent number: 5348936Abstract: Superconducting, metal-doped fullerenes are provided, along with processes for their preparation in relatively high stoichiometric purity. In one embodiment, the processes provide fullerenes of the formula M.sub.x C.sub.q, where M is a metal, x is greater than 0 but less than about 10, and q is at least 60. The processes comprise contacting C.sub.q with metal in an amount and under reaction conditions effective to produce a compound having the formula M.sub.y C.sub.q, and contacting said M.sub.y C.sub.q with a portion of C.sub.q in an amount and under reaction conditions effective to produce said M.sub.x C.sub.q, wherein y is greater than x.Type: GrantFiled: April 16, 1993Date of Patent: September 20, 1994Assignee: The Trustees of the University of PennsylvaniaInventors: John P. McCauley, Jr., Qing Zhu, Gavin Vaughan, Nicole Coustel
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Patent number: 5344816Abstract: High temperature superconducting oxide materials can be taken to a higher, but stable, state of oxidation by removing H-impurities, such as OH.sup.-, using I.sub.2 /O.sub.2 mixtures in a reactive atmosphere process. A higher T.sub.c and a narrower .DELTA.T-transition result.Type: GrantFiled: February 24, 1993Date of Patent: September 6, 1994Assignee: Hughes Aircraft CompanyInventors: Ricardo C. Pastor, Antonio C. Pastor, deceased, Luisa E. Gorre, deceased, Keith C. Fuller
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Patent number: 5338722Abstract: Superconducting oxide ceramics having a high density of superconducting current are formed without making use of very high temperatures higher than 1000.degree. C. Superconducting oxide material is placed in a crucible, melted and fired at a relatively low temperature. During the melting and firing step, the partial pressure of oxygen is reduced in order to lower the melting point of the ceramic. After the firing, the partial pressure of oxygen is increased.Type: GrantFiled: March 12, 1993Date of Patent: August 16, 1994Assignee: Semiconductor Energy Laboratory Co., Ltd.Inventor: Yasuhiko Takemura
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Patent number: 5334557Abstract: A method of preparing a powder of YBaCuO [phase 123] suitable for forming by drawing-lamination, which includes:preparing a powdered reactive mixture of precursors of purity greater than 99% and with a stoichiometry accurate to within less than 1%,binding this powdered reactive mixture to form intermediate pieces less than two millimeters in thickness which are placed in an oven so that their contact with a support is as small as possible,a heat treating the intermediate pieces,dry grinding the intermediate pieces to obtain grains of said powder with an average diameter of the order of a few .mu.m.Type: GrantFiled: March 3, 1993Date of Patent: August 2, 1994Assignee: Alcatel Alsthom Compagnie Generale d'ElectriciteInventors: Grard Duperray, Claudette Audry, Francoise Ducatel
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Patent number: 5334579Abstract: A process for producing a superconducting material comprising a compound oxide represented by the general formula:(Ba, Ca).sub.x (.alpha., Dy).sub.1-x Tl.sub.y Cu.sub.1-y O.sub.3-zwherein ".alpha." represents Y or La; the atomic ratio of Ca to Ba is between 1% and 90%; the atomic ratio of Dy to .alpha. is between 1% and 90%; x, y and z are within the ranges of 0.ltoreq.x.ltoreq.1, 0.ltoreq.y.ltoreq.1, and 0.ltoreq.z<1 respectively; and the expression of (Ba, Ca) and (.alpha., Dy) means that the respective elements occupy predetermined sites in a crystal in a predetermined proportion. The process comprises preparing a material powder, compacting the material powder and then subjecting the resulting compact to a final sintering operation and is characterized in that the material powder is(A) a powder mixture composed of powders selected from a group comprising (i) powders of elemental Ba, Cu, Ca, .alpha., Dy and Tl and (ii) powders of compounds each containing at least one of said elements Ba, Cu, Ca, .Type: GrantFiled: December 31, 1992Date of Patent: August 2, 1994Assignee: Sumitomo Electric Industries, Ltd.Inventors: Hideo Itozaki, Saburo Tanaka, Nobuhiko Fujita, Shuji Yazu, Tetsuji Jodai
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Patent number: 5332721Abstract: An improved technique for the fabrication of thallium-based superconducting oxides, and particularly Tl:Ba:Ca:Cu:O 2223 oxides, is described which allows production of very pure superconductors (>95% 2223 phase) having excellent structural characteristics. The method of the invention involves first forming a self-sustaining body of starting oxides and subjecting this body to a sintering technique wherein the temperature of the body is gradually raised to a maximum level of about 850.degree.-930.degree. C., followed by maintaining the body at this temperature for a period of about 48 hours. The body is then slowly cooled to avoid distortion and loss of superconducting character. Most preferably, the sintering is a two-stage operation, wherein the body is first heated a relatively low rate (e.g., 1.degree.-10.degree. C./min.) to a temperature of about 650.degree.-750.degree. C., followed by faster heating at a higher rate to achieve the maximum sintering temperature.Type: GrantFiled: October 21, 1992Date of Patent: July 26, 1994Assignees: Midwest Superconductivity, Inc., The University of ArkansasInventors: Ying Xin, Zhengzhi Sheng, Yufang Li
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Patent number: 5326747Abstract: A process for patterning layered thin films comprising a bottom oxide superconductor (1) layer deposited on a substrate (3) and another thin film (2) deposited on the bottom superconductor layer and consisting of insulator, ordinary conductor or oxide superconductor having a different crystal orientation from the bottom superconductor layer. The bottom superconductor layer (1) is subjecting to heat-treatment before another thin film (2) is deposited thereon. The heat-treatment can be carried out under a first condition in ultra high-vacuum at a temperature which is lower than the oxygen-trap temperature (T.sub.trap) at which oxygen can enter into the oxide superconductor but is higher than a temperature which is lower by 100.degree. C. than the oxygen-trap temperature (T.sub.trap -100.degree. C.) or under a second condition in an atmosphere containing oxygen of high purity at a temperature which is higher than the oxygen-trap temperature (T.sub.Type: GrantFiled: April 9, 1992Date of Patent: July 5, 1994Assignee: Sumitomo Electric Industries, Ltd.Inventors: Hiroshi Inada, Michitomo Iiyama
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Patent number: 5324495Abstract: The present invention relates to a new process for making metal fulleride compositions having the formula A.sub.n (C.sub.x).sub.m, wherein A is a metal cation and C.sub.x is a fullerene anion, preferably C.sub.x is C.sub.60 or C.sub.70, wherein n is a number equal to the absolute value of the valence of the fullerene anion, wherein m is equal to the absolute value of the valence of A, wherein the values of n and m are divided by their greatest common factor, if any, and wherein the metal fulleride composition is neutral in charge. This process comprises reacting a metal with a fullerene in a solvent or mixture of solvents in which the fullerene is at least partly soluble at a temperature from greater than the freezing point to equal to or less than the boiling point of the solvent, for a time sufficient to form the metal fulleride composition.Type: GrantFiled: October 8, 1993Date of Patent: June 28, 1994Assignee: Exxon Research and Engineering CompanyInventor: Sergiu M. Gorun
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Patent number: 5318745Abstract: A method of manufacturing an oxide superconductor having a composition expressed by formula La.sub.2-X Sr.sub.X CaCu.sub.2 O.sub.6 (0<X.ltoreq.0.6), comprising the steps of: preliminarily burning a raw powder having a predetermined composition, and sintering the powder to obtain a sintered body; and subjecting the sintered body to hot isostatic pressing at a temperature falling within a range of from 940.degree.-1600.degree. C. under total pressure of 10 MPa or more and oxygen partial pressure of 2 MPa or more. By virtue of the step of subjecting the sintered body to hot isostatic pressing, a superconductor can be manufactured at a temperature and under a pressure within respective wide ranges. Further, the composition of the superconductor can be selected within a wide range of 0<X.ltoreq.0.6. Moreover, the superconductor can be manufactured by performing quenching after the hot isostatic pressing.Type: GrantFiled: July 8, 1992Date of Patent: June 7, 1994Assignees: International Superconductivity Technology Center, Mitsubishi Materials Corporation, Hitachi, Ltd.Inventors: Takeshi Sakurai, Toru Yamashita, Hisao Yamauchi, Shoji Tanaka
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Patent number: 5314867Abstract: 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: GrantFiled: July 25, 1991Date of Patent: May 24, 1994Assignee: University of ArkansasInventors: Allen M. Hermann, Zhengzhi Sheng
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Patent number: 5306700Abstract: A method is disclosed for fabricating bulk superconducting materials into shaped articles, including ones of relatively large sizes and complex shapes, which have high densities, high integrity, high magnetization and critical current densities. A mixture of superconducting material is completely or substantially melted and the molten material is then cooled to room temperature and ground to a powder. The ground powder is next mixed with a second phase made up of either precursor superconducting powder or a mixture of metallic silver and copper. The resulting mixture is then shaped into an article by conventional ceramic article forming techniques: pressing, extruding, molding or the like. The resulting shaped article is heated to a temperature at which a substantial amount of its content of second phase material is melted, thus facilitating densification of the entire shaped article. The resulting dense specimen is annealed in an appropriate environment while it is being cooled to room temperature.Type: GrantFiled: September 1, 1992Date of Patent: April 26, 1994Assignee: The Catholic University of AmericaInventor: Hamid Hojaji
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Patent number: 5300486Abstract: A process and a precursor composition for preparing a lead-doped bismuth-strontium-calcium-copper oxide superconductor of the formula Bi.sub.a Pb.sub.b Sr.sub.c Ca.sub.d Cu.sub.e O.sub.f wherein a is from about 1.7 to about 1.9, b is from about 0.3 to about 0.45, c is from about 1.6 to about 2.2, d is from about 1.6 to about 2.2, e is from about 2.97 to about 3.2 and f is 10.+-.z by reacting a mixture of Bi.sub.4 Sr.sub.3 Ca.sub.3 Cu.sub.4 O.sub.16.+-.z, an alkaline earth metal cuprate, e.g., Sr.sub.9 Ca.sub.5 Cu.sub.24 O.sub.41, and an alkaline earth metal plumbate, e.g., Ca.sub.2-x Sr.sub.x PbO.sub.4 wherein x is about 0.5, is disclosed.Type: GrantFiled: May 27, 1993Date of Patent: April 5, 1994Assignee: The United States of America as represented by the United States Department of EnergyInventors: William L. Hults, Kimberly A. Kubat-Martin, Kenneth V. Salazar, David S. Phillips, Dean E. Peterson
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Patent number: 5300483Abstract: A method is provided for preparing a precursor of a superconductor containing atoms of oxygen, atoms of copper and atoms of at least two other metals and sufficient atoms of oxygen so that up to, but no more than, one atom of copper is in the trivalent state, in which method there are blended together, in finely divided particulate state, components containing atoms of the metals in the desired proportion with at least one of the components containing oxygen in an amount above that which would put more than one atom of copper into the trivalent state and thereafter milling the components together in a high energy system to a maximum particle size of about 5 microns for at least 99 weight percent of the blend.Type: GrantFiled: January 16, 1992Date of Patent: April 5, 1994Inventor: Shome N. Sinha
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Patent number: 5270293Abstract: A process for preparing a superconducting, ceramic material with an increased critical current is described. In this process, the materials used to form the superconducting material are mixed with at least one inorganic salt, and the mixture containing the salt is then heat treated. The salt is then leached from the heat-treated mixture.Type: GrantFiled: April 12, 1991Date of Patent: December 14, 1993Assignee: Alfred UniversityInventors: Walter A. Schulze, Sudhakar Gopalakrishnan
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Patent number: 5270295Abstract: A process for preparing a composition having the general formula REBa.sub.2 Cu.sub.4 O.sub.y where RE is a rare earth element such as dysprosium and including yttrium and the subscript "y" is about 8.0. The process utilizes nitric acid among the starting components to provide control over stoichiometry and minimize contamination. The present invention is also directed to a process of preparing a high purity superconductor utilizing the composition thus prepared. This process permits the superconductor to be prepared in a short time and at low sintering temperatures.Type: GrantFiled: April 20, 1992Date of Patent: December 14, 1993Assignee: Industrial Technology Research InstituteInventors: Weir M. Hurng, Sheng F. Wu, Cheng Y. Shei, Yao T. Huang
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Patent number: 5262398Abstract: A ceramic oxide superconductive composite material comprising a ceramic oxide superconductor and a non-superconductive material comprising at least one element which does not react with any of the elements of the ceramic oxide superconductor has improved superconductive properties such as a higher critical temperature and a larger critical current density.Type: GrantFiled: December 16, 1992Date of Patent: November 16, 1993Assignee: Sumitomo Electric Industries, Ltd.Inventors: Masayuki Nagata, Minoru Yokota, Ken-ichi Sato
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Patent number: 5262391Abstract: 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: GrantFiled: January 2, 1991Date of Patent: November 16, 1993Assignee: Nippon Steel CorporationInventors: Mitsuru Morita, Katsuyoshi Miyamoto, Kiyoshi Sawano, Shouichi Matsuda
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Patent number: 5260263Abstract: A superconductive ceramic wire material composed of rare earth elements, alkali earth metals, copper, and oxygen, which is obtained by mixing a powder containing oxides of the component elements of the superconductive ceramic with a solution containing organic compounds of the component elements, forming the mixture into a wire, and firing the wire in a temperature range from 850.degree. to 949.degree. C. in an oxygen-containing atmosphere.Type: GrantFiled: June 8, 1989Date of Patent: November 9, 1993Assignee: Ibiden Co., Ltd.Inventors: Ryo Enomoto, Yoshimi Matsuno, Masanori Tamaki
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Patent number: H1605Abstract: A closed flexible superconductive ribbon, is made to confine magnetic flux nd which is thereafter elongated and selectively twisted to form a desired type of magnetic field. The shape of the twist is varied for the particular application. A helical field source for twister type geometries, for example, can be implemented by winding the stretched superconducting loop around a cylindrical tube. In another embodiment, the superconductive ribbon is twisted into two halves, one of which is rotated 180.degree. with respect to the other. In such a configuration, two fields exist which are mutually opposite to each other.Type: GrantFiled: January 27, 1992Date of Patent: November 5, 1996Assignee: The United States of America as represented by the Secretary of the ArmyInventor: Herbert A. Leupold
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Patent number: RE35376Abstract: The present invention comprises novel oxide materials exhibiting bulk superconductivity up to and exceeding 85K and processes for their synthesis. The oxides are within the formula R.sub.a Ba.sub.b Cu.sub.c O.sub.d wherein 1.9<a<2.1, 3.9<b<4.1, 6.8<c<7.2, 14.4<d<15.2 and wherein R is Y or any of the lanthanide rare earth elements. Certain substitutions such as Ca and La on the R and Ba sites are included.Type: GrantFiled: December 28, 1994Date of Patent: November 5, 1996Assignee: Industrial Research LimitedInventors: Jeffrey L. Tallon, Robert G. Buckley, Donald M. Pooke