Other Rare Earth (i.e., Sc,y,ce,pr,nd,pm,sm,eu,gd,tb,dy,ho,er,tm,yb,lu) And Alkaline Earth (i.e., Ca,sr,ba,ra) Patents (Class 505/779)
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Patent number: 5356868Abstract: A single phase superconducting oxide ceramic material in the form of highly oriented platelets, and a process for the production thereof. The process involves calcining in a non-reducing atmosphere a homogeneous mixture of stoichiometric proportions of suitable precursor materials. The calcination temperature is below the peritectic melt temperature of the superconducting material, and is at or above a temperature and for a time sufficient to effect partial melting of at least one of the precursor materials to a degree sufficient to effect diffusion of at least one of the precursor materials throughout the mixture. The calcination vessel is not wetted by melts of the precursor materials at the calcination temperature. The calcined material is then annealed in a non-reducing atmosphere. A typical material produced by the process is YBa.sub.2 Cu.sub.3 O.sub.x superconducting material, at a calcination temperature of about 976.degree.-982.degree. C.Type: GrantFiled: July 3, 1989Date of Patent: October 18, 1994Assignee: GTE Laboratories IncorporatedInventors: Naomi Naito, Lorraine A. Jachim
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Patent number: 5328892Abstract: An oxide superconducting material having a composition represented by a formulaTlSr.sub.2 (Sr.sub.n-x Y.sub.x)Cu.sub.n+1 O.sub.5+2nwherein n=1 or 2 and 0.1.ltoreq.x.ltoreq.n is provided. This material has a high critical current density Jc even by sintering at a relatively low temperature of 850.degree.-880.degree. C.Type: GrantFiled: September 27, 1989Date of Patent: July 12, 1994Assignee: NEC CorporationInventors: Takashi Manako, Yuichi Shimakawa, Yoshimi Kubo
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Patent number: 5318949Abstract: A superconducting ceramic composition which is free of thallium, the composition having a unit cell containing two perovskite structure copper-oxygen planes and a rocksalt structure layer having a single plane containing cadmium.Type: GrantFiled: October 20, 1992Date of Patent: June 7, 1994Assignees: GEC-Marconi Limited, BICC Public Limited CompanyInventors: Martin R. Harrison, Simon R. Hall, Timothy P. Beales
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Patent number: 5308799Abstract: The present invention relates to an oxide superconductor comprising a composite oxide of RE , Ba and Cu, wherein the superconductor comprises a micro structure comprised of a monocrystalline REBa.sub.2 Cu.sub.3 O.sub.7-x phase (123 phase) and a RE.sub.2 BaCuO.sub.5 phase (211 phase) finely dispersed therein, the 123 phase being formed in a plurality of domains respectively for individual RE compositions and in the order of the 123 phase forming temperatures in respective layers.Type: GrantFiled: February 6, 1992Date of Patent: May 3, 1994Assignee: Nippon Steel CorporationInventors: Mitsuru Morita, Keiichi Kimura, Katsuyoshi Miyamoto, Kiyoshi Sawano, Seiki Takebayashi, Masamoto Tanaka
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Patent number: 5306697Abstract: A superconductor material having a current density, J, of from about 30,000 to about 85,000 amps/cm.sup.2 at zero magnetic field and 77.degree. K. is disclosed. The 123 superconductor, of the formula L.sub.1 Ba.sub.2 Cu.sub.3 O.sub.6 +.delta. wherein L is preferably yttrium, is capable of entrapping sufficiently high magnetic fields and exhibits a low microwave surface resistance. The process of preparing the superconductor comprises compacting the bulk product, L.sub.1 Ba.sub.2 Cu.sub.3 O, and then sintering the reaction product at a temperature between about 40.degree. C. to about 90.degree. C. below its melting point, i.e., for Y.sub.1 Ba.sub.2 Cu.sub.3 O.sub.6 +.delta. at a temperature of approximately 940.degree. C. The composition is then heated in a preheated chamber maintained at approximately 1090.degree. C. to about 1,200.degree. C. (approximately 1,100.degree. C. for Y.sub.1 Ba.sub.2 Cu.sub.3 O.sub.6 +.delta.Type: GrantFiled: August 23, 1991Date of Patent: April 26, 1994Assignee: University of Houston - University ParkInventors: Kamel Salama, Venkatakrishnan Selvamanickam
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Patent number: 5252544Abstract: An oxide superconductor which has a composition expressed by the following general formula and whose crystal structure is 1222-phase structure.Pb.sub.a (M.sub.1-x-y Ce.sub.x Sr.sub.y).sub.4 Cu.sub.3-a O.sub.z (I)(where M represents at least one element selected from the group consisting of Y, La, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, and Lu, and a, x, y, and z denote the numbers which satisfy 0.3.ltoreq.a.ltoreq.0.7, 0<x.ltoreq.0.25, 0.3.ltoreq.y<0.5, 8.5.ltoreq.z.ltoreq.9.5, respectively). A Pb-based Cu oxide superconductor manufacturing method comprising the steps of mixing powders of raw materials containing at least Pb, Sr, Ce, M (where M represents at least one element selected from the group consisting of Y, La, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, and Lu groups) and Cu in the proportion to have the composition shown in the general formula (I) above, optionally forming the mixed powder into a shape body, and firing the obtained powder mixture or the shape body in the temperature range of 900.degree.Type: GrantFiled: June 7, 1991Date of Patent: October 12, 1993Assignees: International Superconductivity Technology Center, Tohoku Electric Power Company, Incorporated, Kyocera Corporation, Central Research Institute of Electric Power Industry, The Furukawa Electric Co., Ltd.Inventors: Toshihiko Maeda, Kazuhiro Sakuyama, Shin-ichi Koriyama, Ataru Ichinose, Hisao Yamauchi, Shoji Tanaka
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Patent number: 5244871Abstract: An oxide superconductor comprises a composition represented by the composition formula: (Nd.sub.x --Ce.sub.y --L.sub.z).sub.2 CuO.sub.4-d (wherein L is an element selected from Ca and Mg, and x+y+z=1). The compositions of Nd, Ce and L of the oxide superconductor corresponds to a point falling inside an area of Nd--Ce--L ternary diagram surrounded by straight lines (A-B), (B-C), (C-D) and (D-A) connecting point (A) with point (B), point (B) with point (C), point (C) with point (D) and point (D) with point (A), respectively, the points (A), (B), (C) and (D) being points (x=1, y=0, z=0), (x=0.4, y=0.6, z=0), (x=0.4, y=0.3, z=0.3) and (x=0.1, y=0, z=0.9), respectively, in the Nd--Ce--L ternary diagram. Above-described Nd--Ce--L--Cu--O oxides can exhibit superconductivity within a wide range of composition when heat-treated in an atmosphere of nitrogen.Type: GrantFiled: October 9, 1991Date of Patent: September 14, 1993Assignees: Mitsubishi Metal Corporation, Hitachi, Ltd., International Superconductivity Technology CenterInventors: Takeshi Sakurai, Toru Yamashita, Hisao Yamauchi, Shoji Tanaka
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Patent number: 5242897Abstract: Complex superconducting oxides are fabricated through appropriate selection and use of fundamental superconducting "building blocks." In this fashion, the invention provides a rationalized method of fabricating complex oxides having desirably high T.sub.c values. In another aspect of the invention, novel, 112 and 12 superconducting oxides are described.Type: GrantFiled: October 28, 1991Date of Patent: September 7, 1993Assignee: The University of KansasInventors: Kai W. Wong, Xin Fei
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Patent number: 5241191Abstract: A cubic perovskite crystal structure is disclosed satisfying the unit cell formula:R.sub.0.33+z A.sub.0.67 C.sub.1-y O.sub.3-xwhereR, A and C represent rare earth, alkaline earth and copper atoms, respectively, capable of forming a superconductive R.sub.1 A.sub.2 C.sub.3 orthorhombic perovskite crystal structure;x is 0.67 to 1.0;y is up to 0.2; andz is up to 0.1.The crystal structure can be used to form superconductive superlattices and weak links for Josephson junction devices. The crystal structure can be produced by laser ablation deposition at a temperature below that required for the formation of a superconductive R.sub.1 A.sub.2 C.sub.3 orthorhombic perovskite crystal structure. The crystal structure can be used as a substrate for the subsequent deposition of an R.sub.1 A.sub.2 C.sub.3 orthorhombic perovskite crystal structure.Type: GrantFiled: December 31, 1991Date of Patent: August 31, 1993Assignee: Eastman Kodak CompanyInventors: John A. Agostinelli, Samuel Chen
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Patent number: 5217945Abstract: The present invention provides an oxide superconductor which has a relatively high transition temperature T.sub.c. This superconductor has the chemical formula (R.sub.1-x Ca.sub.x)(Ba.sub.1-y Sr.sub.y).sub.2 Cu.sub.3 O.sub.7-z wherein R is at least one rare earth element selected from the group consisting of Tm, Yb and Lu, x is with in the range of 0.1.ltoreq..times.0.5, y is within the range of 0.1.ltoreq. y .ltoreq.0.4 and z is within the range of 0.05 .ltoreq. z .ltoreq.(x/2+0.5). The invention further provides a method for producing the oxide superconductor which comprises firing a composition of the formula (R.sub.1-x Ca.sub.x)(Ba.sub.1-y Sr.sub.y).sub.2 Cu.sub.3 O.sub.7-z wherein R is at least one rare earth element selected from the group consisting of Tm, Yb and Lu, x is within the range of 0.1 .ltoreq..times..ltoreq.0.5 and y is within the range of 0.1 .ltoreq.y .ltoreq.0.4 at a temperature of from 750.degree. C. to the melting temperature of the composition under an oxygen partial pressure P(O.sub.Type: GrantFiled: September 5, 1991Date of Patent: June 8, 1993Assignees: Matsushita Electric Industrial Co., Ltd., Tohoku Electric Power Co., Inc., Central Research Institute of Electric Power Industry, The Tokyo Electric Power Co., Inc., International Superconductivity Technology CenterInventors: Takahiro Wada, Yuji Yaegashi, Ataru Ichinose, Nobuo Suzuki, Hisao Yamauchi, Shoji Tanaka
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Patent number: 5217949Abstract: Superconducting materials of the (T1,In)-Sr-Ca-Cu-O system-type are modified to raise their critical tempertures by substituting an element M for part of the Tl/In and optionally substituting Y or a rare earth element for some of the Ca.M is a transition metal with valency electrons in d orbitals in its normal state and having accessible tri-and/or tetra-valent states, that is V, Ti, Cr, Zr, Nb, Hf or Ta (which are preferred) Mn, Fe, Co, Ni, Mo, Rh, W, Os, Ir, Re or Ru.Type: GrantFiled: April 16, 1991Date of Patent: June 8, 1993Assignee: Lynxvale LimitedInventors: Ru-Shi Liu, Robert Janes, Wuzong Zhou, Peter P. Edwards
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Patent number: 5217947Abstract: Novel superconducting oxide compositions of the formulas (YBa.sub.2 Cu.sub.3.25).sub.a O.sub.z and Y.sub.2 Ba.sub.4 Cu.sub.8 O.sub.20-x (248) are provided which can have an ordered defect structure stacked on one axis. MiThis invention was made with Government support under contracts DMR-8616055 awarded by the National Science Foundation and F49620-88C-0004 awarded by the United States Air Force. The Government has certain rights in this invention.Type: GrantFiled: July 10, 1991Date of Patent: June 8, 1993Assignee: The Board of Trustees of the Leland Stanford Junior UniversityInventors: Roger W. Barton, Ann F. Marshall, Kookrin Char, Aharon Kapitulnik, Stephen S. Laderman, Mark Lee, Robert Hammond
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Patent number: 5200387Abstract: A compact superconductor of the empirical composition YBa.sub.2 Cu.sub.3 O.sub.7-x .times.zCuO, in which z is a number from 0.08 to 0.84, consists of elongated crystals grown together irregularly. It has a density of at least 5.9 g/cm.sup.3, in particular at least 6.02 g/cm.sup.3. It is prepared by mixing a fine-grained superconductor powder of the composition YBa.sub.2 Cu.sub.3 O.sub.7-x with 1 to 10% by weight of CuO, compressing the mixture under a pressure of at least 1 MPa to give a compact, and heating this compact at 940.degree.-985.degree. C. for at least 5 hours.Type: GrantFiled: July 17, 1990Date of Patent: April 6, 1993Assignee: Hoechst AktiengesellschaftInventors: Martin Schwarz, Iris Kullmer
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Patent number: 5190914Abstract: A superconducting material is disclosed which includes oxides of metals having the following composition:(Pb.sub.1-z Cu.sub.z) ((Sr.sub.1-y Ba.sub.y).sub.1-v Ca.sub.v).sub.2 (A.sub.1-x Ca.sub.x)Cu.sub.2wherein A is at least one element selected from the group consisting of Y, La, Nd, Sm, Eu, Gd, Ho, Er, Yb and mixtures of at least one of Y, La, Nd, Sm, Eu, Gd, Ho, Er and Yb with at least one of Tb, Tm and Lu, x, y, v and z are numbers satisfying the following conditions:0.ltoreq.x.ltoreq.0.4,0.1.ltoreq.y<0.7,0.ltoreq.v.ltoreq.0.2x, and2y-0.4.ltoreq.z.ltoreq.2y+0.2with the proviso that 0.6-x.ltoreq.z<1.0 when 0.ltoreq.x.ltoreq.0.2 and that 0.4.ltoreq.z<1.0 when 0.2.ltoreq.x.ltoreq.0.4. The superconducting material is produced by providing a blend of compounds of the metals in the metal oxides, and heating the blend at an oxygen partial pressure P of at least 0.001 atm and temperature of (860+40logP) .degree.C. to (1060+40logP) .degree.C.Type: GrantFiled: February 28, 1991Date of Patent: March 2, 1993Assignees: International Superconductivity Technology Center, Kyocera Corporation, Tohoku Electric Power Company, Inc., Furukawa Electric Co., Ltd.Inventors: Shin-ichi Koriyama, Kazuhiro Sakuyama, Toshihiko Maeda, Hisao Yamauchi, Shoji Tanaka
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Patent number: 5183799Abstract: Oxide materials of (L.sub.x A.sub.1-x).sub.i MO.sub.y, (L.sub.x A.sub.1-x).sub.i M.sub.1-z Cu.sub.z O.sub.y and (L.sub.x A.sub.1-x).sub.i MO.sub.j-.delta. G.sub.k, wherein L is Sc, Y, lanthanides, etc.; A is Ba, Sr. Ca, etc.; M is V, Nb, Ta, T, Zr or Hf; 0<x<1; 0<z<1; i=1, 3/2 or 2; 0<y.ltoreq.4; Gis F, Cl or N; .delta. is oxygen defect, and having a perovskite-like crystal structure, show superconductivity at a temperature higher than the liquid nitrogen temperature.Type: GrantFiled: July 10, 1991Date of Patent: February 2, 1993Assignee: Hitachi, Ltd.Inventors: Tetsuya Ogushi, Yoshinori Hakuraku, Hisanao Ogata
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Patent number: 5175140Abstract: A new high Tc superconducting compound oxide material represented by the general formula:AuBvCwCuxOyin which"A" is selected from the group consisting of magnesium(Mg), calcium(Ca), strontium(Sr) and barium(Ba);"B" is selected from the group consisting of yttrium(Y), lanthanum(La), and lanthanide elements;"C" is selected from the group consisting of vanadium (V), tantalum(Ta), indium(In), and thallium(Tl), and ##EQU1##Type: GrantFiled: August 3, 1990Date of Patent: December 29, 1992Assignee: Sumitomo Electric Industries, Ltd.Inventors: Nobuhiko Fujita, Tadakazu Kobayashi, Hideo Itozaki, Saburo Tanaka, Shuji Yazu, Tetsuji Jodai
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Patent number: 5151409Abstract: A superconducting oxide composition comprising Ln-Th-Cu-O wherein Ln indicates at least one element selected from a group consisting of Pr, Nd, Pm, Sm, Eu, Gd and Er. A superconducting structure is formed in such a manner that at least an insulating layer is sandwiched between two superconductor layers but the superconductor layers are electrically coupled with each other, and a superconducting device including the superconducting structure is constructed so as to perform a switching operation for an electric signal, to detect a light signal, and to detect the intensity of a magnetic field. Another superconducting device is formed so that two superconductor layers are put in direct contact with each other, and a tunnel current between the superconductor layers can be controlled.Type: GrantFiled: January 24, 1990Date of Patent: September 29, 1992Assignee: Hitachi, Ltd.Inventors: Masahiko Hiratani, Shin'ichiro Saitoh, Katsuki Miyauchi, Tsuyoshi Seko
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Patent number: 5149683Abstract: A method for producing an oxide superconductor formed according to a chemical composition formula (R.sub.1-x Ca.sub.x)(Ba.sub.1-y Sr.sub.y).sub.2 Cu.sub.4 O.sub.8 and having a transition temperature of 77K or above, comprising the step of causing a reaction between (R.sub.1-x Ca.sub.x)(Ba.sub.1-y Sr.sub.y).sub.2 Cu.sub.3 O.sub.7-z and a Cu material such as CuO, wherein R stands for one or more rare earth elements selected from the group consisting of Y, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm and Yb, and wherein 0.01.ltoreq.x.ltoreq.0.25, 0.ltoreq.y.ltoreq.0.5, and 0.ltoreq.z.ltoreq.1. The advantage of this production method is that this production method does not require a hot static pressing process which takes a long time.Type: GrantFiled: February 11, 1991Date of Patent: September 22, 1992Assignees: Matsushita Electric Industrial Co., Ltd., The Tokyo Electric Power Co., Inc., Central Research Institute of Electric Power Industry, Tohoku Electric Power Co., Inc., International Superconductivity Technology CenterInventors: Takahiro Wada, Nobuo Suzuki, Ataru Ichinose, Yuji Yaegashi, Hisao Yamauchi, Shoji Tanaka
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Patent number: 5149684Abstract: A process for preparing a superconductor-coated substrate including calcining a mixture of powdered yttrium or rare earth oxide (R), barium carbonate and copper oxide in a controlled atmosphere and in accordance with a predetermined temperature profile to form a superconductor powder having a stoichiometric ratio of R-Ba-Cu of approximately 1-2-3. The melting transition width of the resulting powder is relatively narrow, such that the melting onset temperature is above the high temperatures advantageously used to sinter the powder on the substrate.Type: GrantFiled: April 9, 1991Date of Patent: September 22, 1992Assignee: General AtomicsInventors: Lawrence D. Woolf, Frederick H. Elsner, Clyde H. Shearer
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Patent number: 5143895Abstract: The disclosed superconducting oxide material has a crystal structure of either Nd.sub.2 CuO.sub.4 type or oxygen-deficient perovskite type and mainly consists of a composition having a general chemical formula of (R.sub.1-x A.sub.x).sub.m+1 Cu.sub.m O.sub.3m+1-y, R being at least one rare earth element selected from the group consisting of Pr, Nd, Sm, Eu, Gd, Dy, Tb, Ho, Er, Tm, Yb, and Lu, A being Ce or Th, m being an integer of 1, 2, 3, . . . .infin. (m=.infin. standing for (R.sub.1-x A.sub.x)CuO.sub.3-y), 0.ltoreq.x.ltoreq.1, 0.ltoreq.y.ltoreq.m, Cu in the material having an average valence of not larger than +2 for all R, A, m, x, and y.The disclosed superconducting oxide material may have a general chemical formula of Nd.sub.2-x-z Ce.sub.x Sr.sub.z CuO.sub.4-y, 0.ltoreq.x.ltoreq.1, 0.ltoreq.y.ltoreq.1, and 0.ltoreq.z.ltoreq.1.The above superconducting oxide material can be made by mixing powdery starting materials for the composition, sintering the mixture at 1,000.degree. to 1,100.degree. C.Type: GrantFiled: January 25, 1990Date of Patent: September 1, 1992Assignee: The University of TokyoInventors: Shinichi Uchida, Yoshinori Tokura, Hidenori Takagi
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Patent number: 5140000Abstract: 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: July 31, 1990Date of Patent: August 18, 1992Assignee: Her Majesty The Queen in right of New ZealandInventors: Jeffrey L. Tallon, Robert G. Buckley, Donald M. Pooke
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Patent number: 5140005Abstract: A superconductive oxide powder is produced by a method comprising spray drying a slip to form agglomerates, feeding the agglomerates sequentially through a first and a second oxygen supported combustion flame for fusing the fine particles in the agglomerates to form an intermediate powder, annealing the intermediate powder in an oxygen-containing environment such as to produce a friable mass, and crushing the mass to form the superconductive oxide powder. For example, a precursor compound in the slip is barrium carbonate, the other precursor constituents are yttrium oxide and copper oxide, and the yttrium, barium and copper in atomic proportions in the precursor constituents are 1:2:3+Y where Y denotes a copper surplus having a value of up to about 1.5. In the final powder the proportions are 1:2:3+Z where Z is between about 0.2 and 1.0.Type: GrantFiled: February 4, 1988Date of Patent: August 18, 1992Assignee: The Perkin-Elmer CorporationInventors: Subramaniam Rangaswamy, Burton A. Kushner, Anthony J. Rotolico
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Patent number: 5126316Abstract: Compositions having the nominal formula Bi.sub.2 Sr.sub.3-x Y.sub.x Cu.sub.2 O.sub.8+y wherein x is from about 0.05 to about 0.45 and y is from about 0 to about 1 are superconducting.Type: GrantFiled: August 24, 1988Date of Patent: June 30, 1992Assignee: E. I. Du Pont de Nemours and CompanyInventors: Arthur W. Sleight, Munirpallam A. Subramanian
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Patent number: 5106829Abstract: A substantially single phase superconducting composition is formed from a of 1:2:3 molar ratio of fine powders of a superconducting rare earth oxide, CuO, and BaCo.sub.3. The mixed powders and shaped articles formed from the mixed powders are calcined, sintered, and cooled in an oxygen containing atmosphere. The cooling step is done slowly to convert the sample to the orthorhombic structure and to improve the superconducting properties. The article formed is a substantially single phase superconducting composition.Type: GrantFiled: September 19, 1990Date of Patent: April 21, 1992Assignee: The United States of America as represented by the Secretary of the NavyInventors: Syed B. Quadri, Louis E. Toth, Michael S. Osofsky, Steven H. Lawrence, Donald U. Gubser, Stuart A. Wolf
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Patent number: 5100866Abstract: A superconducting material and a process for producing a superconducting material comprising a compound oxide represented by the general formula:(Ba, .gamma.).sub.x (.alpha.,.beta.).sub.1 -.sub.x .epsilon..sub.y Cu.sub.1-y O.sub.3-zin which".gamma." represents an element of the IIa group of the periodic table except Ba, and atomic ratio of .gamma. to Ba, being selected in a range between 1% and 90%,".alpha." represents Y or La,".beta." represents an element of the IIIa group of the periodic table but is different from .alpha., an atomic ratio of .beta. to .alpha. being selected in a range between 1 and 90%,".epsilon." represents a metal element of the IIIb group of the periodic table, x, y and z are numbers each satisfies ranges of 0.ltoreq.x.ltoreq.1, 0.ltoreq.y.ltoreq.1, and 0.ltoreq.z.ltoreq.1 respectively, andthe expression of (Ba, .gamma.) and (.alpha.,.beta.) mean that the respective elements occupy predetermined sites in a crystal in a predetermined proportion.Type: GrantFiled: October 26, 1989Date of Patent: March 31, 1992Assignee: Sumitomo Electric Industries Ltd.Inventors: Hideo Itozaki, Saburo Tanaka, Nobuhiko Fujita, Shuji Yazu, Tetsuji Jodai
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Patent number: 5084439Abstract: A high temperature superconductor is provided having meltability. The superconductor has a preferred composition of Tb-R-Ba-Cu-O wherein R is chosen from the group of rare earth metals excluding: Praseudyium; Cerium; and Terbium.Type: GrantFiled: March 17, 1989Date of Patent: January 28, 1992Assignee: The University of ArkansasInventors: Allen M. Hermann, Zhengzhi Sheng
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Patent number: 5011822Abstract: A method for producing uniform mixed metal oxides, such as superconducting mixtures including Y.sub.1 Ba.sub.2 Cu.sub.3 O.sub.7-x, in which such metals are precipitated as their oxalates from alcoholic solutions of the metals as the salts of a carboxylic acid.Type: GrantFiled: January 10, 1989Date of Patent: April 30, 1991Assignee: Allied-Signal Inc.Inventor: Timothy J. Barder
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Patent number: 4983571Abstract: A method for improving the superconducting transition temperature of the MBa.sub.2 Cu.sub.3 O.sub.x where M is selected from the group consisting of Y, Er, Eu, Yb, Dy and Ho and where x is a value of from 6 to 7 ceramic by utilizing specific sequences of heat treating times and temperatures in conjunction with the use of silver oxide in making superconducting devices or wires for ultimate use in motors, generators and electrical circuits.Type: GrantFiled: January 30, 1990Date of Patent: January 8, 1991Assignee: The United States of America as represented by the Secretary of the NavyInventors: A. Srinivasa Rao, Om P. Arora, Louis F. Aprigliano