Abstract: A process for manufacturing superconducting magnetic coils from strain-tolerant, superconducting multi-filament composite conductors is described. The method involves winding the precursor to a multi-filament composite conductor and an insulating material or its precursor around a mandrel in order to form a coil, and then exposing the coil to high temperatures and an oxidizing environment. The insulating material or its precursor is chosen to permit exposure of the superconductor precursor filaments to the oxidizing environment, and to encase the matrix-forming material enclosing the filaments, which is reversibly weakened during processing.

Abstract: An energy storage device includes a first electrode comprising a first material and a second electrode comprising a second material, at least a portion of the first and second materials forming an interpenetrating network when dispersed in an electrolyte, the electrolyte, the first material and the second material are selected so that the first and second materials exert a repelling force on each other when combined. An electrochemical device, includes a first electrode in electrical communication with a first current collector; a second electrode in electrical communication with a second current collector; and an ionically conductive medium in ionic contact with said first and second electrodes, wherein at least a portion of the first and second electrodes form an interpenetrating network and wherein at least one of the first and second electrodes comprises an electrode structure providing two or more pathways to its current collector.

Abstract: A method of making an oxide superconductor article includes subjecting an oxide superconductor precursor to a texturing operation to orient grains of the oxide superconductor precursor to obtain a highly textured precursor; and converting the textured oxide superconducting precursor into an oxide superconductor, while simultaneously applying a force to the precursor which at least matches the expansion force experienced by the precursor during phase conversion to the oxide superconductor. The density and the degree of texture of the oxide superconductor precursor are retained during phase conversion. The constraining force may be applied isostatically.

Abstract: A method of making an oxide superconductor article includes converting an oxide superconducting precursor into an oxide superconductor by thermo-mechanical processing using intermediate rolling deformation and heat treatment (including liquid-phase sintering and low temperature baking) and applying an additional heat treatment after the material is fully processed (including optional liquid-phase sintering and low temperature baking) to decompose any secondary phase remaining at the grain boundaries and to promote diffusion of the secondary phase into the oxide grain, where they form 2223 phase. The material has a better superconducting grain connectivity and improved superconducting transport property.

Abstract: A method of making a high density Mg—B superconducting article includes providing a packed powder sheath, said powder comprising a source of magnesium and boron, subjecting the packed powder sheath to a symmetric deformation, said deformation selected to elongate the packed powder sheath to form a wire while retaining the free flow of particles within the powder core, subjecting the wire to high reduction rolling, said high reduction rolling selected to reduce the wire thickness by 40 to 95% and heating the rolled article to improve the superconducting properties of the article. A superconducting article comprised of one or more elongated metal matrix regions containing one or more embedded elongated superconducting Mg—B regions running the full length of the article is disclosed, wherein the superconducting Mg—B regions have a density greater than 95 % of the theoretical density, and a transition temperature in zero field of 30 K.

Abstract: A reduced coefficient of friction, preferably created by ideal lubrication conditions, may advantageously be employed in the breakdown deformation of a precursor to a multifilamentary superconducting composite, particularly in combination with one or more high reduction breakdown drafts, to improve composite homogeneity and significantly increase the range of deformation conditions over which dimensional tolerances and Je may be optimized. Precursor composites made by this method exhibit reduced microhardness variability and fewer and less serious transverse filament defects than composites made by prior art methods. The method comprises the steps of: first, providing a precursor article comprising a metal matrix surrounding a plurality of filaments extending along the length of the article and comprising precursors to a desired superconducting ceramic; next, roll working the precursor article during a breakdown stage at a predetermined pressure and a coefficient of friction less than about 0.

Abstract: A modified powder-in-tube process produces a superconductor wire having a significantly greater current density than will a superconductor wire of the same nominal superconductor composition produced using conventional draw-swage-extrude-roll deformation. In the process disclosed, a superconductor precursor is placed within a ductile tube, the tube with the powder therein is then deformed into a cross-section substantially corresponding to that of the end product, and the deformed tube is then subject to a plurality of heat treatments to convert the precursor into the desired superconducting ceramic oxide phase. Before the last of the heat treatments, the tube is isostatically pressed to densify and texture the superconductor precursor oxide in the tube.

Abstract: Processes for the fabrication of MgB2 powder and wires are provided. Powders are produced by mechanically alloying magnesium- and boron-containing precursors under controlled conditions to avoid secondary phase and impurity formation. Powders are also prepared by vapor phase reaction of volatile magnesium- and boron-containing precursors. Wires, tapes, films and coatings are provided.

Abstract: This invention relates to a practical superconducting conductor based upon biaxially textured high temperature superconducting coatings. In particular, methods for producing flexible and bend strain-resistant articles and articles produced in accordance therewith are described which provide improved current sharing, lower hysteretic losses under alternating current conditions, enhanced electrical and thermal stability and improved mechanical properties between otherwise isolated films in a coated high temperature superconducting (HTS) wire. Multilayered materials including operational material which is sensitive to bend strain can be constructed, in which the bend strain in the region in which such operational material is located is minimized. The invention also provides a means for splicing coated tape segments and for termination of coated tape stack ups or conductor elements.

Abstract: A multifilamentary superconductor composite having a high fill factor is formed from a plurality of stacked monofilament precursor elements, each of which includes a low density superconductor precursor monofilament. The precursor elements all have substantially the same dimensions and characteristics, and are stacked in a rectilinear configuration and consolidated to provide a multifilamentary precursor composite. The composite is thereafter thermomechanically processed to provide a superconductor composite in which each monofilament is less than about 50 microns thick.

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 defied 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.

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)≧3.5×1010 exp(−32,000/T+273) and an upper bound defined by the equation, PO2(upper)≦1.1×1012 exp(−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.

Abstract: The invention features high performing composite superconducting oxide articles that can be produced from OPIT precursors substantially without poisoning the superconductor. In general, the superconducting oxide is substantially surrounded by a matrix material. The matrix material contains a first constraining material including a noble metal and a second metal. The second metal is a relatively reducing metal which lowers the overall oxygen activity of the matrix material and the article at a precursor process point prior to oxidation of the second metal. The second metal is substantially converted to a metal oxide dispersed in the matrix during or prior to a first phase conversion heat treatment but after formation of the composite, creating an ODS matrix.

Abstract: A novel process of the production and processing of high quality, high Tc (Bi,Pb)SCCO superconductors starts with fabrication of a precursor article including selected intermediate phases with desired chemical and structural properties. The precursor fabrication includes introducing the reacted mixture having a dominant amount of the tetragonal BSCCO phase into a metal sheath, and sealing the reacted mixture within said sheath, heating the mixture at a second selected processing temperature in an inert atmosphere with a second selected oxygen partial pressure for a second selected time period, the second processing temperature and the second oxygen partial pressure being cooperatively selected to form a dominant amount of an orthorhombic BSCCO phase in the reacted mixture.

Abstract: The invention provides a multifilamentary superconducting composite article comprising multiple substantially electrically decoupled domains, each including one or more fine, preferably twisted filaments of a desired superconducting oxide material. In a preferred embodiment, the article comprises a matrix, which substantially comprises a noble metal, a conductive jacketing layer surrounding the matrix, a plurality of discrete filament decoupling layers, each comprising an insulating material, disposed within the matrix to separate the matrix into a plurality of substantially electrically decoupled domains; a plurality of filaments, each comprising a desired superconducting oxide, which are disposed within and essentially encapsulated by the matrix and chemically isolated thereby from the decoupling layers, each of the electrically decoupled domains containing at least one filament.

Abstract: A reduced coefficient of friction, preferably created by ideal lubrication conditions, may advantageously be employed in the breakdown deformation of a precursor to a multifilamentary superconducting composite, particularly in combination with one or more high reduction breakdown drafts, to improve composite homogeneity and significantly increase the range of deformation conditions over which dimensional tolerances and Je may be optimized. Precursor composites made by this method exhibit reduced microhardness variability and fewer and less serious transverse filament defects than composites made by prior art methods. The method comprises the steps of: first, providing a precursor article comprising a metal matrix surrounding a plurality of filaments extending along the length of the article and comprising precursors to a desired superconducting ceramic; next, roll working the precursor article during a breakdown stage at a predetermined pressure and a coefficient of friction less than about 0.

Abstract: A multifilamentary superconductor composite having a high fill factor is formed from a plurality of stacked monofilament precursor elements, each of which includes a low density superconductor precursor monofilament. The precursor elements all have substantially the same dimensions and characteristics, and are stacked in a rectilinear configuration and consolidated to provide a multifilamentary precursor composite. The composite is thereafter thermomechanically processed to provide a superconductor composite in which each monofilament is less than about 50 microns thick.

Abstract: A method of texturing a multifilamentary article having filaments comprising a desired oxide superconductor or its precursors by torsionally deforming the article is provided. The texturing is induced by applying a torsional strain which is at least about 0.3 and preferably at least about 0.6 at the surface of the article, but less than the strain which would cause failure of the composite. High performance multifilamentary superconducting composite articles having a plurality of low aspect ratio, twisted filaments with substantially uniform twist pitches in the range of about 1.00 inch to 0.01 inch (25 to 0.25 mm), each comprising a textured desired superconducting oxide material, may be obtained using this texturing method. If tighter twist pitches are desired, the article may be heat treated or annealed and the strain repeated as many times as necessary to obtain the desired twist pitch.

Abstract: The present invention provides a (Bi,Pb)SCCO-2223 oxide superconductor composite which exhibits improved critical current density and critical current density retention in the presence of magnetic fields. Retention of critical current density in 0.1 T fields (77 K, ⊥ ab plane) of greater than 35% is disclosed. Significant improvements in oxide superconductor wire current carrying capacity in a magnetic field are obtained by subjecting the oxide superconductor composite to a post-processing heat treatment which reduces the amount of lead in the (Bi,Pb)SCCO-2223 phase and forms a lead-rich non-superconducting phase. The heat treatment is carried out under conditions which localize the lead-rich phase at high energy sites in the composite.

Abstract: The invention features high performing composite superconducting oxide articles that can be produced from OPIT precursors substantially without poisoning the superconductor. In general, the superconducting oxide is substantially surrounded by a matrix material. The matrix material contains a first constraining material including a noble metal and a second metal. The second metal is a relatively reducing metal which lowers the overall oxygen activity of the matrix material and the article at a precursor process point prior to oxidation of the second metal. The second metal is substantially converted to a metal oxide dispersed in the matrix during or prior to a first phase conversion heat treatment but after formation of the composite, creating an ODS matrix.