Abstract: A device for the high pressure densification of superconducting wire from compacted superconductor material or superconductor precursor powder particles, has four hard metal anvils (5, 6, 7, 8) with a total length (L2) parallel to the superconducting wire, the hard metal anvils borne in external independent pressure blocks (9, 10, 11), which are in turn either fixed or connected to high pressure devices, preferably hydraulic presses. At least one of the hard metal anvils is a free moving anvil (6) having clearances of at least 0.01 mm up to 0.2 mm towards the neighboring hard metal anvils (5, 8), so that no wall friction occurs between the free moving anvil and the neighboring anvils. This allows for high critical current densities Jc at reduced pressure applied to the hard metal anvils.

Abstract: A method for producing a superconductive wire, whereby an elongated intermediate element is formed out of an initial element in a deformation step and whereby the superconductive filaments are formed by a final reaction heat treatment, is characterized in that prior to the final reaction heat treatment the filaments in the intermediate element are densified in one or more high pressure densification steps following up the deformation step, said densification steps comprising a simultaneous action of at least four hard surfaces perpendicular to the axis of the elongated intermediate element, building up high pressure P?100 MPa on a part of the intermediate element having an axial length L. This leads to a substantial increase of the critical current density Jc, whereby the anisotropy factor ? is be almost not affected thus enabling production of almost isotropic wires or tapes.

Abstract: This invention relates to a method for producing components with internal architectures, and more particularly, this invention relates to a method for producing structures with microchannels via the use of diffusion bonding of stacked laminates. Specifically, the method involves weakly bonding a stack of laminates forming internal voids and channels with a first generally low uniaxial pressure and first temperature such that bonding at least between the asperites of opposing laminates occurs and pores are isolated in interfacial contact areas, followed by a second generally higher isostatic pressure and second temperature for final bonding. The method thereby allows fabrication of micro-channel devices such as heat exchangers, recuperators, heat-pumps, chemical separators, chemical reactors, fuel processing units, and combustors without limitation on the fin aspect ratio.

Abstract: A method for producing a superconductive wire, whereby an elongated intermediate element is formed out of an initial element in a deformation step and whereby the superconductive filaments are formed by a final reaction heat treatment, is characterized in that prior to the final reaction heat treatment the filaments in the intermediate element are densified in one or more high pressure densification steps following up the deformation step, said densification steps comprising a simultaneous action of at least four hard surfaces perpendicular to the axis of the elongated intermediate element, building up high pressure P?100 MPa on a part of the intermediate element having an axial length L. This leads to a substantial increase of the critical current density Jc, whereby the anisotropy factor F is be almost not affected thus enabling production of almost isotropic wires or tapes.

Abstract: An improved process for the preparation of oxide superconducting rods. The present invention provides a process for the preparation of oxide superconducting rods. The process includes the steps of a cold isopressing process without addition of binder, particularly thin and those based on Ag-added (Bi,Pb)2 Sr2 Ca2 Cu3 O10+x is disclosed.

Abstract: A method for manufacturing a powder-metallurgy processed Nb3Sn superconducting wire is provided. In the method, a sheath made of Nb or a Nb alloy is filled with a raw material powder containing Sn. The sheath filled with the raw material powder is subjected to diameter reduction to form a wire. The wire is heat-treated to form a superconducting phase at the internal surface of the sheath. The raw material powder is prepared by adding a Sn powder to a Cu—Sn alloy powder or a Cu—Sn intermetallic compound powder, and is compacted under isotropic pressure.

Abstract: In the present invention, a superconducting (sc) ceramic filament is enclosed in a silver sheath which is sealed therearound by applying silver powder between the surfaces of said sheath, pressing the surfaces and powder into contact and then applying sufficient heat to fuse them together, which heat is below the melting point of the surfaces and powder and then sintering the so enclosed ceramic filament, which upon cooling, forms a superconductor.

Abstract: A superfine multi-core Nb3Al superconductive wire is produced by getting a Nb3Al superconductive wire ready which was obtained by subjecting a precursor wire having a superfine multi-core structure in which a plurality of Nb/Al complex cores are embedded in Nb, Ta, a Nb based dilute alloy, or a Ta based dilute alloy as the matrix to a rapid heating and quenching treatment comprising rapidly heating to a temperature range near 2,000° C. in 2 seconds, (A) coating the Nb3Al superconductive wire with Cu or Ag as the stabilizing material; then (B) subjecting to a hot isostatic press (HIP) process for 10 minutes or more in a inert gas environment with a pressure of 40 atmospheres or more; and then (C) subjecting heat treatment for 1–200 hours in temperature range of 680–850° C.

Abstract: The inventive method of manufacturing an oxide superconducting wire comprises a step (S1, S2) of preparing a wire formed by covering raw material powder of an oxide superconductor with a metal and a step (S4, S6) of heat-treating the wire in a pressurized atmosphere, and the total pressure of the pressurized atmosphere is at least 1 MPa and less than 50 MPa. Thus, formation of voids between oxide superconducting crystals and blisters of the oxide superconducting wire is suppressed while the partial oxygen pressure can be readily controlled in the heat treatment, whereby the critical current density can be improved.

Abstract: A method for winding on embedded b-zero coil maintains the integrity of superconducting main coil and the b-zero wire during coil winding and during normal operation of a superconducting MRI magnet. The b-zero coil is co-wound with an aluminum overwrap while the aluminum overwrap is being wound onto the superconducting MRI coil. The two-wire geometries are selected such that the height or thickness of the aluminum overwrap is greater than or equal to the height or thickness of the b-zero coil wire. The b-zero coil wire sits in a cavity that is created by adjacent turns.

Abstract: The method of preparing an oxide superconducting wire comprises steps of preparing a wire by coating raw material powder for a Bi—Pb—Sr—Ca—Cu—O based oxide superconductor including a 2223 phase with a metal and heat treating the wire in a pressurized atmosphere containing oxygen in a prescribed partial pressure, and the total pressure of the pressurized atmosphere is at least 0.5 MPa. The pressure heat treatment apparatus comprises a pressure furnace storing and heat treating a target in a pressurized atmosphere, a pressure regulator for measuring the total pressure in the pressure furnace, an oxygen concentration meter for measuring the oxygen concentration in the pressure furnace and a controller for controlling the oxygen partial pressure in the pressure furnace in response to the total pressure measured by the pressure regulator and the oxygen concentration measured by the oxygen concentration meter.

Abstract: A method for increasing the critical temperature, Tc, of a high critical temperature superconducting (HTS) film (104) grown on a substrate (102) and a superconducting structure (100) made using the method. The HTS film has an a-b plane parallel to the surface of the substrate and a c-direction normal to the surface of the substrate. Generally, the method includes providing the substrate, growing the HTS film on the substrate and, after the HTS film has been grown, inducing into the HTS film a residual compressive strain the a-b plane and a residual tensile strain into the c-direction.

Abstract: A novel process of the production and processing of high quality, high Tc BSCCO or (Bi,Pb)SCCO superconductors starts with fabrication of a forming a bundle including a plurality of billets, each billet containing at least one filament comprising a dominant amount of an tetragonal BSCCO phase with selected intermediate phases, and substantially surrounded by a constraining metal. The bundle is thermomechanically consolidated to form a multifilamentary precursor article by applying pressure and heat to the bundle under conditions cooperatively selected to cause interdiffusion of said constraining metal at the interfaces between said metal and said filaments and substantially complete elimination of voids in said bundle, and the consolidation step is completed before any high strain longitudinal deformation is performed on the bundle.

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 niobium-based superconductor is manufactured by establishing multiple niobium components in a billet of a ductile metal, working the composite billet through a series of reduction steps to form the niobium components into elongated elements, each niobium element having a thickness on the order of 1 to 25 microns, surrounding the billet prior to the last reduction step with a porous confining layer of an acid resistant metal, immersing the confined billet in an acid to remove the ductile metal from between the niobium elements while the niobium elements remain confined by said porous layer, exposing the confined mass of niobium elements to a material capable of reacting with Nb to form a superconductor.

Abstract: A superconducting wire having a stacked structure comprising (a) a substrate composed of an electrically conductive material, (b) an oxide superconductor material, and (c) an electrically conductive material which is substantially not reactive with said oxide superconductor material (b), wherein said electrically conductive material (c) is impregnated in said oxide superconductor material (b) by way of heat fusion such that gaps among crystal grains contained in said oxide superconductor material (b) are filled with said electrically conductive material (c). And a process for the production of said superconducting wire.

Abstract: An oxide superconducting wire of an anisotropic oxide superconductor comprises a core part of the wire and a superconducting layer enclosing the core part so that specific crystal axes of the oxide superconductor are oriented toward the core part. A method of producing a wire of an anisotropic oxide superconductor comprises the steps of arranging a metal sheath around a metal rod for forming a core part of the wire and charging powder of the oxide superconductor in a clearance between the metal sheath and the metal rod for preparing a composite material, and plastically working the composite material so that the metal sheath is larger in reduction of area than the metal rod.

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: A method of preparing wires or tapes including Bi-2223 superconductor material by providing oxide and carbonate sources of Bi, Sr, Ca, Cu and Pb, milling the material for a time not to exceed about 30 minutes but preferably not greater than 20 minutes to produce a homogeneous mixture. Then heat treating by calcining the milled mixture at a temperature of at least about 830° C. for a time not less than about 12 hours, followed by at least one additional milling for a time not to exceed about 20 minutes and one additional heat treatment, to produce an oxide powder having an average diameter in the 4 to 5 micron range. Then a silver or silver alloy tube is filled with the oxide powder, and shape formed into a rectangular tape. Then alternately thermally treating and mechanically working the tube filled with oxide powder by heating the filled tube to an elevated temperature of about 835° C. to 840° C. and reducing the diameter of the tube, repeating the thermal and mechanical treatment.

Abstract: The invention relates to a process for producing a shaped body, in which a mixture of oxidic starting powders or a superconducting material, which comprises at least 30% by volume of platelet-shaped primary particles and has such a composition that a high-temperature superconducting material is formed on later, suitable thermal treatment, is comminuted by milling, shearing and/or rolling in such a way that the comminuted powder has a powder particle size distribution having a d90 of ≦20 &mgr;m, and in which the powders which have been comminuted in this way are isostatically compacted by the dry bag method.

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: The fabrication of superconducting wires and rods having desired and consistent electrical and mechanical properties, in particular those based on Yttrium Barium Copper Oxide (YBCO) and Bismuth Strontium Calcium Copper Oxide (BSCCO), is disclosed. The first fabrication step is to form an extrudable paste by mixing YBCO or BSCCO superconducting powder with a set of organic additives, which include binder, plasticizer, lubricant, dispersant, and a solvent. The following additional steps are performed on both YBCO and BSCCO based wires or rods: (i) using a piston extruder to extrude the superconducting wire or rod; (ii) drying the wire or rod to remove the solvent; and (iii) subjecting the wire or rod to a binder burn-out treatment to remove the remaining organic additives. In addition, YBCO wires and rods also require a sintering step, while BSCCO wires and rods also require cold isostatic pressing and heat treatment steps.

Abstract: A novel process of the production and processing of high quality, high T.sub.c BSCCO or (Bi,Pb)SCCO superconductors starts with fabrication of a forming a bundle including a plurality of billets, each billet containing at least one filament comprising a dominant amount of an tetragonal BSCCO phase with selected intermediate phases, and substantially surrounded by a constraining metal. The bundle is thermomechanically consolidated to form a multifilamentary precursor article by applying pressure and heat to the bundle under conditions cooperatively selected to cause interdiffusion of said constraining metal at the interfaces between said metal and said filaments and substantially complete elimination of voids in said bundle, and the consolidation step is completed before any high strain longitudinal deformation is performed on the bundle.

Abstract: A layered oxide superconductor prepared by depositing a superconductor precursor powder on a continuous length of a first substrate ribbon. A continuous length of a second substrate ribbon is overlaid on the first substrate ribbon. Sufficient pressure is applied to form a bound layered superconductor precursor powder between the first substrate ribbon and the second substrate ribbon. The layered superconductor precursor is then heat treated to establish the oxide superconducting phase. The layered oxide superconductor has a smooth interface between the substrate and the oxide superconductor.

Abstract: A (BiPb).sub.2 Sr.sub.2 Ca.sub.2 Cu.sub.3 O.sub.x (Bi223) superconductor with high J.sub.c, phase purity, density and mechanical strength is formed from Bi2223 powder which is synthesized from a mixture of Bi.sub.2 O.sub.3, PbO, SrCO.sub.3, CaCo.sub.3 and CuO. The mixture is milled, then dried and calcined to synthesize the Bi2223 powder with the desired phase purity. The calcination is performed by heating the dried mixture for 50 hours at 840.degree. C. The partially synthesized powder is then milled for 1-4 hours before calcining further for another 50 hours at 855.degree. C. to complete the synthesis. After calcination, the Bi2223 powder is cold pressed to a predetermined density and sinter forged under controlled temperature and time to form a Bi2223 superconductor with the desired superconducting properties.

Abstract: The present invention is directed to a process for producing high temperature superconducting ceramic materials. More particularly, the present invention is directed to a process that enhances the densification of Bi.sub.1.8 Pb.sub.0.4 Sr.sub.2 Ca.sub.2 Cu.sub.3 O.sub.10 "BSCCO" ceramics.

Abstract: Enhanced flux pinning in superconductors is achieved by embedding carbon nanotubes into a superconducting matrix. The carbon nanotubes simulate the structure, size and shape of heavy ion induced columnar defects in a superconductor such as Bi.sub.2 Sr.sub.2 CaCu.sub.2 O.sub.8+x. The nanotubes survive at treatment temperatures of up to approximately 800.degree. C. both in oxygen containing and in inert atmospheres. The superconducting matrix with nanotubes is heat treated at a lower temperature than the temperature used to treat the best case pure superconductor material.

Abstract: A method of producing a high temperature long length coil of superconductor wire or tape having improved critical current densities by utilizing an in-line pressing operation to heal the microcracks in the tape or wire which were introduced in rolling and coiling operations. The material can be Bismuth-2223, Bismuth 2212, Thallium-1234 or any other high temperature superconducting material. In the case of the Bismuth-2223, an improved "powder-in-tube" processing operation is provided to utilize excess bismuth, calcium, and copper in the initial composition material, and forming a partially developed Bi-2223 phase in the precursor powder introduced into the silver tubes. The final product has a 90-100% Bi-2223 phase with fine dispersions of secondary phases, to provide improved flux pinning thereby improving the critical current density of the material.

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.

Abstract: Composite bulk superconducting materials having desirable physical, measured transport current density and high T.sub.c superconducting characteristics are provided which comprise a first matrix of superconducting ceramic oxide crystalline grains with a second matrix of elemental metal (gold, silver, palladium and tin) situated within the interstices between the crystalline grains. Preferably, each matrix is a continuous phase within the composite material, with the ceramic oxide preferably being present at a level of at least about 80% by weight, whereas the elemental metal is present at a level of up to about 20% by weight. In fabrication procedures, a precursor superconducting ceramic oxide is first prepared and reduced to a fine powder size; this is mixed with powdered elemental metal, and the mixture is compressed using high compaction pressures on the order of 14 tons/cm.sup.2 or greater to form a body, which is then sintered to yield the composite.

Abstract: In order to prevent inflation of a metallic coating during heat treatment so that no ununiformity is caused in the critical current density in a method of preparing an oxide superconducting wire which is obtained by heat treating and sintering metal-coated raw material powder for an oxide superconductor, raw material powder (5) for an oxide superconductor is filled up in a metal billet (1), which in turn is degassed and sealed in the degassed state, elongated with application of hydrostatic extrusion, and then heat treated.

Abstract: A superconductive article is made by inserting a rigid mandrel into an internal cavity of a first metallic tube, said tube having an interior surface and an exterior surface, said interior surface defining the interior cavity, forming a layer of a superconductive material or superconductive precursor upon the exterior surface of said first metallic tube, machining the layer of superconductive material or superconductive precursor to a predetermined diameter to form an intermediate article configured for insertion into a second metallic tube having an interior diameter corresponding to the predetermined diameter, inserting the machined intermediate article into a second metallic tube having an internal diameter corresponding to the predetermined diameter of the intermediate article to form a composite intermediate article, reducing or ironing the composite intermediate article to a predetermined cross-sectional diameter, and sintering the reduced or ironed composite intermediate article at temperatures and for

Abstract: High-Tc superconducting ceramic oxide products and macroscopic and microscopic methods for making such high-Tc superconducting products. Completely sealed high-Tc superconducting ceramic oxide products are made by a macroscopic process including the steps of pressing a superconducting ceramic oxide powder into a hollow body of a material inert to oxygen; heat treating the superconducting ceramic oxide powder packed body under conditions sufficient to sinter the ceramic oxide powder; and then sealing any openings of the body. Optionally, a waveform or multiple pulses of alternate magnetic field can be applied during the heat treatment.

Abstract: A superconductor wire comprising an inner core and an outer ring covering the core, wherein one of the inner core and the outer ring comprises a sintered silver powder and the other of the inner core and the outer ring on the core comprises a sintered oxide superconductor powder.

Abstract: In order to prevent inflation of a metallic coating during heat treatment so that no ununiformity is caused in the critical current density in a method of preparing an oxide superconducting wire which is obtained by heat treating and sintering metal-coated raw material powder for an oxide superconductor, raw material powder (5) for an oxide superconductor is filled up in a metal billet (1), which in turn is degassed and sealed in the degassed state, elongated with application of hydrostatic extrusion, and then heat treated.