Abstract: A superconductor having at least one Hg—M—Cu—O (M=Ba, Sr and/or Ca) superconducting film provided on a substrate and having a thickness of between 300 Å to 950 Å. The superconductor may be prepared by forming, on a substrate, a precursor laminate composed of a first, M—Cu—O film and a second, Hg—O film. The precursor laminate film-bearing substrate is placed in a closed vacuum chamber together with a first pellet of HgO, MO and CuO and a second pellet of MO and CuO. The contents in the chamber are heated to form, on the substrate, a superconducting Hg—M—Cu—O film. The thickness of the first M—Cu—O film of the precursor is controlled so that the thickness of the superconducting Hg—M—Cu—O film is in the range of between 300 Å to 950 Å.

Abstract: A method is described to prepare a highly textured oxide superconductor article in a single deformation-sinter process. A precursor article including a plurality of filaments comprising a precursor oxide having a dominant amount of a tetragonal BSCCO 2212 phase and a constraining member substantially surrounding each of the filaments is provided. Each of the filaments extends along the length of the article. The oxide article is subjected to a heat treatment at an oxygen partial pressure and temperature selected to convert a tetragonal BSCCO 2212 oxide into an orthorhombic BSCCO 2212 oxide and, thereafter, roll worked in a high reduction draft in a range of about 40% to 95% in thickness so that the filaments have a constraining dimension is substantially equivalent to a longest dimension of the oxide superconductor grains. The rolled article is sintered to obtain a BSCCO 2223 oxide superconductor.

Abstract: There is disclosed a continuous process for the formation of a superconducting wire utilizing magnesium diboride powder. The process provides a long length, low cost strand of superconducting wire which can be used in a monofilament or multifilament form.

Abstract: By a method for constructing a superconducting multiphase cable comprising N phases, the phases are divided into n groups with N phases in each group, all the groups have a common screen. The individual groups may be geomtrically formed with coaxial or flat phases. The individual phases in each group may further be divided into individual conductors such as tapes. The insulation between the individual conductors in the groups may be separately insulated from each other or have a common insulation. In a particularly appropriate embodiment, the number of groups is 1 and implemented with a flat or concentric geometry. In this way, a compact superconducting power cable is provided, which is relatively inexpensive in production and has few working operations while maintaining good electrical properties.

Abstract: A method is described to prepare a highly textured oxide superconductor article in a single deformation-sinter process. A precursor article including a plurality of filaments comprising a precursor oxide having a dominant amount of a tetragonal BSCCO 2212 phase and a constraining member substantially surrounding each of the filaments is provided. Each of the filaments extends along the length of the article. The oxide article is subjected to a heat treatment at an oxygen partial pressure and temperature selected to convert a tetragonal BSCCO 2212 oxide into an orthorhombic BSCCO 2212 oxide and, thereafter, roll worked in a high reduction draft in a range of about 40% to 95% in thickness so that the filaments have a constraining dimension is substantially equivalent to a longest dimension of the oxide superconductor grains. The rolled article is sintered to obtain a BSCCO 2223 oxide superconductor.

Abstract: An Oxide Precursor Powder from the Pb—Bi—Sr—Ca—Cu—O 2223 System can be produced by heat treating powder, produced using the Spray Pyrolysis Process as described in: GB2210605 or EP0681989 between 700° C. and 850° C. in an atmosphere containing between 0.1% and 21% O2. Heat Treatment of the pyrolysis powder under controlled conditions produces a powder with a particular phase composition, that is highly homogeneous and has a small particle size distribution, that is inherently more reactive than powders heat treated in the same way but produced using other processes.

Abstract: The present invention relates to a method and an apparatus for manufacturing keystone type superconducting compacted stranded wires. In manufacturing the keystone type superconducting compacted stranded wires, a large number of superconducting wires are stranded to form stranded wires, which are then roll-formed. The method and apparatus are configured so that, in the roll-forming, one side of the compacted stranded wires, which is thinner than the other side thereof after being roll-formed, comes into contact with one flat roll before the other side of the compacted stranded wires comes into contact with another flat roll. The method and apparatus are provided as another configuration wherein one flat roll to contact with the compacted stranded wires to be thicker is smaller in diameter than another flat roll to contact with the compacted stranded wires to be thinner.

Abstract: A method for fabricating a cable-in-conduit-conductor for use in superconductor application is described. The system utilizes a work surface with drum means provided at each end. A superconductor cable is fed from a supply source at one end. After the cable is pulled through a tube on the work surface, the leading edge of the cable is bent around one of the drums and returned to the opposite end of the table. This naked length of cable is once again bent around one of the drums and then pulled through another tube on the table. This process is repeated until an acceptable length of superconductor cable is present. Tension means are used in conjunction with a tube mill which compresses the tube-cable combination into a viable cable-in-conduit conductor (CICC). Notably, as this tension-compression is occurring, the naked lengths of cable are eliminated and each separate tube section is joined together to create a uniform CICC.

Abstract: A superconductor having at least one Hg-M-Cu—O (M=Ba, Sr and/or Ca) superconducting film provided on a substrate and having a thickness of between 300 Å to 950 Å. The superconductor may be prepared by forming, on a substrate, a precursor laminate composed of a first, M-Cu—O film and a second, Hg—O film. The precursor laminate film-bearing substrate is placed in a closed vacuum chamber together with a first pellet of HgO, MO and CuO and a second pellet of MO and CuO. The contents in the chamber are heated to form, on the substrate, a superconducting Hg-M-Cu—O film. The thickness of the first M-Cu—O film of the precursor is controlled so that the thickness of the superconducting Hg-M-Cu—O film is in the range of between 300 Å to 950 Å.

Abstract: A flexible interconnect cable is manufactured by a method that includes providing a core, and wrapping a conductive shield element about the core. An insulating sheath layer is extruded about the core to encompass the shield element, and a multi-wire cable component having ribbonized ends and detached intermediate portions is connected to an end of the core. The core is removed from the sheath to insert the cable component into the sheath. The resulting assembly has intermediate portions of the cable component that are loosely received within the shield and sheath.

Abstract: A method of forming a winding support structure for use with a superconducting rotor wherein the method comprises providing an inner support ring, arranging an outer support ring around the inner support ring, coupling first and second support blocks to the outer support ring and coupling a lamination to the first and second support blocks. A slot is defined between the support blocks and between the outer support ring and the lamination to receive a portion of a winding. An RTV fills any clearance space in the slot.

Abstract: According to the inventive method for producing a superconductive coil, a shaped body consisting of a material which is superconductive or which becomes superconductive upon subsequent heat treatment is coated with reinforcement agents and is given the geometric shape of the future coil. The invention also relates to a superconductive coil produced according to this method. Said inventive superconductive coil has low alternating current loss and consists of a highly textured superconductive material, and is oriented in such a way that the platelet levels are directly considerably in the direction of the course of the coil. The coil is formed from a superconductive solid part.

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 superconducting magnetic resonance imaging magnet assembly is provided. The assembly includes an axial imaging bore to receive patients and a coil housing surrounding the axial bore. A main magnet coil assembly is disposed within the housing. The main magnet coil assembly includes a plurality of main magnet coils to produce a magnetic field. At least three pairs of superconductive coils are provided. In one aspect, each of the coils in at least one of the pairs comprises a superconductor wire carrying an electric current in a direction opposite to the direction of current carried by the coils of another of the superconductive pairs. The superconductor wire comprises a superconductor core and a stabilizer having a channel. The wire is wound so that the channel has a radially outward facing opening.

Abstract: Electrical connection of superconducting lines can be achieved by using a low-melting point metal, by mechanical contact of superconducting lines or by welding. According to these methods, however, critical current and critical magnetic field at the connection point are low, and stable connection in a superconducting state has been difficult. The present invention solves these problems and provides a structure and method for connecting superconducting lines. The present invention provides high-performance, high-stability connection of superconducting lines through magnesium diboride (MgB2) powder arranged between superconducting lines.

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 superconductor filter is stored in a hermetic filter case so that electrical connection can be provided between the superconductor filter and the outside of the hermetic filter case. The hermetic filter case is stored in a hermetic outer case so that electrical connection can be provided between the superconductor filter and the outside of the hermetic outer case and so that air/gas flow through pipes can be implemented between the inside of the hermetic filter case and the outside of the hermetic outer case. The hermetic filter case and the hermetic outer case are evacuated into vacuum, and the superconductor filter is cooled below its critical temperature. After the superconducting state of the superconductor filter could be observed, gas that does not deteriorate or react with the superconductor filter is gradually packed in the hermetic filter case and thereby the dielectric constant around the superconductor filter is raised from the dielectric constant of vacuum.

Abstract: A superconductor having at least one Hg—M—Cu—O (M=Ba, Sr and/or Ca) superconducting film provided on a substrate and having a thickness of between 300 Å to 950 Å. The superconductor may be prepared by forming, on a substrate, a precursor laminate composed of a first, M—Cu—O film and a second, Hg—O film. The precursor laminate film-bearing substrate is placed in a closed vacuum chamber together with a first pellet of HgO, MO and CuO and a second pellet of MO and CuO. The contents in the chamber are heated to form, on the substrate, a superconducting Hg—M—Cu—O film. The thickness of the first M—Cu—O film of the precursor is controlled so that the thickness of the superconducting Hg—M—Cu—O film is in the range of between 300 Å to 950 Å.

Abstract: A manufacturing method for a superconducting wire which is a fine line made of an oxide superconductor, including the steps of forming the fine line by drawing a metal pipe filled with materials for the oxide superconductor, causing the materials to react to produce the oxide superconductor, heating the metal pipe at a temperature which is higher than the melting point of the metal material constituting the metal pipe.

Abstract: It is an object to provide a process for producing a superconducting wire without defects, such as deterioration of characteristics and deformation, in which a superconducting wire having a length of 1 km or more and a high critical electric current density is easily subjected to heat treatment. The first invention comprises a step of inserting a metallic sheath wire, which is formed by filling a superconducting material in a metallic sheath, into a metallic tube having an inner diameter larger than an outer diameter or a width of the metallic sheath wire; and a step of conducting heat treatment under such a condition in that the superconducting wire is wound to overlap a cylindrical fixture to prevent contact with each other while controlling the interior of the metallic tube. The second invention uses a ceramic board on the heat treatment of a pancake formed by winding the metallic sheath wire on a core.

Abstract: A superconducting very high field magnet coil with several solenoidal multi-layer coil sections which are wound in layers onto a hollow cylindrical support body (3) about a common central axis a, and which are electrically connected in series to carry a current in excess of 100 A is characterized in that the radially innermost coil section (1) comprises superconducting wire (2) which contains oxidic, high temperature superconductor (HTS) material, wherein the layers of the radially innermost coil section (1) are helically wound such that there is a free axial space between the walls, which is then sealed.

Abstract: The cross section of a wire is round and is composed of several units, each consisting of tape-like superconductors laminated in an approximately rhombic shape, which are arranged such that they form a hexagon as a whole. Oxide superconducting tape wires each consisting of a plurality of oxide superconducting filaments are arranged in rotational symmetry to a core. The oxide superconducting filaments have the cross section such that the average thickness is 3 to 20 &mgr;m and the average aspect ratio is larger than 2 and smaller than 10. A step of arranging the oxide superconducting tape-like wires in rotational symmetry is accomplished when the multi-core tape-like wires are packed in a third metal pipe which becomes a metal sheath later. Since the multi-core tape wires having oxide superconducting filaments are arranged in rotational symmetry, the oxide superconductor in the oxide superconducting filaments permits its c axis to orient in various directions.

Abstract: An aqueous solution of mixed metal acetate including one kind or more of element selected from lanthanide series and yttrium, barium and copper is mixed with trifluoroacetic acid to prepare a solution of mixed metal trifluoroacetate. From a solution of mixed metal trifluoroacetate obtained thus, purified mixed metal trifluoroacetate of which total content of water and acetic acid is 2% by weight or less is prepared. With purified mixed metal trifluoroacetate, an oxide superconductor of excellent performance may be prepared.

Abstract: The present invention is for a compact superconducting power transmission cable operating at distribution level voltages. The superconducting cable is a conductor with a number of tapes assembled into a subconductor. These conductors are then mounted co-planarly in an elongated dielectric to produce a 3-phase cable. The arrangement increases the magnetic field parallel to the tapes thereby reducing ac losses.

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 provides 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 filed can be applied during the heat treatment.

Abstract: A method for producing a high-Tc superconductor having a strip shape and having at least one superconductive conductor core by forming a conductor initial product and annealing. The forming is in this case intended to include at least two flattening steps. A flattening step which follows a preceding flattening step is intended to result in the percentage thickness reduction in the cross section of the at least one conductor core being greater than that from the preceding flattening step. The strip conductor produced in this way advantageously has a plurality of conductor cores that are embedded in a Ag material and are composed of a bi-cuprate.

Abstract: The present invention provides a generic method of preparing a metal matrix composite with a textured compound. A “roller-skate” structure starting powder with a mixture of plate-like particles and smaller particles provides better flow compatibility, higher packing density, better densification and texture formation in preparing a metal matrix composite with a textured compound. In particular, the invention provides a method of preparing a textured superconducting composite wire with an improved critical current density.

Abstract: A method and fixture for filled billet packing wherein an entire pack is built up in a single step. Substantially even lateral forces are applied to wires and other elongated members within the billet by inserting filler rods at one or more places along the periphery of the pack.

Abstract: This invention provides a production method of Nb3Al superconducting multifilamentary wire based on rapid-heating, quenching and transformation method, capable of producing a high-performance Nb3Al superconducting multifilamentary wire by improving critical temperature thereof, upper critical field and critical current density. Upon a first stage heat treatment of beating a composite, in which bcc phase Nb—Al supersaturated solid solution is dispersed in Nb matrix, the bcc phase Nb—Al supersaturated solid solution ordered in temperature rise process is made disordered at an initial phase thereof and a non-reacting portion located adjacent is heated using a reaction heat generated when transforming this disordered bcc phase to A15 phase. Then, disordering of the bcc phase is promoted while propagating a high-temperature transformation region so as to automatically progress high-temperature beat treatment.

Abstract: Methods for implementing production of an oxide superconductor joined member, excellent in electric current transmission performance, without a need of going through particularly complex steps, are provided. When joining together oxide superconductors by use of a solder composed of an oxide superconducting material, a finally solidified portion of the solder is positioned in a region where a transmission path of electric current flowing between oxide superconductor base materials as joined together is not obstructed by, for example, disposing the solder on a face of the oxide superconductor base materials, other than butting surfaces of the oxide superconductor base materials, so as to straddle both the base materials like bridge-building. Current flow is also not obstructed by, for example, shaping junction faces of the oxide superconductor base materials such that at least portions of the butting surfaces thereof are in the shape of sloped open faces, parting from each other.

Abstract: An system and method for fabricating a cable-in-conduit-conductor for use in superconductor application is described. The system utilizes a work surface with drum means provided at each end. A superconductor cable is fed from a supply source at one end. After the cable is pulled through a tube on the work surface, the leading edge of the cable is bent around one of the drums and returned to the opposite end of the table. This naked length of cable is once again bent around one of the drums and then pulled through another tube on the table. This process is repeated until an acceptable length of superconductor cable is present. Tension means are used in conjunction with a tube mill which compresses the tube-cable combination into a viable cable-in-conduit conductor (CICC). Notably, as this tension-compression is occurring, the naked lengths of cable are eliminated and each separate tube section is joined together to create a uniform CICC.

Abstract: A method is provided of designing a magnetic resonance imaging magnet. At least one correction coil is positioned about the axial bore of the magnet which receives patients. The correction coil is used in the design process to reduce lower order harmonics generated by the magnet. Homogeneity of the magnetic field is thereby improved at selected volumes around the magnet.

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 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 or a high temperature liquid metal 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 cable includes a core material, conductor layers formed by means of helically winding superconducting wires around the core material, electrically insulating layers, and magnetic shielding layers formed by means of helically winding superconducting wires around each of the electrically shielding layers. The superconducting wire is wound at the shortest pitch on the outermost conductor layer and is wound at the longest pitch on the outermost magnetic shielding layer.

Abstract: The diameter of a first metal tube charged with raw material powder is reduced for obtaining an elementary wire. A plurality of such elementary wires are charged into a second metal tube, which in turn is reduced in diameter for obtaining a round first wire having a plurality of first filaments. The first wire is uniaxially compressed thereby obtaining a tape-like second wire having a plurality of second filaments. The second wire is heat treated thereby obtaining an oxide superconducting wire including a plurality of superconductor filaments. The maximum grain size of the raw material powder is smaller than the minor diameter of the first or second filaments.

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: Powder of not more than 1 &mgr;m in mean particle diameter is prepared to contain a mixture of superconducting phases mainly composed of 2212 phases of Bi—Sr—Ca—Cu or (Bi, Pb)—Sr—Ca—Cu and non-superconducting phases which is obtained by calcining and pulverizing raw material powder at least once, this powder is heat treated at a high temperature and thereafter coated with a metal to prepare a round wire by deformation processing, thereafter a tape type or flat type wire is prepared by deformation processing, then the wire is heat treated under conditions for allowing phase transformation of the 2212 phases of main superconducting phases to 2223 phases with facilitation of grain growth, thereafter the as-formed 2223 phases are highly densified by deformation processing or pressurization, and the wire is again heat treated so that the 2223 phases are strongly bonded with each other and the non-superconducting phases are finely dispersed.

Abstract: In order to obtain a superconducting wire containing an oxide superconductor, whose critical current density is not much reduced upon application of bending, a plurality of strands 3, comprising oxide superconductors 1 covered with first metal sheaths 2, are filled into a second metal sheath 4, and deformation processing is performed to sectionally apply a compressive load to the second metal sheath, so that the thickness of the oxide superconductor 1 contained in each strand 3 is not more than 5% of the overall thickness of the superconducting wire 6.

Abstract: A reinforced superconducting coil and method for the reinforcement of such coil utilizing composite superconducting wires clad with high-strength material are disclosed.

Abstract: A new process for making a neodymium gallate (NGO) surface layer on the inside surface of a protective outer sheath of nickel surrounding a core of yttrium-based copper oxide (YBCO) superconductor material permits manufacture of very high performance superconducting wire and tape. The NGO surface layer acts as a diffusion barrier to prevent diffusion of nickel into the YBCO during high temperature melt-processing. The NGO is applied, preferably by slurry casting, to a flat strip of solid nickel and then sintered at temperatures above about 1000° C. The sintering binds the NGO to the nickel strip and fixes it so that it will not react chemically with the YBCO during later melt-processing. The nickel strip and NGO diffusion barrier layer are next rolled into a trough and YBCO ceramic powder inserted inside the trough. The trough is then further rolled into a tube leaving an open seam for oxygen to penetrate during the oxygen anneal procedure of melt-processing.

Abstract: The present invention is for a compact superconducting power transmission cable operating at distribution level voltages. The superconducting cable is a conductor with a number of tapes assembled into a subconductor. These conductors are then mounted co-planarly in an elongated dielectric to produce a 3-phase cable. The arrangement increases the magnetic field parallel to the tapes thereby reducing ac losses.

Abstract: A process to produce magnesium diboride objects from boron objects with a similar form is presented. Boron objects are reacted with magnesium vapor at a predetermined time and temperature to form magnesium diboride objects having a morphology similar to the boron object's original morphology.

Abstract: Superconducting cables, wires and methods of making the same are disclosed. The cables can offer improved flexibility while maintaining a high current carrying capacity. Advantageously, the superconducting filaments of the cables can be formed from relatively brittle materials having comparatively high critical temperatures and/or comparatively high critical magnetic fields. Magnet systems can be formed using these cables without using the conventional “react-then-wind” method.

Abstract: A high-performance Nb3Al extra-fine multifilamentary superconducting wire is produced simply and inexpensively through the improvement of critical values, Tc, Hc2 and Jc, without the addition of third elements such as Ge, Si and Cu. A first rapid heating and quenching treatment is applied to an Nb/Al composite wire having an atomic ratio of Al to Nb from 1:2.5 to 1:3.5 and having an extra-fine multifilamentary structure to form a BCC alloy phase comprising Nb with Al supersaturatedly dissolved therein wherein the treatment comprises heating the composite wire up to a temperature not lower than 1900° C. within two seconds and then introducing it into a molten metal at a temperature not higher than 400° C. to rapidly quench it.

Abstract: An apparatus and process for applying a superconductive layer on an elongate substrate that includes moving the elongate substrate through a heating zone, applying a pulsed laser beam against a target, having a length, that is coated with superconductive material wherein particles of superconductive material are separated from the target and strike the elongate substrate with a plasma beam in the heating zone, and oscillating the pulsed laser beam across the target to provide a substantially uniform coating of superconductive material on the elongate substrate.

Abstract: There is disclosed a continuous process for the formation of a superconducting wire utilizing magnesium diboride powder. The process provides a long length, low cost strand of superconducting wire which can be used in a monofilament or multifilament form.

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 or a high temperature liquid metal 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 multifilamentary oxide superconducting wire having a low aspect ratio and a relatively high critical current density, and being suitable for a stranded wire. In order to produce such a wire, a tape-shaped, multifilamentary oxide superconducting wire prepared by the powder-in-tube process is cut along its length. The resulting multifilamentary oxide superconducting wires have a width smaller than that of the tape-shaped wire. The resulting wires typically have an aspect ratio of one to two. The filaments of the resulting wires are in the shape of a ribbon extending in the longitudinal direction, and arranged substantially parallel to each other and in layers. The filaments have an aspect ratio greater than two. The filaments inside include a filament having a portion substantially not covered with the stabilizer.

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.