Abstract: Disclosed is a splicing method of two second-generation ReBCO high temperature superconductor coated conductors (2G ReBCO HTS CCs), in which, with stabilizing layers removed from the two strands of 2G ReBCO HTS CCs through chemical wet etching or plasma dry etching, surfaces of the two high temperature superconducting layers are brought into direct contact with each other and heated in a splicing furnace in a vacuum for micro-melting portions of the surfaces of the high temperature superconducting layers to permit inter-diffusion of ReBCO atoms such that the surfaces of the two superconducting layers can be spliced to each other and oxygenation annealing for recovery of superconductivity which was lost during splicing.

Abstract: A device and method for making a persistent joint allowing end terminations of superconducting MgB2 wire to be joined with a superconducting bridge. Superconducting electromagnetic coils may be joined in series or joining of coil assemblies to current sources and the two ends of a persistent switch. The device includes wire filaments with end preparation exposing reacted MgB2, inserted into a block and surrounded with Mg+B and/or MgB2 in powder, solid, slurry or sol-gel form and subsequently reacted to establish a bridge of superconducting MgB2 electrically connecting the superconducting MgB2 wires. Autonomous operation of the superconducting background magnet coils in magnetic resonance imaging (MRI) and nuclear magnetic resonance (NMR) devices are allowed, or similar devices where autonomous operation of an MgB2 based superconducting magnet is required. The low resistant joint will also be beneficial for other superconducting applications such as fault current limiters, motors, generators, etc.

Abstract: A process for fabricating an ultra-low-resistance superconducting joint that has high shielding characteristics. The process includes: corroding copper on the outer surface at the end of a NbTi/Cu superconducting wire to form terminal NbTi superconducting filaments; inserting same number of NbTi superconducting filaments into each through hole of the niobium layer of a Nb/NbTi/Cu multilayer composite rod; pressing at the outside of the Nb/NbTi/Cu multilayer composite rod to combine the Nb/NbTi/Cu multilayer composite rod and NbTi superconducting filaments together to form a joint; and inserting the joint into a YBCO tube, and then filling the YBCO tube with molten bismuth-lead-tin-cadmium (BiPbSnCd) alloy solder to form a superconducting joint with high shielding and low resistance characteristics.

Abstract: A junction box is provided which allows serial connection of the individual conductors of at least one high temperature superconductor (HTS) wire bundle. The junction box includes an electrical interface device disposed within a junction box housing. The interface device is configured receive both ends of each conductor of each HTS wire bundle, and to provide a superconductive electrical connection between respective first ends of conductors to respective second ends of other wire bundle conductors to form at least one superconductive multi-turn electromagnetic winding.

Abstract: A method for superconductingly connecting two or more wires (1, 2), each comprising at least one filament (3a-3d) that contains MgB2 or a mixture of Mg and B, wherein a superconducting connection is realized through exposed end regions (4a) of the filaments (3a-3d) via an MgB2 matrix, is characterized in that a bulk boron powder (4) is provided into which the exposed end regions (4a) of the filaments (3a-3d) of the wires (1, 2) project, the boron of the bulk boron powder (4) being present in amorphous modification. The bulk powder (4) is then compacted together with the projecting exposed end regions (4a) of the filaments (3a, 3b) to form a compressed element (8) and the compressed element (8) is infiltrated with molten magnesium (10) from the surface (13) of the compressed element (8). The method improves the quality, in particular, the current-carrying capacity and the critical magnetic field strength of a superconducting connection of MgB2 superconducting wires.

Abstract: A method for connecting two or more superconducting wires (1, 2), each comprising at least one filament (3a-3b) that contains MgB2, wherein the superconducting connection is realized through exposed end regions (13) of the filaments (3a-3d) via a superconducting matrix, is characterized in that a bulk powder (4) of a high-temperature superconductor (HTS) powder with a transition temperature of Tc>40K is provided, into which the exposed end regions (13) of the filaments (3a-3d) project, wherein the Boron of the Boron powder of the bulk powder (4) is in amorphous modification, and the bulk powder (4) is compacted together with the projecting exposed end regions (13) of the filaments (3a-3d) to form a compressed element (8). The method improves the quality, in particular, the current carrying capacity and the critical magnetic field strength of a superconducting connection of two MgB2 wires.

Abstract: An electrical component comprises a superconductive wire, the wire comprising a first wire segment joined to a second wire segment, wherein the first wire segment and the second wire segment differ in at least one property selected from the group consisting of magnetic field tolerance, temperature tolerance, ac loss, and strain tolerance, and wherein the magnetic field tolerance is measured by the relationship of critical current Ic to magnetic field H at a given temperature T below critical temperature Tc, the temperature tolerance is measured by the relationship of critical current Ic to temperature T at a given magnetic field below critical magnetic field Hc, the ac loss is measured by the amount of ac loss versus the frequency and magnitude of applied ac currents and fields, and the strain tolerance is measured by critical current Ic degradation with strain.

Abstract: A two-sided joint for splicing two laminated wires together, while preserving the mechanical integrity of the wire is disclosed. The two-sided joint can splice two laminated HTS wires having tapered ends and includes a bottom strap and a top strap. Under one aspect, a laminated, spliced superconductor wire includes a superconductor joint, which includes first and second superconductor wires, each wire including a laminate layer, a substrate layer overlaying the laminate layer, a buffer layer overlaying the substrate layer, a superconductor layer overlaying the buffer layer, a gap layer overlaying the superconductor layer, and a laminate layer overlaying the gap layer, a first HTS strap in electrical connection with the second laminate layer of the first laminate wire and the second laminate layer of the second laminate wire, and a backing strap proximate to the first laminate layer.

Abstract: A multiphase superconducting cable connection structure includes a connection box accommodating three conductor connects connecting a superconductor of a cable core of each phase extracted from a pair of 3-phase superconducting cables, a solid insulation member fixed to an outer circumference of each conductor connect, and a metal flange fixing the solid insulation member to the connection box. By fixing the metal flange to the connection box (a refrigerant vessel), the conductor connect can be positioned and the conductor connector's movement caused as the cable core thermally contracts can be reduced. The structure can help to position the conductor connect in the connection box and reliably hold it at a prescribed position.

Abstract: The present invention provides a method for joining an RE123 oxide superconductor matrix obtained by a melt process by the use of a solder material. The (110) plane of an RE123 oxide superconductor matrix obtained by a melt process is used as the plane to be joined, a solder material composed of an RE123 oxide superconductor having a lower melting point than the above-mentioned RE123 oxide superconductor is interposed between the planes to be joined, and this solder material is melted and then solidified to form a joining layer, thereby joining the matrices. The solder material can be a sinter, a melt-processed material, a powder, a slurry, or a molded powder.

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: A magnetic shield for a superconducting joint in a superconducting magnet coil includes a superconducting tubular shield of superconducting materials surrounding the joint. The shield extends on either side of the joint a distance equal to the inside diameter of the shield. The coil is wound with niobium titanium conductors. The superconducting shield produces a field anomaly that influences the homogeneity of the imaging volume and an acceptable disturbance in the imaging volume while at the same time providing an ambient field condition that allows the superconducting joint to have a sufficiently low resistance to minimize superconducting current capacity degradation.

Abstract: A bulk superconductor including a plurality of units each composed of a substrate and a superconductive layer of R--Ba--Cu--O, where R is selected from La, Nd, Sm, Eu, Gd, Y, Dy, Ho, Er, Tm, Yb and mixtures thereof, formed on the substrate. The units are arranged in a row or in a matrix such that the superconductive layers of respective units are superconductively joined with each other.

Abstract: A superconductive article is made from interconnected superconductive, metallic tapes. The tapes are mechanically joined, and electrically interconnected by a plurality of superconductive interconnections that extend between the tapes. Articles of the invention may be formed from tapes comprising superconductive Nb.sub.3 Sn having Nb.sub.3 Sn interconnections.

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 superconductive article is made from interconnected superconductive, metallic tapes. The tapes preferably are mechanically joined and electrically interconnected by a plurality of superconductive interconnections that extend between the tapes. The interconnections are formed by overlapping the edges of two tapes and forming a plurality of superconductive welds between the tapes in the overlapping regions. Articles of this invention may be formed from superconductive tapes made from Nb.sub.3 Sn having superconductive interconnections that also include Nb.sub.3 Sn.

Abstract: A method of forming a superconducting joint between the Nb.sub.3 Sn layer of a superconducting tape and a superconducting NbTi wire through use of a Pb-Bi bath, joint securing arrangement and mold around the joint.

Abstract: A superconductive article is made from interwoven superconductive, metallic tapes. The interwoven tapes are electrically interconnected by a plurality of superconductive interconnections that extend between the interwoven tapes. Articles of the invention may be formed from tapes comprising superconductive Nb.sub.3 Sn having Nb.sub.3 Sn interconnections.

Abstract: A superconductive device for helping shield magnetic field comprises at least two members; a layer containing superconductive oxide over each of said members; means for connecting said members to form a substrate; and means for connecting said layers containing superconductive oxide along a joint in which said members are connected.

Abstract: A conductor splice and splice support structure and method of assembly for use with cable-in-conduit superconductor cable of the type having a plurality of spaced sub-cables each including stabilizer and superconductor strands in an annular tube. Two transition ramp members, each having a cross section varying from a first end conforming to the cable configuration to a second end having an enlarged, oval, configuration have a plurality of surface grooves each sized to hold one sub-cable. Between the two transition ramp members is provided a main support member having grooves aligned with the transition members grooves. The main support member grooves are sized to hold two overlapping sub-cables. Preferably, a braid of superconductor material is placed around the overlapping sub-cable ends. The space within the grooves surrounding the sub-cables is preferably filled with solder.

Abstract: A low resistance splice for electrically connecting the ends of two superconducting cables and a method for making the splice. Two cables formed from superconducting material are positioned in close proximity, either overlapping or axially aligned and extending in opposite directions away from the splice. At least one strand of superconducting material is wrapped over both cables in a pressure relationship assuring good electrical contact between cable ends and strands. Solder is melted and applied to hold the strands against the cables. Where the cables overlap, solder may be used at the overlap interface to add mechanical strength. The strands may be in the form of a helical winding around overlapping cable ends or in the from of a braided tube surrounding and pressed against either overlapping or axially aligned cables. In the axial embodiment, the cables with the strand wrap may be pressed into a slot and the slot filled with solder to hold the cables and strands in position.

Abstract: A superconducting magnet shield includes a plurality of overlapping NbTi sheets welded together with a plurality of welds extending along elongated parallel slots in the overlap region with the slots extending in the direction of superconducting current flow.

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 superconducting joint includes a niobium-tin superconducting composite member, a niobium-tin superconducting wire diffusion bonded to the superconducting composite, a spacer diffusion bonded to the superconducting wire, a support diffusion bonded to the spacer and a superconducting member in electrical contact with the superconducting composite. According to the method of the invention, a wire comprising unreacted niobium and tin is machined to form a tapered end having a first tapered surface exposing the wire interior and an opposing surface. A complementary spacer having the taper substantially similar to that of the wire is assembled with the wire so that the tapered wire and the tapered spacer in surface contact with one another such that the spacer occupies the area of the wire removed by machining and the exposed tapered surface remains still exposed.

Abstract: Disclosed herein is a method which enables permanent current junction of a tape-type oxide superconducting wire and suppresses reduction of its critical current. An end portion of a tape-type wire (10) to be joined is removed to expose oxide superconductor filaments. Another tape-type wire (10') to be joined with the wire (10) is processed in a similar manner. The tape-type wires (10, 10') are so superposed that the surfaces exposing the filaments face with each other, and the superposed portions are pressed in a direction perpendicular to principal surfaces of the tapes and heat treated at a temperature of 800.degree. to 900.degree. C., to be completely joined with each other.

Abstract: An electrical connection between an electric conductor and an oxide superconductor is effected without the intermediary of a thin insulating layer that is formed by leaving the oxide superconductor in the atmosphere. This electrical connection is formed by removing the thin insulating layer that is formed by leaving the oxide superconductor in the atmosphere, and by electrically connecting the electric conductor and an exposed surface of the oxide superconductor.

Abstract: An oxide superconductor lamination member has a base, precious metal plates and an oxide superconductor layer. The precious metal plates and the oxide superconductor layer are successively laminated on the base, and the precious metal plates overlap each other at their ends. Another oxide superconductor lamination member has precious metal bases, and an oxide superconductor layer lamination on the precious metal bases. The precious metal bases overlap each other at their ends. End portions of the precious metal plates (bases) are connected by an adhesive so as to form a lap joint. The lap joint of the precious metal plates (bases) are covered with a precious metal foil.

Abstract: A superconducting joint includes a niobium-tin superconducting composite member, a niobium-tin superconducting wire diffusion bonded to the superconducting composite, a spacer diffusion bonded to the superconducting wire, a support diffusion bonded to the spacer and a superconducting member in electrical contact with the superconducting composite. According to the method of the invention, a wire comprising unreacted niobium and tin is machined to form a tapered end having a first tapered surface exposing the wire interior and an opposing surface. A complementary spacer having the taper substantially similar to that of the wire is assembled with the wire so that the tapered wire and the tapered spacer in surface contact with one another such that the spacer occupies the area of the wire removed by machining and the exposed tapered surface remains still exposed.

Abstract: This invention relates to a superconducting joint which is more commonly referred to as, a pigtail joint, for use in superconducting magnets. Such structures of this type, generally, exhibit total superconducting behavior at temperatures below the transition value of the superconducting joint and have high electrical resistance at temperatures above the transition point of the superconducting joint.

Abstract: An apparatus for forming a superconductive joint in tape or wire has features which include a closeable vessel with gas inlets for depositing a superconducting layer by chemical vapor deposition, and a form in combination with current clamps and conductive leads to heat a length of tape to a temperature effective to deposit a superconductive coating thereon. Preferably, the form and associated structure are unitary with a base plate which seals the vessel.

Abstract: A method and apparatus for automating superconducting tape splices is disclosed. In particular, a TIG welding torch is automatically traversed in front of two superconducting foils which are held in an overlapping relationship so that a weldment is created between the two foils and a splice is eventually created. The torch is automatically traversed by use of a stepper motor and a motor control which controls the direction of traverse and the traverse speed.

Abstract: Two Nb.sub.3 Sn superconducting tapes are overlapped by an amount equal to about two times the width of the superconducting tapes. A filler material of material substantially similar to the tapes is placed between the two tapes in the overlapped region. A NdYAG laser (4) sends a 20-40 watt beam focused by a lens that heats the tapes to create a bridge of superconductivity material formed over the region where the tapes are joined.

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: Superconducting joints between superconducting tape ends are produced by a series of operations which includes stripping non-superconductive material from the tape ends, joining them with a conductive coating and depositing a superconductive alloy layer thereon, typically of triniobium tin, by a chemical vapor deposition reaction of hydrogen with the corresponding metal halides. Certain of the steps are performed in an inert atmosphere free from moisture, elemental hydrogen and elemental oxygen, typically a helium atmosphere.

Abstract: Superconducting tapes having an inner laminate comprised of a parent-metal layer, a superconductive alloy layer on the parent-metal, a reactive-metal layer, and an outer laminate soldered thereon are joined in a superconducting joint by the method of this invention. The outer laminate is removed to form exposed sections, and the tapes are positioned so that the exposed sections are in contact. A melt zone within the exposed sections where the exposed sections are in contact is melted. The melt zone is at least large enough to provide sufficient parent-metal, superconductive alloy, and reactive-metal to form a melt that resolidifies as a continuous precipitate of the superconductive alloy. The melt resolidifies as a continuous precipitate of the superconductive alloy that is continuous with the superconductive alloy on the superconducting tape.

Abstract: Superconducting tapes having an inner laminate comprised of a parent-metal layer, a superconductive alloy layer on the parent-metal, a reactive-metal layer, and an outer laminate soldered thereon are joined in a superconducting joint by the method of this invention. The outer laminate, reactive-metal layer, and superconductive alloy layer are removed to form exposed sections of the parent metal layer. The tapes are positioned so that the exposed sections are in contact. Metallurgical bonding, for example by spot welding, forms bridges between the parent-metal layers. The joined exposed sections are heated in a protective atmosphere, and in the presence of excess reactive metal to form a continuous layer of the superconductive alloy on the bridge and the exposed areas that is continuous with the superconductive alloy layer on the superconducting tape.

Abstract: A superconducting electrical conductor comprises a porous substrate of bonded fibers which are coated by ceramic oxide superconducting material of the perovskite type so that its critical temperature of superconductivity is at or above the boiling point of liquid nitrogen. To form electrical cable, the conductor is encased within an inner tube. An outer tube surrounds the inner tube and defines an evacuated annular space therewith. This provides a thermal barrier between substrate, which will be bathed by liquid nitrogen, and the ambient. Electrical and heat insulation surrounds the outer tube.Joint connectors in the form of multiple rigid rods, each coated by superconducting material and held in a perforated frame, are used to connect facing ends of the substrate to form an electrical connection from one length of conductor to the next.