1102 results about "Superconducting wire" patented technology

Multiple SQUID magnetometers that include at least two SQUID loops, each of which is composed of at least two Josephson Junctions connected in parallel with superconducting wires, are provided. The SQUID loops are fabricated such that they share a common Josephson Junction. Devices and application that employ the multiple SQUID magnetometers are also provided.

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.

In order to provide a flexible oxide superconducting cable which is reduced in AC loss, tape-shaped superconducting wires covered with a stabilizing metal are wound on a flexible former. The superconducting wires are preferably laid on the former at a bending strain of not more than 0.2%. In laying on the former, a number of tape-shaped superconducting wires are laid on a core member in a side-by-side manner, to form a first layer. A prescribed number of tape-shaped superconducting wires are laid on top of the first layer in a side-by-side manner, to form a second layer. The former may be made of a metal, plastic, reinforced plastic, polymer, or a composite and provides flexibility to the superconducting wires and the cable formed therewith. Methods of forming and terminating a triaxial superconductor are disclosed.

A superconductor structure is manufactured by forming a channel within a substrate along a surface of the substrate, depositing a material within the channel of the substrate, where the material includes one of a superconductor material and a precursor for a superconductor material, and thermally treating the substance within the channel of the substrate so as to form an elongated superconductor wire formed as a single, cohesive structure. The substrate can further include a plurality of channels with superconductor wires formed within the channels. In addition, a cable is formed including a bundle of individual superconductor wires arranged at different spatial positions with respect to each other.

A superconducting wire includes first and second superconducting layers disposed on one or more substrates in stacked relationship, the first superconducting layer comprising a high temperature superconducting oxide of a first composition and the second superconducting layer comprising a high temperature superconducting layer of a second composition, wherein the first and second compositions are different. The first superconductor layer optionally includes a high temperature superconductor composition selected to provide enhanced critical current (Ic(c)) in the presence of magnetic fields perpendicular to surface of the superconducting layer (H//c). The second superconductor layer optionally includes a high temperature superconductor composition selected to provide enhanced critical current (Ic) in the presence of magnetic fields parallel to surface of the superconducting layer (H//ab).

The invention discloses a preparation method for an NbTi/Cu multi-core composite superconducting wire with a rectangular section, which comprises the following steps of: firstly, assembling an NbTi bar, a pure Nb inner pipe and an oxygen-free copper sheath in turn to form an NbTi/Cu composite sheath, sealing an upper end cap and a lower end cap of the NbTi/Cu composite sheath through vacuum welding, and then performing primary extrusion to obtain an NbTi/Cu composite bar; secondly, drawing and scaling the composite bar, and keeping on drawing the composite bar to obtain a hexagonal core rod, and performing assembling for the second time; and thirdly, performing vacuum solder sealing, hot isostatic pressing, secondary extrusion, bar drawing and scaling on the sheath which is assembled in the second time to finally obtain the NbTi/Cu multi-core composite superconducting wire with the rectangular section. The preparation method has the advantages of simple process flow, low preparation cost and good preparation effect, improves the fill factor among windings in the process of coiling a superconducting magnet but simultaneously keeps high critical current density for the wire, and overcomes the defects that the conventional four-high mill or forming roll mill is unevenly stressed, is difficult to process and the like in the rolling process.

The disclosed adaptor between cold junction of leading wire in heavy current of high-temperature superconductor and low resistance of superconducting transmission line includes structure: welding piles of high-temperature superconductor arranged in spaces to outer wall of support tube made from stainless steel in low thermal conductance; welding warm end in piles of high-temperature superconductor to transition piece of copper; through braze welding, cold end in piles is joined to NbTi/Cu superconducting line; cross winding NbTi/Cu line on inner copper tube sheathed inside outer copper tube; cooling superconducting line and copper connector by using liquid helium between inner and outer copper tubes. Features are: simple structure, suitable to connection under 20kA. In the invention, resistance of adaptor is lowered as 1.4-4.6n ohm. In supercritical quantity of helium flow 4g/s, all loss of 6 pieces of adaptor and 12 pieces of butt end of transmission line is less than 0.1Mpa.

An improvement is disclosed in the method for producing a multifilament (Nb, Ti)₃ Sn superconducting wire by the steps of preparing a plurality of Nb or Nb alloy rods where Nb or Nb alloy monofilaments are encased in copper or copper alloy sheaths; packing the Nb or Nb alloy rods within a copper containing matrix to form a packed subelement for the superconducting wire; providing sources of Sn, and sources of Ti within said subelement; assembling the subelements within a further copper containing matrix; and diffusing the Sn and Ti into the Nb or Nb alloy rods to form (Nb, Ti)₃ Sn. The method is improved by diffusing the Ti into the Nb from a minor number of Ti dopant source rods which are distributed among the Nb or Nb alloy rods.

The invention belongs to the technical field of superconduction and particularly relates to an uninsulated superconducting magnet. The uninsulated superconducting magnet comprises a coil framework and a superconducting wire wound on the coil framework, wherein the surface of the superconducting wire is free from an insulating layer or is wrapped with an incomplete insulating layer, a mixture of an electroconductive material, a heat-conducting material, a curing material and a wetting material is filled among the turns of the superconducting wire, the inter-turn resistance is 0.1ohm-100kilohm, and in terms of volume percentage of all materials, the uninsulated superconducting magnet comprises 0.01-99.9% of the electroconductive material, 0-99.9% of the heat conducting material, 0-99% of the curing material and 0-5% of the wetting material. According to the uninsulated superconducting magnet disclosed by the invention, electroconductive components are filled in each turn of the superconducting coil so that the inter-turn resistance is maintained higher, not only is the inter-turn uninsulated characteristic brought into play, but also the charging excitation and the quench protection of the superconducting magnet are facilitated.

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.

This patent application relates to the use of thin high temperature fibers, specifically optical fibers, for use as a substrate material in the fabrication of long-length low temperature superconducting and high temperature superconducting wire. The superconducting material is deposited on the fiber using either a thin or thick film deposition technique. The fiber can have a dual use in the transmission of data using either traditional optical means or the transmission of electrical current via the deposited superconductor. A buffer layer or layers is used between the high temperature fiber and the superconductor to promote grain alignment and enhance the current carrying capacity of the wire.

The invention relates to a single-core or multicore iron-based compound superconducting tape prepared from a silver sheath. The conductor core of the tape is an iron-based compound with superconducting property, and silver or silver alloy material is coated outside the conductor core. Other metals or alloy materials can also be coated outside a silver or silver alloy sheath. The superconducting tape is prepared by using a powder tubulated method comprising the following steps of: putting the initial powder of the iron-based compound into a silver tube, a silver alloy tube or a composited tube of silver and other metals; compactly filling the initial powder in the tube; after both ends of the tube are closed, swaging, drawing, rolling and processing the metal tube into wires and tapes; and then obtaining the superconducting tape by vacuum or inert atmosphere annealing. Due to the fact that a conversion zone does not exist between the superconducting core and the sheathed material after annealing and silver steam generated by the silver sheath at the temperature removes FeAs phase, the crystal grain connectivity of the iron-based superconductor is improved. The novel iron-based compound superconducting wire or tape has good current transportation property.

The invention discloses a low temperature superconducting assembly with low joint resistance for a high temperature superconducting current lead cold end. The resistance of a 40-70kA high temperature superconducting super current lead of which the lower end is connected with a low temperature superconducting bus must be as low as 1 nano-ohm. A rectangular section niobium-titanium/copper superconducting wire or a high conductivity copper material and a paired box type joint structure connected with the superconducting bus are adopted in the low temperature superconducting assembly. Tests prove that the joint resistance of the low temperature superconducting assembly and a high temperature superconducting assembly can be as low as 0.5 nano-ohm, and the joint resistance of the superconducting bus is lower than 1 nano-ohm. The low temperature superconducting assembly is a middle result for developing super current leads of an international thermonuclear fusion test reactor and has the characteristics of novel conception and low manufacturing cost.

An apparatus and method for manufacturing a superconducting low-pass filter for quantum computing devices. The apparatus includes a plurality of containers and input and output ports connected to opposite ends of the apparatus. A plurality of coils of superconducting wire are wound using a mandrel. An adhesive is applied to the coils for maintaining a wound state. Each of the coils are positioned in each of the containers and electrically connected to each other with at least one coil being connected to the input port and at least one coil being connected to the output port. The coils are released or expanded from their wound state using an adhesive solvent. The containers are then filled with a conductive polymer and the containers are closed with one or more covers.

A magnesium diboride superconducting wire has excellent conduction property and stability. The superconductive connection of the magnesium diboride superconducting wire covered with a superconducting coating layer and a same or different kind of another superconducting wire are connected in a metal tube filled with a solder by way of the superconductive coating layer.

Tape-shaped superconducting wires are made by forming a superconducting film on the substrate. At least the superconducting film is slit, electrically separated into a plurality of superconducting film parts each having a rectangular cross section and arranged in parallel to form parallel conductors. This provides superconducting wires capable of containing AC loss. A superconducting coil is made by winding the superconducting wires described above, wherein the provision of a coil structure containing at least partially a part wherein the perpendicular interlinkage magnetic flux acting among various conductor elements of the parallel conductors by the distribution of the magnetic field generated by the superconducting coils cancel mutually enables a simple structure without transposition to cancel mutually the interlinkage magnetic flux by the perpendicular magnetic field against wires, to contain circulating current within the wires by the perpendicular magnetic field and to make shunt current uniform. This provides a low-loss superconducting coil.

The invention belongs to the field of superconducting material and relates to a superconducting strand based on a ReBCO high-temperature superconducting tape. The superconducting strand comprises a superconducting strand core and a coating layer. The ReBCO high-temperature superconducting tape is cut into tapes which are arranged and stacked to be the superconducting strand core with circular, square or rectangular cross section; the coating layer is made of copper tapes, aluminum tapes, aluminum alloy tapes, stainless steel tapes or ReBCO coating superconducting tapes; the coating layer is rolled and coated on the superconducting strand core. A laser Ag welding technology is used for carrying out butt-seam welding on the coating tapes. The superconducting strand provided by the invention expands the application range of the coating superconductor, improves engineering current density, flexibility and mechanical strength of the superconducting wire, and is applicable to a superconducting cable, a current guide wire, and the like.

The invention discloses a preparation method for a multi-core MgB2 superconducting wire/band. The method comprises the following steps of: 1, preparing precursor powder; 2, feeding the precursor powder into a Nb/Cu composite metal tube to obtain a tubing complex; 3, performing rotary swaging and drawing treatment, and thus obtaining single-core wires; 4, placing a copper-niobium composite rod anda plurality of single-core wires into an anaerobic copper tube for secondary assembly to obtain a secondary composite rod, performing the rotary swaging and drawing treatment, and thus obtaining multi-core wires; and 5 sintering in vacuum, and thus obtaining the multi-core MgB2 superconducting wire; or rolling into multi-core bands, then sintering in vacuum, and thus obtaining the multi-core MgB2superconducting band. By the preparation method, powder is subjected to high-temperature heat treatment, so that the condition that high-activity carbon which is decomposed from SiC can better replace boron can be ensured, and the improvement on the critical current density of the wire/band in a magnetic field is better facilitated. Due to the adoption of a center copper-niobium composite bar enhanced conductor structure, the improvement on the density of the MgB2 superconducting wire is facilitated, the connectivity of MgB2 crystal grains is enhanced, and the critical current density of the wire/band is improved.

In a superconducting coil, a parallel conductor includes a plurality of superconducting wires bundled and wound in a coil. The superconducting wires have at least two connections therebetween. A current source connected to the superconducting wires to form a loop via the superconducting wires and the connection to supply a current in the loop when a quench is detected. A superconducting magnet includes the superconducting coil, a persistent current switch connected to the superconducting coil, and a quench detector configured to detect quench occurring in the superconducting coil.

The present invention discloses a specialized device for measuring the resistance of a superconducting line joint, comprising a low temperature Dewar unit, a room temperature tube unit, a background magnet unit, an excitation magnet unit, a linkage frame unit, a weakening magnetic field measuring unit, etc. The specialized device has the advantages that only the room temperature tube is required to be moved out from the low temperature Dewar via a guide rail when a sample loop of the measured superconducting line joint is replaced, so that the volatilization amount of the liquid helium in an experimental process is reduced. The background magnet is positioned on the lateral side of a Hall element which measures the weakening magnetic field of the sample loop of the superconducting line joint. Compared with being positioned at the lower side of the Hall element, the background magnet positioned at the lateral side of the Hall element reduces the influence of the background magnet to the fact that the Hall element measures the weakening magnetic field generated by the sample loop of the superconducting joint. With the room temperature tube technical, the Hall element is arranged inside the room temperature tube, namely a normal temperature Hall sensor measures the weakening magnetic field of the sample loop of the superconducting joint. The cost of the device is reduced and the reliability of the measurement is improved.

The invention provides a superconducting magnet which comprises a vacuum container and a refrigerator. A cold screen and a superconducting coil are arranged in the vacuum container; superconducting wires are wound on a coil framework to form the superconducting coil, and two free ends of the superconducting coil are connected with a superconducting switch by superconducting connectors to form a closed superconducting circuit; the refrigerator is arranged on the vacuum container and comprises a primary cold head and a secondary cold head, and the primary cold head is thermally connected with the cold screen; the superconducting wires are made of superconducting materials with critical superconducting transit temperatures higher than 35 K; the superconducting connectors are made of superconducting welding flux with a low melting point, can be cooled by the aid of the secondary cold head or cooling media and accordingly can be assuredly in superconducting states. Compared with low-temperature closed-loop superconducting magnets in the prior art, the superconducting magnet has the advantage of high superconducting stability.