WO2018211701A1 - Superconducting wire, superconducting wire joining method, superconducting coil, and superconducting device - Google Patents

Superconducting wire, superconducting wire joining method, superconducting coil, and superconducting device Download PDF

Info

Publication number
WO2018211701A1
WO2018211701A1 PCT/JP2017/018880 JP2017018880W WO2018211701A1 WO 2018211701 A1 WO2018211701 A1 WO 2018211701A1 JP 2017018880 W JP2017018880 W JP 2017018880W WO 2018211701 A1 WO2018211701 A1 WO 2018211701A1
Authority
WO
WIPO (PCT)
Prior art keywords
superconducting
layer
wire
superconducting layer
joining
Prior art date
Application number
PCT/JP2017/018880
Other languages
French (fr)
Japanese (ja)
Inventor
康太郎 大木
永石　竜起
Original Assignee
住友電気工業株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 住友電気工業株式会社 filed Critical 住友電気工業株式会社
Priority to PCT/JP2017/018880 priority Critical patent/WO2018211701A1/en
Publication of WO2018211701A1 publication Critical patent/WO2018211701A1/en

Links

Images

Classifications

    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N—ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10N60/00—Superconducting devices
    • H10N60/80—Constructional details
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B12/00—Superconductive or hyperconductive conductors, cables, or transmission lines
    • H01B12/02—Superconductive or hyperconductive conductors, cables, or transmission lines characterised by their form
    • H01B12/06—Films or wires on bases or cores
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F6/00—Superconducting magnets; Superconducting coils
    • H01F6/06—Coils, e.g. winding, insulating, terminating or casing arrangements therefor

Definitions

  • the present disclosure relates to a superconducting wire, a superconducting wire joining method, a superconducting coil, and a superconducting device.
  • the superconducting wire described in Patent Document 1 has a first wire, a second wire, and a bonding layer.
  • the first wire includes a first superconducting layer formed of a high temperature superconductor.
  • the 2nd wire contains the 2nd superconducting layer constituted by the high temperature superconductor.
  • the bonding layer is composed of a high-temperature superconductor.
  • the first wire and the second wire are arranged so that the first superconducting layer and the second superconducting layer are opposed to each other through the bonding layer.
  • the crystal orientation of the bonding layer is along the crystal orientation of the first superconducting layer and the second superconducting layer.
  • the superconducting wire includes a first wire and a second wire.
  • the first wire has a first superconducting layer.
  • the second wire has a second superconducting layer and a bonding layer disposed on the second superconducting layer, and is disposed so that the bonding layer faces the first superconducting layer.
  • the material constituting the first superconducting layer, the second superconducting layer, and the bonding layer is a high-temperature superconductor.
  • the first superconducting layer includes a portion that is superconductingly bonded to the bonding layer.
  • the first wire and the second wire overlap each other while being spaced apart from each other around the bonding layer to be superconductively bonded to the first superconducting layer.
  • a superconducting wire connection method includes a step of preparing a first wire having a first superconducting layer and a second wire having a second superconducting layer, and a bonding layer on the second superconducting layer.
  • a step of forming, a step of applying pressure while heating between the first wire and the second wire with the first superconducting layer and the bonding layer facing each other, and a step of introducing oxygen into the bonding layer Prepare. The pressure is applied so that the first wire and the second wire are separated from each other around the bonding layer bonded to the first superconducting layer, including the portion where the first superconducting layer is bonded to the bonding layer.
  • a superconducting coil according to an aspect of the present disclosure includes the superconducting wire described above.
  • the superconducting wire is wound around the central axis of the superconducting coil.
  • a superconducting device includes the superconducting coil, a cryostat that stores the superconducting coil therein, and a refrigerator that cools the superconducting coil.
  • FIG. 1 is a top view of the superconducting wire according to the first embodiment.
  • FIG. 2 is a cross-sectional view taken along the line II-II in FIG. 3 is a cross-sectional view taken along line III-III in FIG. 4 is a cross-sectional view taken along line IV-IV in FIG.
  • FIG. 5 is a process diagram showing the superconducting wire joining method according to the first embodiment.
  • FIG. 6 is a cross-sectional view of the bonding portion in the heating and pressing step S3.
  • FIG. 7 is a cross-sectional view of a superconducting wire joint according to the second embodiment.
  • FIG. 8 is a top view of the superconducting wire according to the third embodiment.
  • FIG. 9 is a cross-sectional view taken along the line IX-IX in FIG. 10 is a cross-sectional view taken along the line XX of FIG.
  • FIG. 11 is a cross-sectional view taken along the line XI-XI in FIG.
  • FIG. 12 is a schematic diagram showing a state of a magnetic field when a coil is formed using a superconducting wire.
  • FIG. 13 is an enlarged schematic view in a region XIII in FIG.
  • FIG. 14 is a schematic cross-sectional view of a superconducting device according to the fourth embodiment.
  • the present disclosure has been made in view of such problems of the prior art. Specifically, the present disclosure provides a superconducting wire and a superconducting wire joining method that can reduce the time required to introduce oxygen into the joining layer.
  • the time required for the treatment for introducing oxygen into the bonding layer can be shortened.
  • the time required for the treatment for introducing oxygen into the bonding layer can be shortened.
  • the time required for the treatment for introducing oxygen into the bonding layer can be shortened.
  • the time required for the treatment for introducing oxygen into the bonding layer can be shortened.
  • a superconducting wire includes a first wire having a first superconducting layer, a second superconducting layer, and a bonding layer disposed on the second superconducting layer, and the bonding layer is A second wire disposed to face the first superconducting layer.
  • the material constituting the first superconducting layer, the second superconducting layer, and the bonding layer is a high-temperature superconductor.
  • the first superconducting layer includes a portion that is superconductingly bonded to the bonding layer.
  • the first wire and the second wire overlap each other while being spaced apart from each other around the bonding layer to be superconductively bonded to the first superconducting layer.
  • the first wire and the second wire are separated around the bonding layer to be superconductingly bonded to the first superconducting layer.
  • Oxygen passes between the first wire and the second wire and is supplied to the bonding layer that is superconductively bonded to the first superconducting layer. Therefore, according to the superconducting wire (1), the time for introducing oxygen into the bonding layer can be shortened.
  • the first superconducting layer may be superconductingly bonded to the bonding layer along the longitudinal direction of the first wire. According to the superconducting wire (2) above, the time for introducing oxygen into the bonding layer can be shortened.
  • the surface of the first superconducting layer on the bonding layer side may protrude from the periphery at the portion where the superconducting bonding with the bonding layer is performed. According to the superconducting wire (3) above, the time for introducing oxygen into the bonding layer can be shortened.
  • the first superconducting layer is constituted by a plurality of portions extending along the longitudinal direction of the first wire and separated from each other along the width direction of the first wire. May be.
  • the second superconducting layer may be constituted by a plurality of portions extending along the longitudinal direction of the second wire and separated from each other along the width direction of the second wire.
  • each of the first superconducting layer and the second superconducting layer is electrically separated. Therefore, when a coil is formed using the superconducting wire of (4), it is possible to reduce the shielding current due to the magnetic field generated by the current flowing through the coil.
  • the high-temperature superconductor may be REBCO.
  • the crystal orientation of the bonding layer may be along the crystal orientation of the first superconducting layer and the second superconducting layer. According to the superconducting wire (5), the time for introducing oxygen into the bonding layer can be shortened.
  • a superconducting wire joining method includes a step of preparing a first wire having a first superconducting layer and a second wire having a second superconducting layer, and joining on the second superconducting layer A step of forming a layer, a step of applying pressure while heating between the first wire and the second wire with the first superconducting layer and the bonding layer facing each other, and a step of introducing oxygen into the bonding layer With. The pressure is applied so that the first wire and the second wire are separated from each other around the bonding layer bonded to the first superconducting layer, including the portion where the first superconducting layer is bonded to the bonding layer.
  • the time for introducing oxygen into the bonding layer can be shortened.
  • the pressure is such that the first wire and the second wire are sandwiched by a pressure jig, and at least one of the pressure jig, the first wire, and the second wire. It may be applied by inserting a plate-like member between them. The plate-like member may be disposed at a position overlapping the first superconducting layer joined to the joining layer in plan view. According to the superconducting wire bonding method of (7) above, the time for introducing oxygen into the bonding layer can be shortened.
  • a superconducting coil according to an aspect of the present disclosure includes the superconducting wires of (1) to (5) above.
  • the superconducting wire is wound around the central axis of the superconducting coil.
  • a superconducting device includes the superconducting coil according to (8), a cryostat, and a refrigerator.
  • the cryostat houses a superconducting coil inside.
  • the refrigerator cools the superconducting coil.
  • FIG. 1 is a top view of the superconducting wire according to the first embodiment.
  • FIG. 2 is a cross-sectional view taken along the line II-II in FIG. 3 is a cross-sectional view taken along line III-III in FIG. 4 is a cross-sectional view taken along line IV-IV in FIG.
  • the superconducting wire according to the first embodiment has a first wire 1 and a second wire 2.
  • the first wire 1 and the second wire 2 are joined together.
  • the longitudinal direction of the first wire 1 is preferably along the longitudinal direction of the second wire 2.
  • the direction orthogonal to the longitudinal direction of the first wire 1 (longitudinal direction of the second wire 2) may be referred to as the width direction of the first wire 1 (width direction of the second wire 2).
  • the first wire 1 has a first superconducting layer 13. More specifically, the first wire 1 has a first base material 11, a first intermediate layer 12, a first superconducting layer 13, a first protective layer 14, and a first stabilization layer 15. ing.
  • the first base material 11 is made of, for example, a clad material in which stainless steel, a nickel (Ni) layer, and a copper (Cu) layer are stacked.
  • the first substrate 11 may be made of Hastelloy (registered trademark) or the like.
  • the first intermediate layer 12 is disposed on the first base material 11.
  • the first intermediate layer 12 is a layer for reducing lattice mismatch between the first base material 11 and the first superconducting layer 13.
  • the material used for the first intermediate layer 12 is appropriately selected according to the first superconducting layer 13.
  • the first intermediate layer 12 is, for example, cerium oxide (CeO 2 ).
  • the first intermediate layer 12 preferably has a uniform crystal orientation.
  • the first superconducting layer 13 is disposed on the first intermediate layer 12. It is composed of a high-temperature superconductor.
  • a high-temperature superconductor refers to a material having a superconducting transition temperature of liquid nitrogen temperature (77 Kelvin) or higher.
  • the high temperature superconductor constituting the first superconducting layer 13 is, for example, REBCO.
  • REBCO is (RE) Ba 2 Cu 3 O x
  • RE is, for example, yttrium (Y), gadolinium (Gd), europium (Eu), dysprosium (Dy), erbium (Er), lanthanum (La), thulium (Tm), rare earth elements such as ytterbium (Yb)).
  • the material which comprises the 1st superconducting layer 13 is not restricted to this.
  • the material constituting the first superconducting layer 13 may be, for example, Bi 2 Sr 2 Ca 2 Cu 3 O x (Bi-2223).
  • the first superconducting layer 13 preferably has a uniform crystal orientation. Specifically, the c-axis of the material constituting the first superconducting layer 13 is along the direction from the first intermediate layer 12 toward the first protective layer 14 (the thickness direction of the first superconducting layer 13). preferable. From another viewpoint, it is preferable that the ab surface of the material constituting the first superconducting layer 13 is parallel to the longitudinal direction and the width direction of the first wire 1.
  • the first protective layer 14 and the first stabilization layer 15 are layers for bypassing current when a quench occurs in the first superconducting layer 13 (a phenomenon in which a transition from a superconducting state to a normal conducting state) occurs.
  • the first protective layer 14 is disposed on the first superconducting layer 13.
  • the first stabilization layer 15 is disposed on the first protective layer 14.
  • the first protective layer 14 is made of, for example, silver (Ag).
  • the first stabilization layer 15 is made of, for example, Cu.
  • the second wire 2 has a second superconducting layer 23. More specifically, the second wire 2 has a second base material 21, a second intermediate layer 22, a second superconducting layer 23, a second protective layer 24, and a second stabilization layer 25. ing.
  • the 2nd base material 21 is comprised by the clad material which laminated
  • the second base material 21 may be made of Hastelloy (registered trademark) or the like.
  • the second intermediate layer 22 is disposed on the second base material 21.
  • the second intermediate layer 22 is a layer for reducing lattice mismatch between the second base material 21 and the second superconducting layer 23.
  • the material used for the second intermediate layer 22 is appropriately selected according to the second superconducting layer 23.
  • second superconducting layer 23 is REBCO
  • second intermediate layer 22 is, for example, CeO 2.
  • the second intermediate layer 22 preferably has a uniform crystal orientation.
  • the second superconducting layer 23 is disposed on the second intermediate layer 22. It is composed of a high-temperature superconductor.
  • the high temperature superconductor constituting the second superconducting layer 23 is, for example, REBCO.
  • the material which comprises the 2nd superconducting layer 23 is not restricted to this.
  • the material constituting the second superconducting layer 23 may be, for example, Bi-2223.
  • the high temperature superconductor constituting the second superconducting layer 23 is preferably the same as the high temperature superconductor constituting the first superconducting layer 13.
  • the second superconducting layer 23 preferably has a uniform crystal orientation. Specifically, the c-axis of the material constituting the second superconducting layer 23 is along the direction from the second intermediate layer 22 toward the second protective layer 24 (the thickness direction of the second superconducting layer 23). preferable. From another viewpoint, it is preferable that the ab surface of the material constituting the second superconducting layer 23 is parallel to the longitudinal direction and the width direction of the second wire 2.
  • the second protective layer 24 and the second stabilization layer 25 are layers for bypassing current when the second superconducting layer 23 is quenched.
  • the second protective layer 24 is disposed on the second superconducting layer 23.
  • the second stabilization layer 25 is disposed on the second protective layer 24.
  • the second protective layer 24 is made of, for example, Ag.
  • the second stabilization layer 25 is made of, for example, Cu.
  • the second wire 2 further has a bonding layer 3.
  • the first protective layer 14, the first stabilizing layer 15, the second protective layer 24, and the second stabilizing layer 25 are removed.
  • the bonding layer 3 is disposed on the second superconducting layer 23.
  • the first wire 1 and the second wire 2 are arranged so that the first superconducting layer 13 and the joining layer 3 face each other. .
  • the bonding layer 3 is composed of a high-temperature superconductor.
  • the high temperature superconductor constituting the bonding layer 3 is the same as the high temperature superconductor constituting the first superconductor layer 13 and the second superconductor layer 23.
  • the bonding layer 3 includes a first portion 3a, a second portion 3b, and a third portion 3c.
  • the second part 3b is separated from the first part 3a.
  • the first portion 3 a and the second portion 3 b are located at both ends in the width direction of the second wire 2, for example.
  • the third portion 3c is sandwiched between the first portion 3a and the second portion 3b.
  • the third portion 3c is superconductively joined to the first superconducting layer 13.
  • the first portion 3a and the second portion 3b are not joined to the first superconducting layer 13 (separated from the first superconducting layer 13).
  • the bonding layer 3 is overlapped with the first wire 1 and the second wire 2 being separated from each other around the bonding layer 3 that is superconductively bonded to the first superconductive layer 13. ing.
  • the bonding layer 3 is preferably superconductively bonded to the second superconducting layer 23 in the first portion 3a, the second portion 3b, and the third portion 3c.
  • the first superconducting layer 13 (second superconducting layer 23) and the joining layer 3 are superconductingly joined at a temperature not higher than the superconducting transition temperature of the first superconducting layer 13 (second superconducting layer 23). It means that current flows between the first superconducting layer 13 (second superconducting layer 23) and the bonding layer 3 in a superconducting state.
  • the first portion 3a, the second portion 3b, and the third portion 3c extend along the longitudinal direction of the first wire 1 and the second wire 2. That is, the bonding layer 3 is preferably superconductively bonded to the first superconducting layer 13 along the longitudinal direction of the first wire 1 and the second wire 2.
  • the first portion 3a has a width W1.
  • the second portion 3b has a width W2.
  • the third portion 3c has a width W3.
  • the width W ⁇ b> 1 is the width of the first portion 3 a in the width direction of the first wire 1 and the second wire 2.
  • the width W ⁇ b> 2 is the width of the second portion 3 b in the width direction of the first wire 1 and the second wire 2.
  • the width W ⁇ b> 3 is the width of the third portion 3 c in the width direction of the first wire 1 and the second wire 2.
  • a value obtained by dividing the width W3 by the sum of the width W1 and the width W2 is 0.13 or more and 0.75 or less.
  • the first superconducting layer 13 may have a first end at one end of the first wire 1 and a second end at the other end of the first wire 1.
  • the first wire 1 positioned at the other end may have a bonding layer 3 on the second end.
  • the bonding layer 3 may face the first end.
  • the first end portion may have a portion that is superconductively bonded to the bonding layer 3.
  • the one end and the other end of the first wire 1 may overlap with each other while being separated from each other.
  • FIG. 5 is a process diagram showing the superconducting wire joining method according to the first embodiment.
  • the superconducting wire bonding method according to the first embodiment includes a wire rod preparation step S1, a bonding layer forming step S2, a heating and pressing step S3, and a bonding layer oxygen introduction step S4. ing.
  • the first wire 1 and the second wire 2 are prepared.
  • the bonding layer forming step S2 the bonding layer 3 is formed.
  • the bonding layer 3 is formed on the second superconducting layer 23.
  • the bonding layer 3 In forming the bonding layer 3, first, an organic compound of an element constituting the high-temperature superconductor used in the bonding layer 3 is applied. Secondly, a heat treatment is performed on the coating film of the organic compound. Thereby, the coating film of the organic compound becomes a precursor of the high-temperature superconductor used for the bonding layer 3 (hereinafter, a film containing the precursor is referred to as a calcined film).
  • This precursor contains carbides of elements constituting the high-temperature superconductor used for the bonding layer 3.
  • This heat treatment is performed at a treatment temperature that is equal to or higher than the decomposition temperature of the organic compound and lower than the generation temperature of the high-temperature superconductor used in the bonding layer 3.
  • a heat treatment is performed on the calcined film.
  • the carbide contained in the calcined film is decomposed to become a high-temperature superconductor used for the bonding layer 3.
  • the heat treatment for the calcined film is performed in an atmosphere having an oxygen concentration of 1 percent or more.
  • the bonding layer 3 contains fine crystals of the high-temperature superconductor.
  • FIG. 6 is a cross-sectional view of the joint portion in the heating and pressing step S3.
  • the first wire 1 and the second wire 2 are arranged so that the bonding layer 3 and the first superconducting layer 13 face each other.
  • pressure is applied between the first wire 1 and the second wire (more specifically, between the first superconducting layer 13 and the second superconducting layer 23). In applying this pressure, heating is also performed.
  • This pressure includes a portion where the first superconducting layer 13 is joined to the joining layer 3, and the first wire 1 and the second wire 2 are separated from each other around the joining layer 3 joined to the first superconducting layer 13. To be applied.
  • the pressure is applied by holding the first wire 1 and the second wire 2 with the pressure jig 4 and at least one of the pressure jig 4, the first wire 1 and the second wire 2.
  • the pressure adjustment plate 5 is sandwiched between the two.
  • the pressure adjusting plate 5 is a plate-like member.
  • the pressure adjusting plate 5 is disposed at a position overlapping the first superconducting layer 13 bonded to the bonding layer 3 in plan view.
  • the pressure applied between the first superconducting layer 13 and the second superconducting layer 23 increases in a portion overlapping the pressure adjusting plate 5 in plan view.
  • fine crystals of the high-temperature superconductor contained in the bonding layer 3 are epitaxially grown along the crystal orientations of the first superconducting layer 13 and the second superconducting layer 23.
  • the pressure applied between the first superconducting layer 13 and the second superconducting layer 23 is relatively small in a portion that does not overlap the pressure adjusting plate 5 in plan view.
  • the fine crystals of the high-temperature superconductor contained in the bonding layer are epitaxially grown along the crystal orientation of the second superconducting layer 23, but not epitaxially grown along the crystal orientation of the first superconducting layer 13. That is, superconducting bonding between the bonding layer 3 and the first superconducting layer 13 is achieved in a portion overlapping the pressure adjusting plate 5 in a plan view, but in a portion not overlapping the pressure adjusting plate 5 in a plan view. 3 and the first superconducting layer 13 are not joined.
  • the bonding layer oxygen introduction step S4 oxygen is introduced into the bonding layer 3. Specifically, the first wire 1, the second wire 2, and the bonding layer 3 are subjected to heat treatment in an atmosphere containing oxygen, whereby oxygen is introduced into the bonding layer. Thus, the superconducting wire joining method according to the first embodiment is completed.
  • the first portion 3 a and the second portion 3 b are not joined to the first superconducting layer 13. Therefore, oxygen passes between the first part 3 a and the second part 3 b and the first superconducting layer 13 and is supplied to the third part 3 c joined to the first superconducting layer 13.
  • a path for supplying oxygen to the joining layer contributing to the superconducting junction is secured. The time for introducing oxygen into the layer 3 can be shortened.
  • FIG. 7 is a cross-sectional view at the junction of the superconducting wire according to the second embodiment.
  • the superconducting wire according to the second embodiment has a first wire 1 and a second wire 2.
  • the first wire 1 has a first superconducting layer 13.
  • the second wire 2 has a second superconducting layer 23 and a bonding layer 3.
  • the bonding layer 3 includes a first portion 3a, a second portion 3b, and a third portion 3c.
  • the first superconducting layer 13 is superconductingly joined to the third portion 3c.
  • the first wire 1 is separated from the first part 3a and the second part 3b.
  • the first superconducting layer 13 has a portion that is superconductively bonded to the bonding layer 3, and the first wire 1 and the second wire 2 around the bonding layer 3 that is superconductively bonded to the first superconductive layer 13. And overlap each other while being separated from each other.
  • the superconducting wire according to the second embodiment is common to the superconducting wire according to the first embodiment.
  • the first superconducting layer 13 has a first surface 13a and a second surface 13b.
  • the second surface 13b is the opposite surface of the first surface 13a.
  • the second surface 13b is a surface on the first intermediate layer 12 side.
  • the first surface 13a is a surface on the bonding layer 3 side.
  • the first surface 13a protrudes toward the second surface 13b at the portion facing the third portion 3c. That is, the first surface 13a protrudes from the periphery at a portion where the first conductive layer 13a and the bonding layer 3 are superconductively bonded.
  • the superconducting wire according to the second embodiment is different from the superconducting wire according to the first embodiment.
  • the superconducting wire according to the second embodiment a space is formed between the first portion 3a and the second portion 3b and the first surface 13a. Oxygen is supplied to the third portion 3c that is superconductingly bonded to the first superconducting layer 13 through this space. Therefore, according to the superconducting wire according to the second embodiment, the time for introducing oxygen into the bonding layer 3 that contributes to the superconducting junction can be shortened, similarly to the superconducting wire according to the first embodiment.
  • FIG. 8 is a top view of the superconducting wire according to the third embodiment.
  • the superconducting wire according to the third embodiment has a first wire 1 and a second wire 2.
  • FIG. 9 is a cross-sectional view taken along the line IX-IX in FIG. 10 is a cross-sectional view taken along the line XX of FIG.
  • FIG. 11 is a cross-sectional view taken along the line XI-XI in FIG.
  • the first wire 1 has a first superconducting layer 13.
  • the second wire 2 has a second superconducting layer 23.
  • the second wire 2 further has a bonding layer 3.
  • the first superconducting layer 13 is in superconducting junction with the third portion 3c.
  • the first wire 1 is overlapped while being separated from the second wire 2 at a portion facing the first portion 3a and the second portion 3b. That is, the first superconducting layer 13 has a portion that is superconductively bonded to the bonding layer 3, and the first wire 1 and the second wire 2 around the bonding layer 3 that is superconductively bonded to the first superconductive layer 13. And overlap each other while being separated from each other.
  • the superconducting wire according to the third embodiment is common to the superconducting wire according to the first embodiment.
  • the first superconducting layer 13 is constituted by a plurality of portions extending along the longitudinal direction of the first wire 1 and arranged at intervals along the width direction of the first wire 1.
  • the second superconducting layer 23 is composed of a plurality of portions that extend along the longitudinal direction of the second wire 2 and are arranged at intervals along the width direction of the second wire 2.
  • the superconducting wire according to the third embodiment is different from the superconducting wire according to the first embodiment.
  • Each of the plurality of portions of the first superconducting layer 13 opposes each of the plurality of portions of the second superconducting layer 23 via the bonding layer 3 (third portion 3c).
  • FIG. 12 is a schematic diagram showing the state of a magnetic field when a coil is formed using a superconducting wire. As shown in FIG. 12, a magnetic field MF is generated when a current flows through the coil 20. This magnetic field MF has a component MF1 in the coil radial direction and a component MF2 in the coil length direction.
  • FIG. 13 is an enlarged schematic diagram in region XIII of FIG.
  • the superconducting wire constituting the coil 20 has a superconducting layer 10.
  • Superconducting layer 10 is uniformly formed in the superconducting wire.
  • an eddy current shielding current
  • This shielding current further generates a magnetic field.
  • the central magnetic field of the coil 20 decreases, the central magnetic field of the coil 20 varies with time, and the magnetic field distribution of the coil 20 is organized.
  • the first superconducting layer 13 extends along the longitudinal direction of the first wire 1 and is arranged at intervals along the width direction of the first wire 1. It is composed of a plurality of parts.
  • the second superconducting layer 23 is composed of a plurality of portions that extend along the longitudinal direction of the second wire 2 and are arranged at intervals along the width direction of the second wire 2. Therefore, each part which comprises the 1st superconducting layer 13 and the 2nd superconducting layer 23 is electrically isolate
  • the first superconducting layer 13 is superconductingly joined to the third portion 3c. Further, in the superconducting wire according to the third embodiment, the first wire 1 is overlapped while being separated from the second wire 2 at a portion facing the first portion 3a and the second portion 3b. Therefore, oxygen is supplied to the bonding layer 3 bonded to the first superconducting layer 13 through the first wire 3 and the first wire 3 between the first portion 3 a and the second portion 3 b. Therefore, according to the superconducting wire according to the third embodiment, similarly to the superconducting wire according to the first embodiment, the time for introducing oxygen into the bonding layer 3 that contributes to the superconducting junction can be shortened.
  • FIG. 14 is a schematic cross-sectional view of a superconducting device according to the fourth embodiment.
  • the superconducting device according to the fourth embodiment includes a superconducting coil 110, a cryostat 120, and a refrigerator 130.
  • Superconducting coil 110 is disposed inside cryostat 120. More specifically, the heat shield 121 is disposed inside the cryostat 120, and the superconducting coil 110 is disposed inside the heat shield 121.
  • Superconducting coil 110 is formed by winding superconducting wire 111 around the central axis of superconducting coil 110.
  • the superconducting wire 111 is a superconducting wire according to the first to third embodiments.
  • the refrigerator 130 cools the superconducting coil 110 disposed inside the cryostat 120 to the superconducting transition temperature of the first superconducting layer 13 and the second superconducting layer 23 or lower.
  • the refrigerator 130 is, for example, a Gifford McMahon refrigerator.

Abstract

A superconducting wire according to an embodiment of the present invention is provided with a first wire material which has a first superconducting layer, and a second wire material which has a second superconducting layer and a joining layer disposed upon the second superconducting layer and which is disposed such that the joining layer faces the first superconducting layer. The material composing the first superconducting layer, the second superconducting layer, and the joining layer is a high-temperature superconductor. The first superconducting layer includes a portion which forms a superconducting junction with the joining layer. In the periphery of the joining layer that forms a superconducting junction with the first superconducting layer, the first wire material and the second wire material overlap while being separated from one another.

Description

超電導線、超電導線の接合方法、超電導コイル及び超電導機器Superconducting wire, superconducting wire joining method, superconducting coil and superconducting equipment
　本開示は、超電導線、超電導線の接合方法、超電導コイル及び超電導機器に関する。 The present disclosure relates to a superconducting wire, a superconducting wire joining method, a superconducting coil, and a superconducting device.
　従来から、国際公開第２０１６／１２９４６９号（特許文献１）に記載の超電導線が知られている。特許文献１に記載の超電導線は、第１線材と、第２線材と、接合層とを有している。第１線材は、高温超電導体により構成される第１超電導層を含んでいる。第２線材は、高温超電導体により構成される第２超電導層を含んでいる。接合層は、高温超電導体により構成される。第１線材及び第２線材は、第１超電導層と第２超電導層とが接合層を介して対向するように配置されている。接合層の結晶方位は、第１超電導層及び第２超電導層の結晶方位に沿っている。 Conventionally, a superconducting wire described in International Publication No. 2016/129469 (Patent Document 1) is known. The superconducting wire described in Patent Document 1 has a first wire, a second wire, and a bonding layer. The first wire includes a first superconducting layer formed of a high temperature superconductor. The 2nd wire contains the 2nd superconducting layer constituted by the high temperature superconductor. The bonding layer is composed of a high-temperature superconductor. The first wire and the second wire are arranged so that the first superconducting layer and the second superconducting layer are opposed to each other through the bonding layer. The crystal orientation of the bonding layer is along the crystal orientation of the first superconducting layer and the second superconducting layer.
国際公開第２０１６／１２９４６９号International Publication No. 2016/129469
　本開示の一態様に係る超電導線は、第１線材と、第２線材とを備える。第１線材は、第１超電導層を有する。第２線材は、第２超電導層と、第２超電導層上に配置される接合層とを有し、かつ接合層が第１超電導層と対向するように配置される。第１超電導層、第２超電導層及び接合層を構成する材料は、高温超電導体である。第１超電導層は、接合層と超電導接合される部分を含む。第１超電導層と超電導接合される接合層の周囲において、第１線材と第２線材とは、互いに離間しながら重なり合う。 The superconducting wire according to an aspect of the present disclosure includes a first wire and a second wire. The first wire has a first superconducting layer. The second wire has a second superconducting layer and a bonding layer disposed on the second superconducting layer, and is disposed so that the bonding layer faces the first superconducting layer. The material constituting the first superconducting layer, the second superconducting layer, and the bonding layer is a high-temperature superconductor. The first superconducting layer includes a portion that is superconductingly bonded to the bonding layer. The first wire and the second wire overlap each other while being spaced apart from each other around the bonding layer to be superconductively bonded to the first superconducting layer.
　本開示の一態様に係る超電導線の接続方法は、第１超電導層を有する第１線材と、第２超電導層を有する第２線材とを準備する工程と、第２超電導層上に接合層を形成する工程と、第１超電導層と接合層とが対向した状態で、第１線材と第２線材との間に加熱しながら圧力を印加する工程と、接合層に酸素を導入する工程とを備える。圧力は、第１超電導層が接合層と接合される部分を含み、かつ第１超電導層に接合される接合層の周囲において第１線材と第２線材とが互いに離間するように印加される。 A superconducting wire connection method according to an aspect of the present disclosure includes a step of preparing a first wire having a first superconducting layer and a second wire having a second superconducting layer, and a bonding layer on the second superconducting layer. A step of forming, a step of applying pressure while heating between the first wire and the second wire with the first superconducting layer and the bonding layer facing each other, and a step of introducing oxygen into the bonding layer Prepare. The pressure is applied so that the first wire and the second wire are separated from each other around the bonding layer bonded to the first superconducting layer, including the portion where the first superconducting layer is bonded to the bonding layer.
　本開示の一態様に係る超電導コイルは、上記の超電導線を備える。超電導線は、超電導コイルの中心軸周りに巻き回されている。本開示の一態様に係る超電導機器は、上記の超電導コイルと、内部に上記の超電導コイルを格納するクライオスタットと、上記の超電導コイルを冷却する冷凍機とを備える。 A superconducting coil according to an aspect of the present disclosure includes the superconducting wire described above. The superconducting wire is wound around the central axis of the superconducting coil. A superconducting device according to an aspect of the present disclosure includes the superconducting coil, a cryostat that stores the superconducting coil therein, and a refrigerator that cools the superconducting coil.
図１は、第１実施形態に係る超電導線の上面図である。FIG. 1 is a top view of the superconducting wire according to the first embodiment. 図２は、図１のＩＩ－ＩＩにおける断面図である。FIG. 2 is a cross-sectional view taken along the line II-II in FIG. 図３は、図１のＩＩＩ－ＩＩＩにおける断面図である。3 is a cross-sectional view taken along line III-III in FIG. 図４は、図１のＩＶ－ＩＶにおける断面図である。4 is a cross-sectional view taken along line IV-IV in FIG. 図５は、第１実施形態に係る超電導線の接合方法を示す工程図である。FIG. 5 is a process diagram showing the superconducting wire joining method according to the first embodiment. 図６は、加熱加圧工程Ｓ３における接合部の断面図である。FIG. 6 is a cross-sectional view of the bonding portion in the heating and pressing step S3. 図７は、第２実施形態に係る超電導線の接合部における断面図である。FIG. 7 is a cross-sectional view of a superconducting wire joint according to the second embodiment. 図８は、第３実施形態に係る超電導線の上面図である。FIG. 8 is a top view of the superconducting wire according to the third embodiment. 図９は、図８のＩＸ－ＩＸにおける断面図である。FIG. 9 is a cross-sectional view taken along the line IX-IX in FIG. 図１０は、図８のＸ－Ｘにおける断面図である。10 is a cross-sectional view taken along the line XX of FIG. 図１１は、図８のＸＩ－ＸＩにおける断面図である。FIG. 11 is a cross-sectional view taken along the line XI-XI in FIG. 図１２は、超電導線を用いてコイルを形成した場合における磁場の状態を示す模式図である。FIG. 12 is a schematic diagram showing a state of a magnetic field when a coil is formed using a superconducting wire. 図１３は、図１２の領域ＸＩＩＩにおける拡大模式図である。FIG. 13 is an enlarged schematic view in a region XIII in FIG. 図１４は、第４実施形態に係る超電導機器の模式的な断面図である。FIG. 14 is a schematic cross-sectional view of a superconducting device according to the fourth embodiment.
　［本開示が解決しようとする課題］
　特許文献１に記載の超電導線において、接合層に酸素を導入する必要がある。しかしながら、特許文献１に記載の超電導線において、接合層は、端部を除いて外部雰囲気に対して露出していない。そのため、特許文献１に記載の超電導線においては、接合層に酸素を導入するための処理に長時間を要する。 [Problems to be solved by the present disclosure]
In the superconducting wire described in Patent Document 1, it is necessary to introduce oxygen into the bonding layer. However, in the superconducting wire described in Patent Document 1, the bonding layer is not exposed to the external atmosphere except for the end portions. Therefore, in the superconducting wire described in Patent Document 1, a long time is required for the treatment for introducing oxygen into the bonding layer.
　本開示は、このような従来技術の問題点に鑑みてなされたものである。具体的には、本開示は、接合層への酸素導入に要する時間を短縮することができる超電導線及び超電導線の接合方法を提供する。 The present disclosure has been made in view of such problems of the prior art. Specifically, the present disclosure provides a superconducting wire and a superconducting wire joining method that can reduce the time required to introduce oxygen into the joining layer.
　［本開示の効果］
　本開示の一態様に係る超電導線によると、接合層に酸素を導入するための処理に要する時間を短縮することができる。本開示の一態様に係る超電導線の接合方法によると、接合層に酸素を導入するための処理に要する時間を短縮することができる。本開示の一態様に係る超電導コイルによると、接合層に酸素を導入するための処理に要する時間を短縮することができる。本開示の一態様に係る超電導機器によると、接合層に酸素を導入するための処理に要する時間を短縮することができる。 [Effects of the present disclosure]
According to the superconducting wire according to one embodiment of the present disclosure, the time required for the treatment for introducing oxygen into the bonding layer can be shortened. According to the superconducting wire bonding method according to one embodiment of the present disclosure, the time required for the treatment for introducing oxygen into the bonding layer can be shortened. According to the superconducting coil according to one embodiment of the present disclosure, the time required for the treatment for introducing oxygen into the bonding layer can be shortened. According to the superconducting device according to one embodiment of the present disclosure, the time required for the treatment for introducing oxygen into the bonding layer can be shortened.
　［本開示の実施形態の説明］
　まず、本開示の実施態様を列記して説明する。 [Description of Embodiment of Present Disclosure]
First, embodiments of the present disclosure will be listed and described.
　（１）本開示の一態様に係る超電導線は、第１超電導層を有する第１線材と、第２超電導層と第２超電導層上に配置される接合層とを有し、かつ接合層が第１超電導層と対向するように配置される第２線材とを備える。第１超電導層、第２超電導層及び接合層を構成する材料は、高温超電導体である。第１超電導層は、接合層と超電導接合される部分を含む。第１超電導層と超電導接合される接合層の周囲において、第１線材と第２線材とは、互いに離間しながら重なり合う。 (1) A superconducting wire according to an aspect of the present disclosure includes a first wire having a first superconducting layer, a second superconducting layer, and a bonding layer disposed on the second superconducting layer, and the bonding layer is A second wire disposed to face the first superconducting layer. The material constituting the first superconducting layer, the second superconducting layer, and the bonding layer is a high-temperature superconductor. The first superconducting layer includes a portion that is superconductingly bonded to the bonding layer. The first wire and the second wire overlap each other while being spaced apart from each other around the bonding layer to be superconductively bonded to the first superconducting layer.
　上記（１）の超電導線においては、第１超電導層と超電導接合される接合層の周囲で、第１線材と第２線材とが離間している。酸素は、第１線材と第２線材との間を通過して、第１超電導層と超電導接合される接合層に供給される。そのため、上記（１）の超電導線によると、接合層に酸素を導入するための時間を短縮することができる。 In the superconducting wire of (1) above, the first wire and the second wire are separated around the bonding layer to be superconductingly bonded to the first superconducting layer. Oxygen passes between the first wire and the second wire and is supplied to the bonding layer that is superconductively bonded to the first superconducting layer. Therefore, according to the superconducting wire (1), the time for introducing oxygen into the bonding layer can be shortened.
　（２）上記（１）の超電導線において、第１超電導層は、第１線材の長手方向に沿って接合層と超電導接合されていてもよい。上記（２）の超電導線によると、接合層に酸素を導入するための時間を短縮することができる。 (2) In the superconducting wire of (1) above, the first superconducting layer may be superconductingly bonded to the bonding layer along the longitudinal direction of the first wire. According to the superconducting wire (2) above, the time for introducing oxygen into the bonding layer can be shortened.
　（３）上記（１）の超電導線において、第１超電導層の接合層側の面は、接合層と超電導接合している部分において周囲から突出していてもよい。上記（３）の超電導線によると、接合層に酸素を導入するための時間を短縮することができる。 (3) In the superconducting wire of the above (1), the surface of the first superconducting layer on the bonding layer side may protrude from the periphery at the portion where the superconducting bonding with the bonding layer is performed. According to the superconducting wire (3) above, the time for introducing oxygen into the bonding layer can be shortened.
　（４）上記（１）の超電導線において、第１超電導層は、第１線材の長手方向に沿って延在し、かつ第１線材の幅方向に沿って互いに分離された複数の部分によって構成されていてもよい。第２超電導層は、第２線材の長手方向に沿って延在し、かつ第２線材の幅方向に沿って互いに分離された複数の部分によって構成されていてもよい。 (4) In the superconducting wire of the above (1), the first superconducting layer is constituted by a plurality of portions extending along the longitudinal direction of the first wire and separated from each other along the width direction of the first wire. May be. The second superconducting layer may be constituted by a plurality of portions extending along the longitudinal direction of the second wire and separated from each other along the width direction of the second wire.
　上記（４）の超電導線においては、第１超電導及び第２超電導層の各々が、電気的に分離されている。そのため、上記（４）の超電導線を用いてコイルが形成された場合、当該コイルを流れる電流によって生じる磁場による遮蔽電流を低減することができる。 In the superconducting wire (4), each of the first superconducting layer and the second superconducting layer is electrically separated. Therefore, when a coil is formed using the superconducting wire of (4), it is possible to reduce the shielding current due to the magnetic field generated by the current flowing through the coil.
　（５）上記（１）～上記（５）の超電導線においては、高温超電導体は、ＲＥＢＣＯであってもよい。接合層の結晶方位は、第１超電導層及び第２超電導層の結晶方位に沿っていてもよい。上記（５）の超電導線材によると、接合層に酸素を導入するための時間を短縮することができる。 (5) In the superconducting wires of (1) to (5) above, the high-temperature superconductor may be REBCO. The crystal orientation of the bonding layer may be along the crystal orientation of the first superconducting layer and the second superconducting layer. According to the superconducting wire (5), the time for introducing oxygen into the bonding layer can be shortened.
　（６）本開示の一態様に係る超電導線の接合方法は、第１超電導層を有する第１線材と第２超電導層を有する第２線材とを準備する工程と、第２超電導層上に接合層を形成する工程と、第１超電導層と接合層とが対向した状態で、第１線材と第２線材との間に加熱しながら圧力を印加する工程と、接合層に酸素を導入する工程とを備える。圧力は、第１超電導層が接合層と接合される部分を含み、かつ第１超電導層に接合される接合層の周囲において第１線材と第２線材とが互いに離間するように印加される。 (6) A superconducting wire joining method according to one aspect of the present disclosure includes a step of preparing a first wire having a first superconducting layer and a second wire having a second superconducting layer, and joining on the second superconducting layer A step of forming a layer, a step of applying pressure while heating between the first wire and the second wire with the first superconducting layer and the bonding layer facing each other, and a step of introducing oxygen into the bonding layer With. The pressure is applied so that the first wire and the second wire are separated from each other around the bonding layer bonded to the first superconducting layer, including the portion where the first superconducting layer is bonded to the bonding layer.
　上記（６）の超電導線の接合方法によると、接合層に酸素を導入するための時間を短縮することができる。 According to the superconducting wire bonding method of (6) above, the time for introducing oxygen into the bonding layer can be shortened.
　（７）上記（６）の超電導線材の接合方法において、圧力は、第１線材及び第２線材を加圧治具で挟持するとともに、加圧治具と第１線材及び第２線材の少なくとも一方との間に板状部材を挿入することにより印加されてもよい。板状部材は、平面視において接合層に接合される第１超電導層と重なる位置に配置されていてもよい。上記（７）の超電導線の接合方法によると、接合層に酸素を導入するための時間を短縮することができる。 (7) In the superconducting wire joining method according to (6), the pressure is such that the first wire and the second wire are sandwiched by a pressure jig, and at least one of the pressure jig, the first wire, and the second wire. It may be applied by inserting a plate-like member between them. The plate-like member may be disposed at a position overlapping the first superconducting layer joined to the joining layer in plan view. According to the superconducting wire bonding method of (7) above, the time for introducing oxygen into the bonding layer can be shortened.
　（８）本開示の一態様に係る超電導コイルは、上記（１）～上記（５）の超電導線を備える。超電導線は、超電導コイルの中心軸周りに巻き回されている。 (8) A superconducting coil according to an aspect of the present disclosure includes the superconducting wires of (1) to (5) above. The superconducting wire is wound around the central axis of the superconducting coil.
　（９）本開示の一態様に係る超電導機器は、上記（８）の超電導コイルと、クライオスタットと、冷凍機とを備える。クライオスタットは、内部に超電導コイルを格納する。冷凍機は、超電導コイルを冷却する。 (9) A superconducting device according to an aspect of the present disclosure includes the superconducting coil according to (8), a cryostat, and a refrigerator. The cryostat houses a superconducting coil inside. The refrigerator cools the superconducting coil.
　［本開示の実施形態の詳細］
　次に、本開示に係る実施形態の詳細を、図面を参照して説明する。なお、各図中同一又は相当部分には同一符号を付している。また、以下に記載する実施の形態の少なくとも一部を任意に組み合わせてもよい。 [Details of Embodiment of the Present Disclosure]
Next, details of an embodiment according to the present disclosure will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals. Moreover, you may combine arbitrarily at least one part of embodiment described below.
　（第１実施形態）
　以下に、第１実施形態に係る超電導線の構成を説明する。 (First embodiment)
Below, the structure of the superconducting wire which concerns on 1st Embodiment is demonstrated.
　図１は、第１実施形態に係る超電導線の上面図である。図２は、図１のＩＩ－ＩＩにおける断面図である。図３は、図１のＩＩＩ－ＩＩＩにおける断面図である。図４は、図１のＩＶ－ＩＶにおける断面図である。 FIG. 1 is a top view of the superconducting wire according to the first embodiment. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. 3 is a cross-sectional view taken along line III-III in FIG. 4 is a cross-sectional view taken along line IV-IV in FIG.
　図１に示すように、第１実施形態に係る超電導線は、第１線材１と、第２線材２とを有している。第１線材１と第２線材２とは、互いに接合されている。第１線材１の長手方向は、第２線材２の長手方向に沿っていることが好ましい。なお、以下においては、第１線材１の長手方向（第２線材２の長手方向）に直交する方向を、第１線材１の幅方向（第２線材２の幅方向）ということがある。 As shown in FIG. 1, the superconducting wire according to the first embodiment has a first wire 1 and a second wire 2. The first wire 1 and the second wire 2 are joined together. The longitudinal direction of the first wire 1 is preferably along the longitudinal direction of the second wire 2. In the following, the direction orthogonal to the longitudinal direction of the first wire 1 (longitudinal direction of the second wire 2) may be referred to as the width direction of the first wire 1 (width direction of the second wire 2).
　図２に示すように、第１線材１は、第１超電導層１３を有している。より具体的には、第１線材１は、第１基材１１と、第１中間層１２と、第１超電導層１３と、第１保護層１４と、第１安定化層１５とを有している。 As shown in FIG. 2, the first wire 1 has a first superconducting layer 13. More specifically, the first wire 1 has a first base material 11, a first intermediate layer 12, a first superconducting layer 13, a first protective layer 14, and a first stabilization layer 15. ing.
　第１基材１１は、例えばステンレス鋼、ニッケル（Ｎｉ）層及び銅（Ｃｕ）層を積層したクラッド材により構成されている。第１基材１１は、ハステロイ（登録商標）等により構成されていてもよい。第１中間層１２は、第１基材１１上に配置されている。第１中間層１２は、第１基材１１と第１超電導層１３との格子ミスマッチを低減するための層である。第１中間層１２に用いられる材料は、第１超電導層１３に合わせて適宜選択される。第１超電導層１３がＲＥＢＣＯである場合、第１中間層１２は、例えば酸化セリウム（ＣｅＯ２）である。第１中間層１２は、一様な結晶配向を有していることが好ましい。 The first base material 11 is made of, for example, a clad material in which stainless steel, a nickel (Ni) layer, and a copper (Cu) layer are stacked. The first substrate 11 may be made of Hastelloy (registered trademark) or the like. The first intermediate layer 12 is disposed on the first base material 11. The first intermediate layer 12 is a layer for reducing lattice mismatch between the first base material 11 and the first superconducting layer 13. The material used for the first intermediate layer 12 is appropriately selected according to the first superconducting layer 13. When the first superconducting layer 13 is REBCO, the first intermediate layer 12 is, for example, cerium oxide (CeO 2 ). The first intermediate layer 12 preferably has a uniform crystal orientation.
　第１超電導層１３は、第１中間層１２上に配置されている。高温超電導体により構成されている。高温超電導体とは、超電導転移温度が液体窒素温度（７７ケルビン）以上となる材料をいう。第１超電導層１３を構成する高温超電導体は、例えばＲＥＢＣＯである。ＲＥＢＣＯは、（ＲＥ）Ｂａ２Ｃｕ３Ｏｘ（なお、ＲＥは、例えばイットリウム（Ｙ）、ガドリニウム（Ｇｄ）、ユーロピウム（Ｅｕ）、ジスプロシウム（Ｄｙ）、エルビウム（Ｅｒ）、ランタン（Ｌａ）、ツリウム（Ｔｍ）、イッテルビウム（Ｙｂ）等の希土類元素）により示される材料である。但し、第１超電導層１３を構成する材料は、これに限られない。第１超電導層１３を構成する材料は、例えばＢｉ２Ｓｒ２Ｃａ２Ｃｕ３Ｏｘ（Ｂｉ－２２２３）であってもよい。 The first superconducting layer 13 is disposed on the first intermediate layer 12. It is composed of a high-temperature superconductor. A high-temperature superconductor refers to a material having a superconducting transition temperature of liquid nitrogen temperature (77 Kelvin) or higher. The high temperature superconductor constituting the first superconducting layer 13 is, for example, REBCO. REBCO is (RE) Ba 2 Cu 3 O x (RE is, for example, yttrium (Y), gadolinium (Gd), europium (Eu), dysprosium (Dy), erbium (Er), lanthanum (La), thulium (Tm), rare earth elements such as ytterbium (Yb)). However, the material which comprises the 1st superconducting layer 13 is not restricted to this. The material constituting the first superconducting layer 13 may be, for example, Bi 2 Sr 2 Ca 2 Cu 3 O x (Bi-2223).
　第１超電導層１３は、一様な結晶配向性を有していることが好ましい。具体的には、第１超電導層１３を構成する材料のｃ軸が、第１中間層１２から第１保護層１４に向かう方向（第１超電導層１３の厚さ方向）に沿っていることが好ましい。このことを別の観点からいえば、第１超電導層１３を構成する材料のａｂ面が、第１線材１の長手方向及び幅方向と平行となっていることが好ましい。 The first superconducting layer 13 preferably has a uniform crystal orientation. Specifically, the c-axis of the material constituting the first superconducting layer 13 is along the direction from the first intermediate layer 12 toward the first protective layer 14 (the thickness direction of the first superconducting layer 13). preferable. From another viewpoint, it is preferable that the ab surface of the material constituting the first superconducting layer 13 is parallel to the longitudinal direction and the width direction of the first wire 1.
　第１保護層１４及び第１安定化層１５は、第１超電導層１３にクエンチ（超電導状態から通常電導状態に移行する現象）が生じた際に、電流をバイパスさせるための層である。第１保護層１４は、第１超電導層１３上に配置されている。第１安定化層１５は、第１保護層１４上に配置されている。第１保護層１４は、例えば銀（Ａｇ）等により構成されている。第１安定化層１５は、例えばＣｕ等により構成されている。 The first protective layer 14 and the first stabilization layer 15 are layers for bypassing current when a quench occurs in the first superconducting layer 13 (a phenomenon in which a transition from a superconducting state to a normal conducting state) occurs. The first protective layer 14 is disposed on the first superconducting layer 13. The first stabilization layer 15 is disposed on the first protective layer 14. The first protective layer 14 is made of, for example, silver (Ag). The first stabilization layer 15 is made of, for example, Cu.
　図３に示すように、第２線材２は、第２超電導層２３を有している。より具体的には、第２線材２は、第２基材２１と、第２中間層２２と、第２超電導層２３と、第２保護層２４と、第２安定化層２５とを有している。 As shown in FIG. 3, the second wire 2 has a second superconducting layer 23. More specifically, the second wire 2 has a second base material 21, a second intermediate layer 22, a second superconducting layer 23, a second protective layer 24, and a second stabilization layer 25. ing.
　第２基材２１は、例えばステンレス鋼、Ｎｉ層及びＣｕ層を積層したクラッド材により構成されている。第２基材２１は、ハステロイ（登録商標）等により構成されていてもよい。第２中間層２２は、第２基材２１上に配置されている。第２中間層２２は、第２基材２１と第２超電導層２３との格子ミスマッチを低減するための層である。第２中間層２２に用いられる材料は、第２超電導層２３に合わせて適宜選択される。第２超電導層２３がＲＥＢＣＯである場合、第２中間層２２は、例えばＣｅＯ２である。第２中間層２２は、一様な結晶配向を有していることが好ましい。 The 2nd base material 21 is comprised by the clad material which laminated | stacked stainless steel, Ni layer, and Cu layer, for example. The second base material 21 may be made of Hastelloy (registered trademark) or the like. The second intermediate layer 22 is disposed on the second base material 21. The second intermediate layer 22 is a layer for reducing lattice mismatch between the second base material 21 and the second superconducting layer 23. The material used for the second intermediate layer 22 is appropriately selected according to the second superconducting layer 23. When the second superconducting layer 23 is REBCO, second intermediate layer 22 is, for example, CeO 2. The second intermediate layer 22 preferably has a uniform crystal orientation.
　第２超電導層２３は、第２中間層２２上に配置されている。高温超電導体により構成されている。第２超電導層２３を構成する高温超電導体は、例えば、ＲＥＢＣＯである。なお、第２超電導層２３を構成する材料は、これに限られるものではない。第２超電導層２３を構成する材料は、例えば、Ｂｉ－２２２３であってもよい。第２超電導層２３を構成する高温超電導体は、第１超電導層１３を構成する高温超電導体と同一であることが好ましい。 The second superconducting layer 23 is disposed on the second intermediate layer 22. It is composed of a high-temperature superconductor. The high temperature superconductor constituting the second superconducting layer 23 is, for example, REBCO. In addition, the material which comprises the 2nd superconducting layer 23 is not restricted to this. The material constituting the second superconducting layer 23 may be, for example, Bi-2223. The high temperature superconductor constituting the second superconducting layer 23 is preferably the same as the high temperature superconductor constituting the first superconducting layer 13.
　第２超電導層２３は、一様な結晶配向性を有していることが好ましい。具体的には、第２超電導層２３を構成する材料のｃ軸が、第２中間層２２から第２保護層２４に向かう方向（第２超電導層２３の厚さ方向）に沿っていることが好ましい。このことを別の観点からいえば、第２超電導層２３を構成する材料のａｂ面が、第２線材２の長手方向及び幅方向と平行となっていることが好ましい。 The second superconducting layer 23 preferably has a uniform crystal orientation. Specifically, the c-axis of the material constituting the second superconducting layer 23 is along the direction from the second intermediate layer 22 toward the second protective layer 24 (the thickness direction of the second superconducting layer 23). preferable. From another viewpoint, it is preferable that the ab surface of the material constituting the second superconducting layer 23 is parallel to the longitudinal direction and the width direction of the second wire 2.
　第２保護層２４及び第２安定化層２５は、第２超電導層２３にクエンチが生じた際に電流をバイパスさせるための層である。第２保護層２４は、第２超電導層２３上に配置されている。第２安定化層２５は、第２保護層２４上に配置されている。第２保護層２４は、例えばＡｇ等により構成されている。第２安定化層２５は、例えばＣｕ等により構成されている。 The second protective layer 24 and the second stabilization layer 25 are layers for bypassing current when the second superconducting layer 23 is quenched. The second protective layer 24 is disposed on the second superconducting layer 23. The second stabilization layer 25 is disposed on the second protective layer 24. The second protective layer 24 is made of, for example, Ag. The second stabilization layer 25 is made of, for example, Cu.
　図４に示すように、第２線材２は、接合層３をさらに有している。第１線材１と第２線材２とが接合されている部分においては、第１保護層１４、第１安定化層１５、第２保護層２４及び第２安定化層２５は除去されている。接合層３は、第２超電導層２３上に配置されている。第１線材１と第２線材２とが接合されている部分においては、第１線材１と第２線材２とは、第１超電導層１３と接合層３とが対向するように配置されている。 As shown in FIG. 4, the second wire 2 further has a bonding layer 3. In the portion where the first wire 1 and the second wire 2 are joined, the first protective layer 14, the first stabilizing layer 15, the second protective layer 24, and the second stabilizing layer 25 are removed. The bonding layer 3 is disposed on the second superconducting layer 23. In the portion where the first wire 1 and the second wire 2 are joined, the first wire 1 and the second wire 2 are arranged so that the first superconducting layer 13 and the joining layer 3 face each other. .
　接合層３は、高温超電導体により構成されている。好ましくは、接合層３を構成する高温超電導体は、第１超電導層１３及び第２超電導層２３を構成する高温超電導体と同一である。接合層３は、第１部分３ａと、第２部分３ｂと、第３部分３ｃとを有している。第２部分３ｂは、第１部分３ａと離間している。第１部分３ａ及び第２部分３ｂは、例えば第２線材２の幅方向における両端に位置している。第３部分３ｃは、第１部分３ａと第２部分３ｂとに挟み込まれている。 The bonding layer 3 is composed of a high-temperature superconductor. Preferably, the high temperature superconductor constituting the bonding layer 3 is the same as the high temperature superconductor constituting the first superconductor layer 13 and the second superconductor layer 23. The bonding layer 3 includes a first portion 3a, a second portion 3b, and a third portion 3c. The second part 3b is separated from the first part 3a. The first portion 3 a and the second portion 3 b are located at both ends in the width direction of the second wire 2, for example. The third portion 3c is sandwiched between the first portion 3a and the second portion 3b.
　第３部分３ｃは、第１超電導層１３と超電導接合されている。第１部分３ａ及び第２部分３ｂは、第１超電導層１３と接合されていない（第１超電導層１３と離間している）。このことを別の観点からいえば、接合層３は、第１超電導層１３と超電導接合されている接合層３の周囲において、第１線材１と第２線材２とは、互いに離間しながら重なり合っている。なお、接合層３は、第１部分３ａ、第２部分３ｂ及び第３部分３ｃにおいて、第２超電導層２３と超電導接合されていることが好ましい。 The third portion 3c is superconductively joined to the first superconducting layer 13. The first portion 3a and the second portion 3b are not joined to the first superconducting layer 13 (separated from the first superconducting layer 13). From another viewpoint, the bonding layer 3 is overlapped with the first wire 1 and the second wire 2 being separated from each other around the bonding layer 3 that is superconductively bonded to the first superconductive layer 13. ing. Note that the bonding layer 3 is preferably superconductively bonded to the second superconducting layer 23 in the first portion 3a, the second portion 3b, and the third portion 3c.
　ここで、第１超電導層１３（第２超電導層２３）が接合層３とが超電導接合されているとは、第１超電導層１３（第２超電導層２３）の超電導転移温度以下の温度において、第１超電導層１３（第２超電導層２３）と接合層３との間を、電流が超電導状態で流れることをいう。 Here, the first superconducting layer 13 (second superconducting layer 23) and the joining layer 3 are superconductingly joined at a temperature not higher than the superconducting transition temperature of the first superconducting layer 13 (second superconducting layer 23). It means that current flows between the first superconducting layer 13 (second superconducting layer 23) and the bonding layer 3 in a superconducting state.
　第１部分３ａ、第２部分３ｂ及び第３部分３ｃは、第１線材１及び第２線材２の長手方向に沿って延在していることが好ましい。すなわち、接合層３は、第１線材１及び第２線材２の長手方向に沿って第１超電導層１３と超電導接合されていることが好ましい。第１部分３ａは、幅Ｗ１を有している。第２部分３ｂは、幅Ｗ２を有している。第３部分３ｃは、幅Ｗ３を有している。幅Ｗ１は、第１線材１及び第２線材２の幅方向における第１部分３ａの幅である。幅Ｗ２は、第１線材１及び第２線材２の幅方向における第２部分３ｂの幅である。幅Ｗ３は、第１線材１及び第２線材２の幅方向における第３部分３ｃの幅である。好ましくは、幅Ｗ３を幅Ｗ１と幅Ｗ２との和で除した値は、０．１３以上０．７５以下である。 It is preferable that the first portion 3a, the second portion 3b, and the third portion 3c extend along the longitudinal direction of the first wire 1 and the second wire 2. That is, the bonding layer 3 is preferably superconductively bonded to the first superconducting layer 13 along the longitudinal direction of the first wire 1 and the second wire 2. The first portion 3a has a width W1. The second portion 3b has a width W2. The third portion 3c has a width W3. The width W <b> 1 is the width of the first portion 3 a in the width direction of the first wire 1 and the second wire 2. The width W <b> 2 is the width of the second portion 3 b in the width direction of the first wire 1 and the second wire 2. The width W <b> 3 is the width of the third portion 3 c in the width direction of the first wire 1 and the second wire 2. Preferably, a value obtained by dividing the width W3 by the sum of the width W1 and the width W2 is 0.13 or more and 0.75 or less.
　なお、上記においては、第１線材１と第２線材２とが重ね合わされて超電導接合されている場合について説明したが、第１線材１の一方端と他方端とが重ね合わされて超電導接合されていてもよい。すなわち、第１超電導層１３は、第１線材１の一方端において第１端部を有し、第１線材１の他方端において第２端部を有していてもよい。他方端に位置する第１線材１は、第２端部上に接合層３を有していてもよい。接合層３は、第１端部と対向していてもよい。第１端部は、接合層３と超電導接合されている部分を有していてもよい。接合層３と超電導接合されている第１端部の周囲において、第１線材１の一方端と他方端とは、互いに離間しながら重なり合っていてもよい。 In the above description, the case where the first wire 1 and the second wire 2 are superposed and superconducting joined has been described, but one end and the other end of the first wire 1 are superposed and superconducting joined. May be. That is, the first superconducting layer 13 may have a first end at one end of the first wire 1 and a second end at the other end of the first wire 1. The first wire 1 positioned at the other end may have a bonding layer 3 on the second end. The bonding layer 3 may face the first end. The first end portion may have a portion that is superconductively bonded to the bonding layer 3. Around the first end portion that is superconductingly bonded to the bonding layer 3, the one end and the other end of the first wire 1 may overlap with each other while being separated from each other.
　以下に、第１実施形態に係る超電導線の接合方法を説明する。
　図５は、第１実施形態に係る超電導線の接合方法を示す工程図である。図５に示すように、第１実施形態に係る超電導線の接合方法は、線材準備工程Ｓ１と、接合層形成工程Ｓ２と、加熱加圧工程Ｓ３と、接合層酸素導入工程Ｓ４とを有している。 The superconducting wire joining method according to the first embodiment will be described below.
FIG. 5 is a process diagram showing the superconducting wire joining method according to the first embodiment. As shown in FIG. 5, the superconducting wire bonding method according to the first embodiment includes a wire rod preparation step S1, a bonding layer forming step S2, a heating and pressing step S3, and a bonding layer oxygen introduction step S4. ing.
　線材準備工程Ｓ１においては、第１線材１及び第２線材２の準備が行われる。接合層形成工程Ｓ２においては、接合層３の形成が行われる。接合層３は、第２超電導層２３上に形成される。 In the wire preparation step S1, the first wire 1 and the second wire 2 are prepared. In the bonding layer forming step S2, the bonding layer 3 is formed. The bonding layer 3 is formed on the second superconducting layer 23.
　接合層３の形成には、第１に、接合層３に用いられる高温超電導体を構成する元素の有機化合物が塗布される。第２に、この有機化合物の塗膜に対する熱処理が行われる。これにより、この有機化合物の塗膜は、接合層３に用いられる高温超電導体の前駆体（以下においては、この前駆体を含む膜を、仮焼膜という）となる。この前駆体は、接合層３に用いられる高温超電導体を構成する元素の炭化物を含んでいる。なお、この熱処理は、この有機化合物の分解温度以上接合層３に用いられる高温超電導体の生成温度未満の処理温度において行われる。 In forming the bonding layer 3, first, an organic compound of an element constituting the high-temperature superconductor used in the bonding layer 3 is applied. Secondly, a heat treatment is performed on the coating film of the organic compound. Thereby, the coating film of the organic compound becomes a precursor of the high-temperature superconductor used for the bonding layer 3 (hereinafter, a film containing the precursor is referred to as a calcined film). This precursor contains carbides of elements constituting the high-temperature superconductor used for the bonding layer 3. This heat treatment is performed at a treatment temperature that is equal to or higher than the decomposition temperature of the organic compound and lower than the generation temperature of the high-temperature superconductor used in the bonding layer 3.
　第３に、仮焼膜に対する熱処理が行われる。これにより、仮焼膜に含まれる炭化物が分解して接合層３に用いられる高温超電導体となる。なお、仮焼膜に対する熱処理は、１パーセント以上の酸素濃度の雰囲気下において行われる。この段階において、接合層３は、高温超電導体の微細な結晶を含んでいる。 Third, a heat treatment is performed on the calcined film. Thereby, the carbide contained in the calcined film is decomposed to become a high-temperature superconductor used for the bonding layer 3. Note that the heat treatment for the calcined film is performed in an atmosphere having an oxygen concentration of 1 percent or more. At this stage, the bonding layer 3 contains fine crystals of the high-temperature superconductor.
　図６は、加熱加圧工程Ｓ３における接合部の断面図である。図６に示すように、加熱加圧工程Ｓ３においては、第１線材１及び第２線材２は、接合層３と第１超電導層１３とが対向するように配置されている。加熱加圧工程Ｓ３においては、第１線材１と第２線材との間に（より具体的には、第１超電導層１３と第２超電導層２３との間に）圧力が印加される。この圧力の印加に際しては、加熱も行われる。 FIG. 6 is a cross-sectional view of the joint portion in the heating and pressing step S3. As shown in FIG. 6, in the heating and pressurizing step S3, the first wire 1 and the second wire 2 are arranged so that the bonding layer 3 and the first superconducting layer 13 face each other. In the heating and pressurizing step S3, pressure is applied between the first wire 1 and the second wire (more specifically, between the first superconducting layer 13 and the second superconducting layer 23). In applying this pressure, heating is also performed.
　この圧力は、第１超電導層１３が接合層３と接合される部分を含み、かつ第１超電導層１３に接合される接合層３の周囲において第１線材１と第２線材２とが互いに離間するように印加される。 This pressure includes a portion where the first superconducting layer 13 is joined to the joining layer 3, and the first wire 1 and the second wire 2 are separated from each other around the joining layer 3 joined to the first superconducting layer 13. To be applied.
　より具体的には、この圧力の印加は、第１線材１及び第２線材２を加圧治具４で挟持するとともに、加圧治具４と第１線材１及び第２線材２の少なくとも一方との間に加圧調整板５を挟み込むことによって行われる。加圧調整板５は、板状の部材である。加圧調整板５は、平面視において、接合層３と接合される第１超電導層１３と重なる位置に配置される。 More specifically, the pressure is applied by holding the first wire 1 and the second wire 2 with the pressure jig 4 and at least one of the pressure jig 4, the first wire 1 and the second wire 2. The pressure adjustment plate 5 is sandwiched between the two. The pressure adjusting plate 5 is a plate-like member. The pressure adjusting plate 5 is disposed at a position overlapping the first superconducting layer 13 bonded to the bonding layer 3 in plan view.
　平面視において加圧調整板５と重なる部分においては、第１超電導層１３と第２超電導層２３との間に加わる圧力が大きくなる。その結果、接合層３に含まれている高温超電導体の微細な結晶が、第１超電導層１３及び第２超電導層２３の結晶方位に沿ってエピタキシャル成長する。他方で、平面視において加圧調整板５と重ならない部分においては、第１超電導層１３と第２超電導層２３との間に加わる圧力が相対的に小さい。そのため、接合層に含まれている高温超電導体の微細な結晶は、第２超電導層２３の結晶方位に沿ってエピタキシャル成長するが、第１超電導層１３の結晶方位に沿ってエピタキシャル成長しない。すなわち、平面視において加圧調整板５と重なる部分において、接合層３と第１超電導層１３との超電導接合が達成されるが、平面視において加圧調整板５と重ならない部分において、接合層３と第１超電導層１３との接合が達成されない。 The pressure applied between the first superconducting layer 13 and the second superconducting layer 23 increases in a portion overlapping the pressure adjusting plate 5 in plan view. As a result, fine crystals of the high-temperature superconductor contained in the bonding layer 3 are epitaxially grown along the crystal orientations of the first superconducting layer 13 and the second superconducting layer 23. On the other hand, the pressure applied between the first superconducting layer 13 and the second superconducting layer 23 is relatively small in a portion that does not overlap the pressure adjusting plate 5 in plan view. Therefore, the fine crystals of the high-temperature superconductor contained in the bonding layer are epitaxially grown along the crystal orientation of the second superconducting layer 23, but not epitaxially grown along the crystal orientation of the first superconducting layer 13. That is, superconducting bonding between the bonding layer 3 and the first superconducting layer 13 is achieved in a portion overlapping the pressure adjusting plate 5 in a plan view, but in a portion not overlapping the pressure adjusting plate 5 in a plan view. 3 and the first superconducting layer 13 are not joined.
　接合層酸素導入工程Ｓ４においては、接合層３への酸素が導入される。具体的には、第１線材１、第２線材２及び接合層３が、酸素を含有する雰囲気中において熱処理を受けることにより、接合層へ酸素が導入される。以上により、第１実施形態に係る超電導線の接合方法が完了する。 In the bonding layer oxygen introduction step S4, oxygen is introduced into the bonding layer 3. Specifically, the first wire 1, the second wire 2, and the bonding layer 3 are subjected to heat treatment in an atmosphere containing oxygen, whereby oxygen is introduced into the bonding layer. Thus, the superconducting wire joining method according to the first embodiment is completed.
　以下に、第１実施形態に係る超電導線及び第１実施形態に係る超電導線の接合方法の効果を説明する。 Hereinafter, effects of the superconducting wire according to the first embodiment and the superconducting wire joining method according to the first embodiment will be described.
　第１実施形態に係る超電導線においては、第１部分３ａ及び第２部分３ｂが第１超電導層１３と接合していない。そのため、酸素は、第１部分３ａ及び第２部分３ｂと第１超電導層１３との間を通過して、第１超電導層１３と接合されている第３部分３ｃに供給される。このように、第１実施形態に係る超電導線及び第１実施形態に係る超電導線の接合方法によると、超電導接合に寄与する接合層に酸素を供給するための経路が確保されているため、接合層３に酸素を導入するための時間を短縮することができる。 In the superconducting wire according to the first embodiment, the first portion 3 a and the second portion 3 b are not joined to the first superconducting layer 13. Therefore, oxygen passes between the first part 3 a and the second part 3 b and the first superconducting layer 13 and is supplied to the third part 3 c joined to the first superconducting layer 13. As described above, according to the superconducting wire according to the first embodiment and the superconducting wire joining method according to the first embodiment, a path for supplying oxygen to the joining layer contributing to the superconducting junction is secured. The time for introducing oxygen into the layer 3 can be shortened.
　（第２実施形態）
　以下に、第２実施形態に係る超電導線を、図面を参照して説明する。なお、以下においては、第１実施形態に係る超電導線と異なる点を主に説明し、重複する説明については繰り返さない。 (Second Embodiment)
The superconducting wire according to the second embodiment will be described below with reference to the drawings. In the following, differences from the superconducting wire according to the first embodiment will be mainly described, and overlapping description will not be repeated.
　図７は、第２実施形態に係る超電導線の接合部における断面図である。図７に示すように、第２実施形態に係る超電導線は、第１線材１と、第２線材２とを有している。第１線材１は、第１超電導層１３を有している。第２線材２は、第２超電導層２３と、接合層３とを有している。接合層３は、第１部分３ａと、第２部分３ｂと、第３部分３ｃとを有している。第１超電導層１３は、第３部分３ｃに超電導接合されている。第１線材１は、第１部分３ａ及び第２部分３ｂと離間している。すなわち、第１超電導層１３は、接合層３と超電導接合している部分を有し、第１超電導層１３と超電導接合している接合層３の周囲において、第１線材１と第２線材２とは、互いに離間しながら重なり合っている。これらの点において、第２実施形態に係る超電導線は、第１実施形態に係る超電導線と共通している。 FIG. 7 is a cross-sectional view at the junction of the superconducting wire according to the second embodiment. As shown in FIG. 7, the superconducting wire according to the second embodiment has a first wire 1 and a second wire 2. The first wire 1 has a first superconducting layer 13. The second wire 2 has a second superconducting layer 23 and a bonding layer 3. The bonding layer 3 includes a first portion 3a, a second portion 3b, and a third portion 3c. The first superconducting layer 13 is superconductingly joined to the third portion 3c. The first wire 1 is separated from the first part 3a and the second part 3b. That is, the first superconducting layer 13 has a portion that is superconductively bonded to the bonding layer 3, and the first wire 1 and the second wire 2 around the bonding layer 3 that is superconductively bonded to the first superconductive layer 13. And overlap each other while being separated from each other. In these respects, the superconducting wire according to the second embodiment is common to the superconducting wire according to the first embodiment.
　第１超電導層１３は、第１面１３ａと第２面１３ｂとを有している。第２面１３ｂは、第１面１３ａの反対面である。第２面１３ｂは、第１中間層１２側の面である。第１面１３ａは、接合層３側の面である。第１面１３ａは、第３部分３ｃに対向している部分において、第２面１３ｂ側に向かって突出している。すなわち、第１面１３ａは、接合層３と超電導接合している部分において、周囲から突出している。この点において、第２実施形態に係る超電導線は、第１実施形態に係る超電導線と異なっている。 The first superconducting layer 13 has a first surface 13a and a second surface 13b. The second surface 13b is the opposite surface of the first surface 13a. The second surface 13b is a surface on the first intermediate layer 12 side. The first surface 13a is a surface on the bonding layer 3 side. The first surface 13a protrudes toward the second surface 13b at the portion facing the third portion 3c. That is, the first surface 13a protrudes from the periphery at a portion where the first conductive layer 13a and the bonding layer 3 are superconductively bonded. In this regard, the superconducting wire according to the second embodiment is different from the superconducting wire according to the first embodiment.
　第２実施形態に係る超電導線においては、第１部分３ａ及び第２部分３ｂと第１面１３ａとの間に空間が形成される。第１超電導層１３と超電導接合されている第３部分３ｃには、この空間を介して、酸素が供給される。そのため、第２実施形態に係る超電導線によると、第１実施形態に係る超電導線と同様に、超電導接合に寄与する接合層３に酸素を導入するための時間を短縮することができる。 In the superconducting wire according to the second embodiment, a space is formed between the first portion 3a and the second portion 3b and the first surface 13a. Oxygen is supplied to the third portion 3c that is superconductingly bonded to the first superconducting layer 13 through this space. Therefore, according to the superconducting wire according to the second embodiment, the time for introducing oxygen into the bonding layer 3 that contributes to the superconducting junction can be shortened, similarly to the superconducting wire according to the first embodiment.
　（第３実施形態）
　以下に、第３実施形態に係る超電導線を、図面を参照して説明する。なお、以下においては、第１実施形態に係る超電導線と異なる点を主に説明し、重複する説明については繰り返さない。 (Third embodiment)
The superconducting wire according to the third embodiment will be described below with reference to the drawings. In the following, differences from the superconducting wire according to the first embodiment will be mainly described, and overlapping description will not be repeated.
　図８は、第３実施形態に係る超電導線の上面図である。図８に示すように、第３実施形態に係る超電導線は、第１線材１と、第２線材２とを有している。図９は、図８のＩＸ－ＩＸにおける断面図である。図１０は、図８のＸ－Ｘにおける断面図である。図１１は、図８のＸＩ－ＸＩにおける断面図である。図９に示すように、第１線材１は、第１超電導層１３を有している。図１０に示すように、第２線材２は、第２超電導層２３を有している。 FIG. 8 is a top view of the superconducting wire according to the third embodiment. As shown in FIG. 8, the superconducting wire according to the third embodiment has a first wire 1 and a second wire 2. FIG. 9 is a cross-sectional view taken along the line IX-IX in FIG. 10 is a cross-sectional view taken along the line XX of FIG. FIG. 11 is a cross-sectional view taken along the line XI-XI in FIG. As shown in FIG. 9, the first wire 1 has a first superconducting layer 13. As shown in FIG. 10, the second wire 2 has a second superconducting layer 23.
　図１１に示すように、第２線材２は、さらに接合層３を有している。第１超電導層１３は、第３部分３ｃと超電導接合している。第１線材１は、第１部分３ａ及び第２部分３ｂと対向する部分において、第２線材２と離間しながら重なり合っている。すなわち、第１超電導層１３は、接合層３と超電導接合している部分を有し、第１超電導層１３と超電導接合している接合層３の周囲において、第１線材１と第２線材２とは、互いに離間しながら重なりあっている。これらの点において、第３実施形態に係る超電導線は、第１実施形態に係る超電導線と共通している。 As shown in FIG. 11, the second wire 2 further has a bonding layer 3. The first superconducting layer 13 is in superconducting junction with the third portion 3c. The first wire 1 is overlapped while being separated from the second wire 2 at a portion facing the first portion 3a and the second portion 3b. That is, the first superconducting layer 13 has a portion that is superconductively bonded to the bonding layer 3, and the first wire 1 and the second wire 2 around the bonding layer 3 that is superconductively bonded to the first superconductive layer 13. And overlap each other while being separated from each other. In these respects, the superconducting wire according to the third embodiment is common to the superconducting wire according to the first embodiment.
　第１超電導層１３は、第１線材１の長手方向に沿って延在し、かつ、第１線材１の幅方向に沿って間隔を置いて配置される複数の部分により構成されている。第２超電導層２３は、第２線材２の長手方向に沿って延在し、かつ第２線材２の幅方向に沿って間隔を置いて配置される複数の部分により構成されている。これらの点において、第３実施形態に係る超電導線は、第１実施形態に係る超電導線と異なっている。なお、第１超電導層１３の複数の部分の各々は、第２超電導層２３の複数の部分の各々と接合層３（第３部分３ｃ）を介して対向している。 The first superconducting layer 13 is constituted by a plurality of portions extending along the longitudinal direction of the first wire 1 and arranged at intervals along the width direction of the first wire 1. The second superconducting layer 23 is composed of a plurality of portions that extend along the longitudinal direction of the second wire 2 and are arranged at intervals along the width direction of the second wire 2. In these respects, the superconducting wire according to the third embodiment is different from the superconducting wire according to the first embodiment. Each of the plurality of portions of the first superconducting layer 13 opposes each of the plurality of portions of the second superconducting layer 23 via the bonding layer 3 (third portion 3c).
　図１２は、超電導線を用いてコイルを形成した場合における磁場の状態を示す模式図である。図１２に示すように、コイル２０に電流が流れることにより磁場ＭＦが生じる。この磁場ＭＦは、コイル径方向における成分ＭＦ１と、コイル長方向における成分ＭＦ２とを有している。 FIG. 12 is a schematic diagram showing the state of a magnetic field when a coil is formed using a superconducting wire. As shown in FIG. 12, a magnetic field MF is generated when a current flows through the coil 20. This magnetic field MF has a component MF1 in the coil radial direction and a component MF2 in the coil length direction.
　図１３は、図１２の領域ＸＩＩＩにおける拡大模式図である。図１３に示すように、コイル２０を構成する超電導線は、超電導層１０を有している。超電導層１０は、超電導線中において一様に形成されている。超電導層１０には、コイル径方向における成分ＭＦ１により、渦電流（遮蔽電流）が生じる。この遮蔽電流によりさらに磁場が生じる。その結果、コイル２０の中心磁場が減少する、コイル２０の中心磁場が時間変動する、コイル２０の磁場分布が編成するといった問題が生じる。 FIG. 13 is an enlarged schematic diagram in region XIII of FIG. As shown in FIG. 13, the superconducting wire constituting the coil 20 has a superconducting layer 10. Superconducting layer 10 is uniformly formed in the superconducting wire. In the superconducting layer 10, an eddy current (shielding current) is generated by the component MF1 in the coil radial direction. This shielding current further generates a magnetic field. As a result, there arise problems that the central magnetic field of the coil 20 decreases, the central magnetic field of the coil 20 varies with time, and the magnetic field distribution of the coil 20 is organized.
　第３実施形態に係る超電導線においては、第１超電導層１３は、第１線材１の長手方向に沿って延在し、かつ第１線材１の幅方向に沿って間隔を置いて配置される複数の部分により構成されている。第２超電導層２３は、第２線材２の長手方向に沿って延在し、かつ第２線材２の幅方向に沿って間隔を置いて配置される複数の部分により構成されている。そのため、第１超電導層１３及び第２超電導層２３を構成する各々の部分が電気的に分離され、上記のような遮蔽電流が生じにくい。 In the superconducting wire according to the third embodiment, the first superconducting layer 13 extends along the longitudinal direction of the first wire 1 and is arranged at intervals along the width direction of the first wire 1. It is composed of a plurality of parts. The second superconducting layer 23 is composed of a plurality of portions that extend along the longitudinal direction of the second wire 2 and are arranged at intervals along the width direction of the second wire 2. Therefore, each part which comprises the 1st superconducting layer 13 and the 2nd superconducting layer 23 is electrically isolate | separated, and it is hard to produce the above shielding current.
　第３実施形態に係る超電導線において、第１超電導層１３は、第３部分３ｃと超電導接合している。また、第３実施形態に係る超電導線においては、第１線材１は、第１部分３ａ及び第２部分３ｂと対向する部分において、第２線材２から離間しながら重なりあっている。そのため、第１超電導層１３と接合している接合層３には、第１部分３ａ及び第２部分３ｂと第１線材１との間を介して酸素が供給される。したがって、第３実施形態に係る超電導線によると、第１実施形態に係る超電導線と同様に、超電導接合に寄与する接合層３に酸素を導入するための時間を短縮することができる。 In the superconducting wire according to the third embodiment, the first superconducting layer 13 is superconductingly joined to the third portion 3c. Further, in the superconducting wire according to the third embodiment, the first wire 1 is overlapped while being separated from the second wire 2 at a portion facing the first portion 3a and the second portion 3b. Therefore, oxygen is supplied to the bonding layer 3 bonded to the first superconducting layer 13 through the first wire 3 and the first wire 3 between the first portion 3 a and the second portion 3 b. Therefore, according to the superconducting wire according to the third embodiment, similarly to the superconducting wire according to the first embodiment, the time for introducing oxygen into the bonding layer 3 that contributes to the superconducting junction can be shortened.
　（第４実施形態）
　以下に、第４実施形態に係る超電導機器を、図面を参照して説明する。 (Fourth embodiment)
The superconducting device according to the fourth embodiment will be described below with reference to the drawings.
　図１４は、第４実施形態に係る超電導機器の模式的な断面図である。図１４に示すように、第４実施形態に係る超電導機器は、超電導コイル１１０と、クライオスタット１２０と、冷凍機１３０とを有している。超電導コイル１１０は、クライオスタット１２０の内部に配置されている。より具体的には、クライオスタット１２０の内部に熱シールド１２１が配置されており、熱シールド１２１の内部に超電導コイル１１０が配置されている。超電導コイル１１０は、超電導線１１１が超電導コイル１１０の中心軸周りに巻き回されることにより形成されている。超電導線１１１は、上記の第１ないし第３実施形態に係る超電導線である。 FIG. 14 is a schematic cross-sectional view of a superconducting device according to the fourth embodiment. As shown in FIG. 14, the superconducting device according to the fourth embodiment includes a superconducting coil 110, a cryostat 120, and a refrigerator 130. Superconducting coil 110 is disposed inside cryostat 120. More specifically, the heat shield 121 is disposed inside the cryostat 120, and the superconducting coil 110 is disposed inside the heat shield 121. Superconducting coil 110 is formed by winding superconducting wire 111 around the central axis of superconducting coil 110. The superconducting wire 111 is a superconducting wire according to the first to third embodiments.
　冷凍機１３０は、クライオスタット１２０の内部に配置されている超電導コイル１１０を、第１超電導層１３及び第２超電導層２３の超電導転移温度以下に冷却する。冷凍機１３０は、例えばギフォード・マクマホン式冷凍機である。 The refrigerator 130 cools the superconducting coil 110 disposed inside the cryostat 120 to the superconducting transition temperature of the first superconducting layer 13 and the second superconducting layer 23 or lower. The refrigerator 130 is, for example, a Gifford McMahon refrigerator.
　今回開示された実施の形態は全ての点で例示であって、制限的なものではないと考えられるべきである。本発明の範囲は上記した実施形態ではなく請求の範囲によって示され、請求の範囲と均等の意味、及び範囲内での全ての変更が含まれることが意図される。 The embodiment disclosed herein is illustrative in all respects and should not be considered as restrictive. The scope of the present invention is shown not by the above-described embodiments but by the scope of claims, and is intended to include meanings equivalent to the scope of claims and all modifications within the scope.
１　第１線材、１１　第１基材、１２　第１中間層、１３　第１超電導層、１３ａ　第１面、１３ｂ　第２面、１４　第１保護層、１５　第１安定化層、２　第２線材、２１　第２基材、２２　第２中間層、２３　第２超電導層、２４　第２保護層、２５　第２安定化層、３　接合層、３ａ　第１部分、３ｂ　第２部分、３ｃ　第３部分、４　加圧治具、５　加圧調整板、１０　超電導層、２０　コイル、１１０　超電導コイル、１１１　超電導線、１２０　クライオスタット、１２１　熱シールド、１３０　冷凍機、ＭＦ　磁場、ＭＦ１，ＭＦ２　成分、Ｐ１，Ｐ２　圧力、Ｓ１　線材準備工程、Ｓ２　接合層形成工程、Ｓ３　加熱加圧工程、Ｓ４　接合層酸素導入工程、Ｗ１，Ｗ２，Ｗ３　幅。 DESCRIPTION OF SYMBOLS 1 1st wire, 11 1st base material, 12 1st intermediate | middle layer, 13 1st superconducting layer, 13a 1st surface, 13b 2nd surface, 14 1st protective layer, 15 1st stabilization layer, 2nd 2nd wire , 21 second substrate, 22 second intermediate layer, 23 second superconducting layer, 24 second protective layer, 25 second stabilizing layer, 3 bonding layer, 3a first part, 3b second part, 3c third part 4, pressurizing jig, 5 pressurizing adjustment plate, 10 superconducting layer, 20 coil, 110 superconducting coil, 111 superconducting wire, 120 cryostat, 121 heat shield, 130 refrigerator, MF magnetic field, MF1, MF2 component, P1, P2 Pressure, S1 wire preparation step, S2 bonding layer formation step, S3 heating and pressurization step, S4 bonding layer oxygen introduction step, W1, W2, W3 width.

Claims (9)

  1. 　第１超電導層を有する第１線材と、
    　第２超電導層と、前記第２超電導層上に配置される接合層とを有し、かつ前記接合層が前記第１超電導層と対向するように配置される第２線材とを備え、
    　前記第１超電導層、前記第２超電導層及び前記接合層を構成する材料は、高温超電導体であり、
    　前記第１超電導層は、前記接合層と超電導接合される部分を含み、
    　前記第１超電導層と超電導接合される前記接合層の周囲において、前記第１線材と前記第２線材とは、互いに離間しながら重なり合う、超電導線。     A first wire having a first superconducting layer;
    A second superconducting layer, and a second wire having a bonding layer disposed on the second superconducting layer and disposed so that the bonding layer faces the first superconducting layer,
    The material constituting the first superconducting layer, the second superconducting layer, and the bonding layer is a high-temperature superconductor,
    The first superconducting layer includes a portion to be superconductingly bonded to the bonding layer,
    A superconducting wire in which the first wire and the second wire overlap each other while being spaced apart from each other around the joining layer to be superconductingly joined to the first superconducting layer.
  2. 　前記第１超電導層は、前記第１線材の長手方向に沿って前記接合層と超電導接合される、請求項１に記載の超電導線。 The superconducting wire according to claim 1, wherein the first superconducting layer is superconductingly joined to the joining layer along a longitudinal direction of the first wire.
  3. 　前記第１超電導層の前記接合層側の面は、前記接合層と超電導接合している部分において、周囲から突出している、請求項１に記載の超電導線。 The superconducting wire according to claim 1, wherein a surface of the first superconducting layer on the side of the joining layer protrudes from the periphery at a portion where the superconducting joining with the joining layer is performed.
  4. 　前記第１超電導層は、前記第１線材の長手方向に沿って延在し、かつ前記第１線材の幅方向に沿って互いに分離された複数の部分によって構成され、
    　前記第２超電導層は、前記第２線材の長手方向に沿って延在し、かつ前記第２線材の幅方向に沿って互いに分離された複数の部分によって構成される、請求項１に記載の超電導線。     The first superconducting layer is configured by a plurality of portions extending along a longitudinal direction of the first wire and separated from each other along a width direction of the first wire,
    The said 2nd superconducting layer is comprised by the some part extended along the longitudinal direction of the said 2nd wire, and isolate | separated mutually along the width direction of the said 2nd wire. Superconducting wire.
  5. 　前記高温超電導体は、ＲＥＢＣＯであり、
    　前記接合層の結晶方位は、前記第１超電導層及び前記第２超電導層の結晶方位に沿う、請求項１～請求項４のいずれか１項に記載の超電導線。     The high temperature superconductor is REBCO;
    The superconducting wire according to any one of claims 1 to 4, wherein a crystal orientation of the bonding layer is along a crystal orientation of the first superconducting layer and the second superconducting layer.
  6. 　第１超電導層を有する第１線材と第２超電導層を有する第２線材とを準備する工程と、
    　前記第２超電導層上に接合層を形成する工程と、
    　前記第１超電導層と前記接合層とが対向した状態で、前記第１線材と前記第２線材との間に加熱しながら圧力を印加する工程と、
    　前記接合層に酸素を導入する工程とを備え、
    　前記圧力は、前記第１超電導層が前記接合層と接合される部分を含み、かつ前記第１超電導層に接合される前記接合層の周囲において前記第１線材と前記第２線材とが互いに離間するように印加される、超電導線の接合方法。     Preparing a first wire having a first superconducting layer and a second wire having a second superconducting layer;
    Forming a bonding layer on the second superconducting layer;
    Applying pressure while heating between the first wire and the second wire in a state where the first superconducting layer and the bonding layer are opposed to each other;
    A step of introducing oxygen into the bonding layer,
    The pressure includes a portion where the first superconducting layer is joined to the joining layer, and the first wire and the second wire are separated from each other around the joining layer joined to the first superconducting layer. A superconducting wire joining method applied as described above.
  7. 　前記圧力は、前記第１線材及び前記第２線材を加圧治具で挟持するとともに、前記加圧治具と前記第１線材及び前記第２線材の少なくとも一方との間に板状部材を挿入することにより印加され、
    　前記板状部材は、平面視において前記接合層に接合される前記第１超電導層と重なる位置に配置される、請求項６に記載の超電導線の接合方法。     The pressure sandwiches the first wire and the second wire with a pressure jig, and inserts a plate-like member between the pressure jig and at least one of the first wire and the second wire. Is applied by
    The superconducting wire joining method according to claim 6, wherein the plate-like member is disposed at a position overlapping the first superconducting layer joined to the joining layer in plan view.
  8. 　中心軸を有する超電導コイルであって、
    　請求項１～請求項５のいずれか１項に記載の前記超電導線を備え、
    　前記超電導線は、前記中心軸周りに巻き回される、超電導コイル。     A superconducting coil having a central axis,
    The superconducting wire according to any one of claims 1 to 5,
    The superconducting coil is a superconducting coil wound around the central axis.
  9. 　請求項８に記載の前記超電導コイルと、
    　内部に前記超電導コイルを格納するクライオスタットと、
    　前記超電導コイルを冷却する冷凍機とを備える、超電導機器。     The superconducting coil according to claim 8,
    A cryostat storing the superconducting coil therein;
    A superconducting device comprising a refrigerator for cooling the superconducting coil.
PCT/JP2017/018880 2017-05-19 2017-05-19 Superconducting wire, superconducting wire joining method, superconducting coil, and superconducting device WO2018211701A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/JP2017/018880 WO2018211701A1 (en) 2017-05-19 2017-05-19 Superconducting wire, superconducting wire joining method, superconducting coil, and superconducting device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2017/018880 WO2018211701A1 (en) 2017-05-19 2017-05-19 Superconducting wire, superconducting wire joining method, superconducting coil, and superconducting device

Publications (1)

Publication Number Publication Date
WO2018211701A1 true WO2018211701A1 (en) 2018-11-22

Family

ID=64274091

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2017/018880 WO2018211701A1 (en) 2017-05-19 2017-05-19 Superconducting wire, superconducting wire joining method, superconducting coil, and superconducting device

Country Status (1)

Country Link
WO (1) WO2018211701A1 (en)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007141688A (en) * 2005-11-18 2007-06-07 Railway Technical Res Inst Low ac loss oxide superconductor and its manufacturing method
JP2008066399A (en) * 2006-09-05 2008-03-21 Sumitomo Electric Ind Ltd Connection structure of superconducting wire rod, superconducting coil, and connecting method of superconducting wire rod
JP2014130793A (en) * 2012-11-30 2014-07-10 Fujikura Ltd Connection structure of oxide superconductive wire material and its manufacturing method
JP2014150223A (en) * 2013-02-04 2014-08-21 Sumitomo Electric Ind Ltd Superconducting coil and superconducting coil device
JP2016110816A (en) * 2014-12-05 2016-06-20 株式会社フジクラ Connection structure of superconducting wire rod and method for producing the connection structure of the superconducting wire rod
JP2016201328A (en) * 2015-04-14 2016-12-01 古河電気工業株式会社 Connection structure for superconducting wire rods and connection method for superconducting wire rods

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007141688A (en) * 2005-11-18 2007-06-07 Railway Technical Res Inst Low ac loss oxide superconductor and its manufacturing method
JP2008066399A (en) * 2006-09-05 2008-03-21 Sumitomo Electric Ind Ltd Connection structure of superconducting wire rod, superconducting coil, and connecting method of superconducting wire rod
JP2014130793A (en) * 2012-11-30 2014-07-10 Fujikura Ltd Connection structure of oxide superconductive wire material and its manufacturing method
JP2014150223A (en) * 2013-02-04 2014-08-21 Sumitomo Electric Ind Ltd Superconducting coil and superconducting coil device
JP2016110816A (en) * 2014-12-05 2016-06-20 株式会社フジクラ Connection structure of superconducting wire rod and method for producing the connection structure of the superconducting wire rod
JP2016201328A (en) * 2015-04-14 2016-12-01 古河電気工業株式会社 Connection structure for superconducting wire rods and connection method for superconducting wire rods

Similar Documents

Publication Publication Date Title
KR101374177B1 (en) Methods of splicing 2g rebco high temperature superconductors using partial micro-melting diffusion pressurized splicing by direct face-to-face contact of high temperature superconducting layers and recovering superconductivity by oxygenation annealing
JP4810268B2 (en) Superconducting wire connection method and superconducting wire
KR101427204B1 (en) METHOD OF PERSISTENT CURRENT MODE SPLICING OF 2G ReBCO HIGH TEMPERATURE SUPERCONDUCTORS USING SOLID STATE PRESSURIZED ATOMS DIFFUSION BY DIRECT FACE-TO FACE CONTACT OF HIGH TEMPERATURE SUPERCONDUCTING LAYERS AND RECOVERING SUPERCONDUCTIVITY BY OXYGENATION ANNEALING
US20080207458A1 (en) Superconductive Magnet for Persistent Current and Method for Manufacturing the Same
JP6479545B2 (en) Superconducting wire connection structure and superconducting wire connection method
US20200028061A1 (en) Connection structure
EP2056305B1 (en) Superconducting coil and superconducting conductor for use therein
CN108028106B (en) Connection structure of superconducting wire
JP5274895B2 (en) Oxide superconducting conductor
WO2018211701A1 (en) Superconducting wire, superconducting wire joining method, superconducting coil, and superconducting device
JP7032392B2 (en) Superconducting magnet
JP2009117202A (en) Superconductive tape, manufacturing method thereof, coil, and magnet
KR101535844B1 (en) METHOD OF SPLICING AND REINFORCING OF SPLICING PART FOR PERSISTENT CURRENT MODE OF 2G ReBCO HIGH TEMPERATURE SUPERCONDUCTORS
JP2012064495A (en) Method of producing coated superconducting wire rod, electrodeposition method of superconducting wire rod, and coated superconducting wire rod
KR101505851B1 (en) Method of manufacturing double pancake type persistent current mode magnet
JP6356046B2 (en) Superconducting wire connection structure, superconducting wire and connection method
JP6904875B2 (en) Connection structure of oxide superconducting wire and connection method of oxide superconducting wire
JP6707164B1 (en) Superconducting wire connection structure and superconducting wire
JP2007115635A (en) High temperature superconducting coil and its manufacturing method
WO2018211700A1 (en) Superconducting wire material, superconducting coil, superconducting magnet, and superconducting device
JP7228680B2 (en) Cable containing HTS tape and method of manufacturing same
JP7472067B2 (en) Superconducting layer connection structure, superconducting wire, superconducting coil, and superconducting device
KR102416479B1 (en) Persistent current mode splicing of second generation rebco hihg-temperature superconductor by direct contact and solid state coupling of rebco superconductiong layer
WO2020161909A1 (en) Superconducting wire connection structure
US20240079162A1 (en) High-temperature superconducting coated conductor and method for manufacturing same

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 17910280

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 17910280

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: JP