Superconductor and superconductor with electrode

Abstract

To provide a superconducting conductor capable of reducing connection resistance to an electrode, and a superconducting conductor with an electrode.SOLUTION: The superconducting conductor 20 includes a core 30 and a tape-shaped superconducting wire 10 helically wound around the core 30. The superconducting wire 10 includes at least a tape-like base material and a superconducting layer laminated on the base material. The superconducting conductor 20 is wound around the core 30 so that the superconducting layer is positioned on the outer circumferential side with respect to the base material.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a superconducting conductor and a superconducting conductor with electrodes. [Background technology]

[0002] Patent Document 1 discloses a superconducting conductor including a stranded wire and a superconducting wire wound around the stranded wire. The superconducting wire has, for example, a substrate and a superconducting layer laminated on the substrate. Electrodes may be attached to the ends of the superconducting conductor. The electrodes are electrically connected to the superconducting conductor by contacting the outer surface of the superconducting conductor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-177409 Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned superconducting conductor, the connection resistance between the conductor and the electrodes may be high in some cases, and therefore there has been a demand for lowering the connection resistance between the conductor and the electrodes.

[0005] An object of one aspect of the present invention is to provide a superconducting conductor and a superconducting conductor with electrodes that can reduce connection resistance to electrodes. [Means for solving the problem]

[0006] A superconducting conductor according to a first aspect of the present invention comprises a core and a tape-shaped superconducting wire wound spirally around the core, the superconducting wire having at least a tape-shaped substrate and a superconducting layer laminated on the substrate, and is wound around the core so that the superconducting layer is located on the outer periphery of the substrate.

[0007] According to the first aspect of the present invention, when an electrode is attached to a superconducting conductor, the superconducting layer of the superconducting wire is disposed in a position facing the surface of the electrode, thereby making it possible to reduce the connection resistance between the superconducting wire and the electrode.

[0008] A second aspect of the present invention is a superconducting conductor according to the first aspect, further comprising a metal layer formed to be thicker than the substrate, the metal layer being joined to the superconducting layer side of the superconducting wire.

[0009] A third aspect of the present invention is the superconducting conductor according to the first or second aspect, wherein a plurality of the superconducting wires are provided.

[0010] A fourth aspect of the present invention is the superconducting conductor according to any one of the first to third aspects, wherein the core has a circular cross section perpendicular to the longitudinal direction.

[0011] A fifth aspect of the present invention is the superconducting conductor according to any one of the first to fourth aspects, wherein the core has an outer diameter of 15 mm or less.

[0012] A superconducting conductor with electrodes according to a sixth aspect of the present invention comprises the superconducting conductor according to any one of the first to fifth aspects, and electrodes provided in contact with the outer surface of the superconducting wire. [Effects of the Invention]

[0013] According to one aspect of the present invention, it is possible to provide a superconducting conductor and a superconducting conductor with electrodes that can reduce the connection resistance to the electrodes. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a perspective view of a superconducting conductor according to a first embodiment. [Figure 2] FIG. 1 is a side view of a superconducting conductor according to a first embodiment. [Figure 3] 1 is a cross-sectional view of a superconducting conductor according to a first embodiment. [Figure 4]1 is a schematic diagram showing a cross section of a superconducting wire of a superconducting conductor according to a first embodiment. [Figure 5] 1 is a longitudinal cross-sectional view of a portion of a superconducting conductor with electrodes according to an embodiment. [Figure 6] 1 is a cross-sectional view of a superconducting conductor with electrodes according to an embodiment. [Figure 7] 5 is a schematic diagram showing a cross section of a superconducting wire of a superconducting conductor according to a second embodiment. FIG. [Figure 8] FIG. 10 is a side view of a superconducting conductor according to a third embodiment. [Figure 9] 1 is a graph showing current-voltage characteristics. [Figure 10] 1 is a graph showing the effect of metal layer thickness on allowable bend radius. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, a superconducting conductor and a superconducting conductor with electrodes according to an embodiment will be described with reference to the drawings.

[0016] [Superconducting conductor] (First embodiment) Fig. 1 is a perspective view of a superconducting conductor 20 according to the first embodiment. Fig. 2 is a side view of the superconducting conductor 20. Fig. 3 is a cross-sectional view of the superconducting conductor 20. Fig. 3 shows a cross section perpendicular to the longitudinal direction of the superconducting conductor 20.

[0017] As shown in FIGS. 1 to 3, a superconducting conductor 20 includes a core 30 (core material) and one or more oxide superconducting wires 10. As shown in FIG. 1, the core 30 is a wire extending in one direction (along the central axis C1). The cross section of the core 30 perpendicular to the longitudinal direction is circular. The core 30 is formed of a metal such as copper, a copper alloy, aluminum, an aluminum alloy, or stainless steel. The core 30 may be formed of a single wire or an assembly of multiple wires. The material of the core 30 is not particularly limited. The core 30 may be formed of a non-metallic material such as resin.

[0018] The outer diameter of core 30 is preferably 15 mm or less. The outer diameter of core 30 is more preferably 5 mm or less. When the outer diameter of core 30 is 15 mm or less, the bending characteristics of superconducting conductor 20 are excellent. The outer radius of core 30 is desirably equal to or greater than the allowable bending radius of oxide superconducting wire 10. For example, when substrate 1 (see FIG. 4) has a thickness of 50 μm, the outer diameter of core 30 can be 10 mm to 20 mm (e.g., 10 mm to 15 mm).

[0019] FIG. 4 is a schematic diagram showing a cross section of oxide superconducting wire 10. As shown in FIG. As shown in Fig. 4, oxide superconducting wire 10 includes superconducting laminate 5 and stabilization layer 6. Oxide superconducting wire 10 is an example of a "superconducting wire." Oxide superconducting wire 10 is formed in a tape shape.

[0020] The superconducting laminate 5 has a structure in which an oxide superconducting layer 3 and a protective layer 4 are formed on one surface of a substrate 1 via an intermediate layer 2. More specifically, the superconducting laminate 5 has a configuration in which the intermediate layer 2, the oxide superconducting layer 3, and the protective layer 4 are laminated in this order on one surface of the substrate 1.

[0021] The X direction is the width direction of the oxide superconducting wire 10. The Y direction is the length direction of the oxide superconducting wire 10 and is a direction perpendicular to the X direction. The Z direction is the thickness direction of the oxide superconducting wire 10 and is the direction in which the substrate 1, intermediate layer 2, oxide superconducting layer 3, protective layer 4, etc. are stacked. The Z direction is a direction perpendicular to the X and Y directions. The XZ cross section is a cross section defined by the X and Z directions.

[0022] The substrate 1 is tape-shaped and made of a metal such as Hastelloy (registered trademark). One surface of the substrate 1 (the surface on which the intermediate layer 2 is formed) is a first main surface 1a. The surface opposite to the first main surface 1a is a second main surface 1b.

[0023] The intermediate layer 2 includes, for example, a diffusion prevention layer, a bed layer, an orientation layer, a cap layer, etc., from the substrate 1 side. The diffusion prevention layer has the function of preventing some of the components of the substrate 1 from diffusing and becoming mixed as impurities into the oxide superconducting layer 3. The bed layer reduces reactions at the interface between the substrate 1 and the oxide superconducting layer 3, improving the orientation of the layer formed thereon. The orientation layer controls the crystal orientation of the cap layer. The cap layer is made of a material that allows crystal grains to self-orient in the in-plane direction.

[0024] The oxide superconducting layer 3 is made of an oxide superconductor. The oxide superconductor is not particularly limited, but for example, a superconductor having the general formula REBa2Cu3O X An example is an RE-Ba-Cu-O based oxide superconductor represented by (RE123). The rare earth element RE may be one or more of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. The oxide superconducting layer 3 is formed on the main surface 2a (the surface opposite to the substrate 1 side) of the intermediate layer 2. The oxide superconducting layer 3 is laminated on the first main surface 1a of the substrate 1 via the intermediate layer 2.

[0025] The protective layer 4 has functions such as bypassing overcurrent that occurs in the event of an accident and suppressing chemical reactions that occur between the oxide superconducting layer 3 and layers provided on the protective layer 4. Examples of materials for the protective layer 4 include silver (Ag), copper (Cu), gold (Au), gold-silver alloys, other silver alloys, copper alloys, and gold alloys. The protective layer 4 covers at least the main surface 3a of the oxide superconducting layer 3 (the surface opposite to the intermediate layer 2 side). The protective layer 4 is in contact with the main surface 3a of the oxide superconducting layer 3.

[0026] The substrate 1, intermediate layer 2, oxide superconducting layer 3 and protective layer 4 can be formed by known techniques.

[0027] Reference numeral 5a denotes a first main surface (main surface 4a of protective layer 4) of the oxide superconducting laminate 5. The first main surface 5a is the surface of the oxide superconducting laminate 5 on which the oxide superconducting layer 3 is formed. Reference numeral 5b denotes a side surface of the oxide superconducting laminate 5 (the side surface of the substrate 1, the side surface of the intermediate layer 2, the side surface of the oxide superconducting layer 3, and the side surface of the protective layer 4). Reference numeral 5c denotes a second main surface of the oxide superconducting laminate 5 (second main surface 1b of the substrate 1), which is the surface opposite to the first main surface 5a. The second main surface 5c is the surface of the oxide superconducting laminate 5 on which the substrate 1 is formed.

[0028] The stabilization layer 6 is provided to cover the entire outer peripheral surface of the superconducting laminate 5. That is, the stabilization layer 6 covers the first main surface 5a, the side surfaces 5b, 5b, and the second main surface 5c of the oxide superconducting laminate 5. The stabilization layer 6 is formed to surround the oxide superconducting laminate 5.

[0029] The stabilization layer 6 functions as a bypass section that diverts an overcurrent that occurs when the oxide superconducting layer 3 transitions to a normal conducting state. Examples of materials that can be used to form the stabilization layer 6 include metals such as copper, copper alloys (e.g., Cu-Zn alloys, Cu-Ni alloys, etc.), aluminum, aluminum alloys, and silver. The stabilization layer 6 can be formed by plating (e.g., electrolytic plating).

[0030] The XZ cross section of the oxide superconducting wire 10 is, for example, rectangular. Of the surfaces of the oxide superconducting wire 10 (more specifically, the surface of the stabilization layer 6), the surfaces along the X and Y directions are referred to as "main surfaces." Of the two main surfaces of the oxide superconducting wire 10, the main surface facing the substrate 1 (the bottom surface in FIG. 4) is the "first main surface 10a." Of the two main surfaces of the oxide superconducting wire 10, the surface opposite the first main surface 10a (the top surface in FIG. 4) is the "second main surface 10b." The width (dimension in the X direction) of the oxide superconducting wire 10 is greater than the thickness (dimension in the Z direction) of the oxide superconducting wire 10.

[0031] 1 and 2, the oxide superconducting wire 10 is wound spirally around the outer surface of the core 30. The oxide superconducting wire 10 is wound around the core 30 with the second main surface 10b facing outward. That is, the oxide superconducting wire 10 is wound around the core 30 with the first main surface 10a facing the core 30 (see FIG. 3). Therefore, the oxide superconducting wire 10 is wound around the core 30 so that the oxide superconducting layer 3 is located on the outer periphery of the core 30 with respect to the substrate 1 (see FIG. 4).

[0032] The oxide superconducting wire 10 may be wound spirally around the core 30 in either a single-thread or multiple-thread winding. Single-thread winding is a winding in which one oxide superconducting wire 10 is wound spirally around the core 30. Multiple-thread winding is a winding in which a plurality of oxide superconducting wires 10 are wound spirally around the core 30 in parallel.

[0033] The oxide superconducting wire 10 can be wound spirally around the core 30 in a variety of ways, including butt winding and gap winding. Butt winding is a method of winding in which the side edges of the tapes are butted together so that they do not overlap. Gap winding is a method of winding in which the tapes are wound with a gap between them. The oxide superconducting wire 10 can be wound in a single layer or multilayer manner. Multilayer winding of the superconducting conductor 20 can be used in high current applications.

[0034] In this embodiment, the superconducting conductor 20 includes a core 30 (core material) and a plurality of oxide superconducting wires 10. The number of oxide superconducting wires 10 is, for example, two. The two oxide superconducting wires 10 are a first oxide superconducting wire 10A and a second oxide superconducting wire 10B, respectively. The two oxide superconducting wires 10 (10A, 10B) are wound around the core 30 in a double winding. The number of oxide superconducting wires 10 is not particularly limited and may be any number equal to or greater than two.

[0035] The oxide superconducting wire 10 may or may not be bonded to the outer surface of the core 30. When the oxide superconducting wire 10 is bonded to the core 30, the oxide superconducting wire 10 can be bonded to the core 30 by solder, an adhesive, or the like.

[0036] [Superconductor with electrodes] Fig. 5 is a longitudinal cross-sectional view of a portion of a superconducting conductor 40 with electrodes according to an embodiment. Fig. 5 shows a cross-section along the longitudinal direction of the superconducting conductor 20. Fig. 6 is a transverse cross-sectional view of the superconducting conductor 40 with electrodes. Fig. 6 shows a cross-section perpendicular to the longitudinal direction of the superconducting conductor 20.

[0037] As shown in FIGS. 5 and 6, the superconducting conductor with electrodes 40 includes the superconducting conductor 20 and electrodes 50 . The electrode 50 is formed, for example, in a cylindrical shape having an insertion hole 51. The electrode 50 is made of a metal such as copper. The insertion hole 51 is formed along the central axis C2 of the electrode 50. The insertion hole 51 is formed so as to penetrate the electrode 50 from one end face to the other end face of the electrode 50. The cross section of the insertion hole 51 (a cross section perpendicular to the central axis C2) is, for example, circular. The inner diameter of the insertion hole 51 is slightly larger than the outer diameter of the superconducting conductor 20. The central axis C2 of the electrode 50 coincides, for example, with the central axis C1 of the superconducting conductor 20. The shape of the electrode 50 is not limited to a cylindrical shape, and may be a rectangular cylindrical shape, an elliptical cylindrical shape, or the like.

[0038] The electrode 50 is provided, for example, on at least one end of the superconducting conductor 20. The end of the superconducting conductor 20 is inserted into the insertion hole 51. The outer surface 20a of the superconducting conductor 20 is in direct or indirect contact with the inner surface 51a of the insertion hole 51. In this embodiment, a metallic bonding layer 52 is formed between the outer surface 20a of the superconducting conductor 20 and the inner surface 51a of the insertion hole 51. The outer surface 20a of the superconducting conductor 20 is in contact with the inner surface 51a of the insertion hole 51 via the metallic bonding layer 52. The metallic bonding layer 52 bonds the electrode 50 to the superconducting conductor 20. The metallic bonding layer 52 is formed of a metal such as solder or an Sn alloy. The outer surface 20a of the superconducting conductor 20 and the inner surface 51a of the insertion hole 51 may also be in direct contact.

[0039] The metal bonding layer 52 is in contact with the second main surface 10b of the oxide superconducting wire 10 of the superconducting conductor 20, thereby being electrically connected to the oxide superconducting wire 10. The metal bonding layer 52 is in contact with the inner surface 51a of the insertion hole 51, thereby being electrically connected to the electrode 50. The superconducting conductor 20 and the electrode 50 are electrically connected via the metal bonding layer 52.

[0040] [Effects of the superconducting conductor and superconducting conductor with electrodes according to the embodiment] In the superconducting conductor 20 according to this embodiment, the oxide superconducting wire 10 is wound around the core 30 such that the oxide superconducting layer 3 is located on the outer periphery of the core 30 relative to the substrate 1 (see FIGS. 1 and 4). Therefore, as shown in FIGS. 5 and 6, when an electrode 50 is attached to the superconducting conductor 20, the oxide superconducting layer 3 of the oxide superconducting wire 10 is located in a position facing the inner surface 51a of the electrode 50. This makes it possible to reduce the connection resistance between the oxide superconducting wire 10 and the electrode 50.

[0041] In the superconducting conductor 20, the connection resistance between the oxide superconducting wire 10 and the electrode 50 can be reduced, and therefore the bias (drift) of the current flowing through the two oxide superconducting wires 10 (10A, 10B) can be reduced.

[0042] The superconducting conductor 20 can have improved electrical properties because it has a plurality of oxide superconducting wires 10. Although current drift is likely to occur in a superconducting conductor having a plurality of oxide superconducting wires, the superconducting conductor 20 can suppress current drift by reducing the connection resistance between the oxide superconducting wires 10 and the electrodes 50.

[0043] The superconducting conductor 20 has a core 30 with a circular cross section, and therefore has highly isotropic bending characteristics. This allows for a high degree of freedom in the bending direction, making it possible to realize an easy-to-handle superconducting conductor 20. The superconducting conductor 20 has a core 30 with a circular cross section, and therefore can have a smaller maximum outer diameter than when a core with a non-circular cross section is used.

[0044] [Superconducting conductor] (Second embodiment) FIG. 7 is a schematic diagram showing a cross section of an oxide superconducting wire 110 of a superconducting conductor according to the second embodiment. 7, the superconducting conductor according to this embodiment includes an oxide superconducting wire 110 instead of the oxide superconducting wire 10 (see FIG. 4). Components common to the first embodiment are denoted by the same reference numerals and will not be described.

[0045] The oxide superconducting wire 110 includes a wire body 10A having the same configuration as the oxide superconducting wire 10 (see FIG. 4), and a metal layer 60. The oxide superconducting wire 110 differs from the oxide superconducting wire 10 (see FIG. 4) in that it includes the metal layer 60.

[0046] The metal layer 60 is overlaid on and bonded to the second main surface 10b of the wire body 10A. That is, the metal layer 60 is provided on the oxide superconducting layer 3 side of the wire body 10A (the upper surface side in FIG. 7 ). The metal layer 60 is made of a metal such as copper or a copper alloy. The metal layer 60 is formed in a tape shape. The metal layer 60 is formed along the longitudinal direction of the wire body 10A. The metal layer 60 is in direct or indirect contact with the second main surface 10b of the wire body 10A. The metal layer 60 may be bonded to the second main surface 10b of the wire body 10A via, for example, a metal bonding layer. The metal bonding layer is made of, for example, a metal such as solder or an Sn alloy.

[0047] Metal layer 60 is formed to be thicker than substrate 1. That is, thickness T2 (dimension in the Z direction) of metal layer 60 is greater than thickness T1 of substrate 1. Thickness T2 of metal layer 60 can be set to be, for example, 1.2 times or more and 3 times or less the thickness T1 of substrate 1. By setting thickness T2 of metal layer 60 within this range, strain (tensile strain) when oxide superconducting wire 110 is bent can be reduced, and ease of bending of oxide superconducting wire 110 can be ensured.

[0048] The width (dimension in the X direction) of the metal layer 60 is, for example, smaller than the width of the wire body 10A. The width (dimension in the X direction) of the metal layer 60 may be the same as or larger than the width of the wire body 10A.

[0049] [Effects of the superconducting conductor according to the embodiment] In the superconducting conductor according to this embodiment, similarly to the superconducting conductor 20 according to the first embodiment, it is possible to reduce the connection resistance between the oxide superconducting wire 110 and the electrode 50. It is also possible to reduce the bias (drift) of the current flowing through the plurality of oxide superconducting wires 110.

[0050] The superconducting conductor according to this embodiment uses an oxide superconducting wire 110 having a metal layer 60 on the oxide superconducting layer 3 side of the wire body 10A (the upper surface side in FIG. 7), and therefore when the oxide superconducting wire 110 is bent with the oxide superconducting layer 3 on the outer periphery, it is possible to reduce strain (tensile strain) generated in the oxide superconducting layer 3. This makes it possible to reduce the allowable bending radius of the superconducting conductor.

[0051] [Superconducting conductor] (Third embodiment) 8 is a side view of a superconducting conductor 220 according to the third embodiment. The same reference numerals are used to designate the same components as those in the other embodiments, and the description thereof will be omitted. 8, the superconducting conductor 220 includes a core 30 and one oxide superconducting wire 10. The oxide superconducting wire 10 is wound around the core 30 such that the oxide superconducting layer 3 is located on the outer periphery of the core 30 relative to the substrate 1 (see FIG. 4).

[0052] In the superconducting conductor 220 according to this embodiment, similarly to the superconducting conductor 20 according to the first embodiment, it is possible to reduce the connection resistance between the oxide superconducting wire 110 and the electrode 50. It is also possible to reduce the bias (drift) of the current flowing through the plurality of oxide superconducting wires 110.

[0053] The present invention is not limited to the above-described embodiments, and various modifications are possible without departing from the spirit of the present invention. For example, the structure of the oxide superconducting laminate is not limited to the structure shown in Fig. 4. The oxide superconducting laminate may include layers other than the metal substrate, intermediate layer, oxide superconducting layer, and protective layer.

[0054] 5 and 6, the electrodes 50 are joined to the superconducting conductor 20 by metal joining layers 52, but the structure for attaching the electrodes to the superconducting conductor is not particularly limited. The electrodes may be attached to the superconducting conductor by crimping. The electrode 50 and the insertion hole 51 are circular when viewed in a direction parallel to the central axis C2, but the shapes of the electrode and the insertion hole are not particularly limited. For example, the shapes of the electrode and the insertion hole may be rectangular when viewed in a direction parallel to the central axis.

[0055] The cross-sectional shape of the core 30 may be, for example, elliptical, but a circular cross-sectional shape is preferable because it increases the degree of freedom in the bending direction and also allows the diameter of the superconducting conductor 20 to be made thinner. [Example]

[0056] Example 1 The superconducting conductor 20 shown in FIG. 1 was fabricated as follows. A copper core 30 was prepared. The cross section of the core 30 perpendicular to the longitudinal direction was circular. The outer diameter of the core 30 was 15 mm. An intermediate layer 2, an oxide superconducting layer 3, and a protective layer 4 were formed on a first main surface 1a of a substrate 1 (thickness: 50 μm), thereby obtaining a superconducting laminate 5. A stabilizing layer 6 (thickness: 20 μm) was formed on the outer periphery of the superconducting laminate 5. This resulted in an oxide superconducting wire 10 (width: 4 mm). The critical current (Ic) of the oxide superconducting wire 10 was approximately 150 A.

[0057] Two oxide superconducting wires 10 (10A, 10B) were wound around the core 30 by double winding. The oxide superconducting wires 10 were wound around the core 30 so that the oxide superconducting layer 3 was located on the outer periphery of the core 30 with respect to the substrate 1. In this way, a superconducting conductor 20 was obtained.

[0058] As shown in Fig. 5, a copper electrode 50 was provided at one end of the superconducting conductor 20. This resulted in a superconducting conductor 40 with electrodes. The superconducting conductor 40 with electrodes was cooled with liquid nitrogen, and the current-voltage characteristics were investigated when a current was passed from the electrode 50 to the superconducting conductor 20. The results are shown in Fig. 9.

[0059] (Comparative Example 1) A superconducting conductor was fabricated in the same manner as in Example 1, except that oxide superconducting wire 10 was wound around core 30 in the opposite orientation to that in Example 1 (the orientation in which oxide superconducting layer 3 was located on the inner periphery of core 30 relative to substrate 1). The current-voltage characteristics of this superconducting conductor were investigated in the same manner as in Example 1. The results are shown in FIG.

[0060] 9, in Comparative Example 1, the voltage increased significantly when the current exceeded 200 A. This voltage increase may be related to the bias (uneven current) of the current flowing through the two oxide superconducting wires 10. In contrast, in Example 1, no voltage increase was observed until the current approached 300 A.

[0061] Example 2 An oxide superconducting wire 110 shown in FIG. 7 was fabricated. A plurality of superconducting conductors were fabricated using a plurality of oxide superconducting wires 110 with different thicknesses of the metal layer 60. A superconducting conductor was also fabricated using an oxide superconducting wire 10 without the metal layer 60. The effect of the thickness of the metal layer 60 on the allowable bending radius of these superconducting conductors was investigated. The allowable bending radius is the bending radius at which the critical current (Ic) characteristics decrease when the oxide superconducting wire 110 is bent so that the oxide superconducting layer 3 is located on the outer periphery of the core 30. Specifically, the allowable bending radius is the bending radius of the oxide superconducting wire 110 at which the critical current decreases by 5% when compared to before bending the oxide superconducting wire 110.

[0062] The results are shown in Fig. 10. For the superconducting conductor using oxide superconducting wire 10 without metal layer 60, Fig. 10 shows the results when the thickness of the metal layer is 0.

[0063] As shown in FIG. 10, the superconducting conductor provided with the metal layer 60 was able to have a smaller allowable bending radius than the superconducting conductor without the metal layer 60. [Explanation of symbols]

[0064] 1...substrate, 3...oxide superconducting layer (superconducting layer), 10, 110...oxide superconducting wire (superconducting wire), 20, 220...superconducting conductor, 30...core, 40...superconducting conductor with electrode, 50...electrode, 60...metal layer, T1...thickness of substrate, T2...thickness of metal layer

Claims

1. a core and a tape-shaped superconducting wire wound spirally around the core, The superconducting wire has at least a tape-shaped substrate and a superconducting layer laminated on the substrate, and is wound around the core so that the superconducting layer is located on the outer circumferential side of the substrate. Superconducting conductor.

2. Further provided is a metal layer formed thicker than the base material, the metal layer is joined to the superconducting layer side of the superconducting wire; The superconducting conductor according to claim 1.

3. The superconducting wire is provided in plurality. The superconducting conductor according to claim 1.

4. The core has a circular cross section perpendicular to the longitudinal direction. The superconducting conductor according to claim 1.

5. The outer diameter of the core is 15 mm or less. The superconducting conductor according to claim 1.

6. A superconducting conductor according to any one of claims 1 to 5; an electrode provided in contact with an outer surface of the superconducting wire; Superconductor with electrodes.

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