JP2021086740A - Superconducting conductor wire, superconducting device and method for manufacturing superconducting conductor wire - Google Patents

Abstract

To provide: a superconducting conductor wire wound around a core material so that the superconducting wire rod is not separated from a surface of the core material; a superconducting device; and a method for manufacturing the superconducting conductor wire.SOLUTION: A superconducting conductor wire 20 includes a core material 30 extended in one direction, and a tape-shaped superconducting wire rod 10 spirally wound around the core material 30. An outer surface of the core material 30 includes a first circumferential direction region and a second circumferential direction region having a larger average curvature than the first circumferential direction region as viewed from a length direction of the core material 30. The superconducting wire rod 10 includes a superconducting laminate including at least a tape-shaped base material and a superconducting layer laminated on the base material. A groove part 7 located along the length direction of the core material 30 is formed on a surface of the superconducting wire rod. The groove part 7 is formed at a position where at least a part thereof is overlapped with the second circumferential direction region of the core material 30 as viewed from a thickness direction of the superconducting wire rod 10.SELECTED DRAWING: Figure 1

Description

The present invention relates to superconducting conductor wires, superconducting equipment, and methods for manufacturing superconducting conductor wires.

Non-Patent Document 1 discloses a superconducting conductor wire. This superconducting conductor wire is configured by spirally winding a superconducting wire material (see, for example, Patent Document 1) around the outer peripheral surface of the core material. Superconducting conductor wires are used in superconducting equipment such as superconducting magnets. For example, a superconducting magnet is formed by assembling the superconducting conductor wires.

“YBa2Cu3O7-δ coated conductor cabling for low ac-loss and high-field magnet applications.” Supercond. Sci. Technol. 22 (2009) 065013 (5pp)

JP-A-2018-195612

In order to increase the density of the superconducting wire in the superconducting device, a superconducting conductor wire using a core material having a non-circular cross section (for example, a flat shape) is advantageous.
However, when a core material having a non-circular cross section is used for the superconducting conductor wire, the superconducting wire material may be in a form separated from the surface of the core material on a part of the surface of the core material.

One aspect of the present invention is a method for manufacturing a superconducting conductor wire, a superconducting device, and a superconducting conductor wire wound around the core material so that the superconducting wire does not separate from the surface of the core material even when the core material has a non-circular cross section. The challenge is to provide.

One aspect of the present invention includes a core material extending in one direction and a tape-shaped superconducting wire material spirally wound around the core material, and the outer surface of the core material is a region in the first circumferential direction. And a second circumferential region having a larger average curvature than the first circumferential region when viewed from the length direction of the core material, and the superconducting wire is laminated on at least a tape-shaped base material and the base material. A superconducting laminate having the superconducting layer is provided, and a groove portion along the length direction of the core material is formed on the surface of the superconducting wire material, and the groove portion is at least seen from the thickness direction of the superconducting wire material. Provided is a superconducting conductor wire, which is partially formed at a position overlapping the second circumferential direction region of the core material.

Since a groove is formed in the superconducting conductor wire, the superconducting wire material is easily bent at the portion where the groove is formed. Therefore, the superconducting wire easily has a bent shape along the core material. When the core material 30 has a non-circular cross section, the superconducting conductor wire is wound so that the superconducting wire material does not separate from the core material even in a place where the average curvature of the outer surface of the core material is large (region in the second circumferential direction). It becomes the form. At the location where the groove is formed, the bending strain generated in the superconducting wire is small. Therefore, deterioration of superconducting characteristics can be suppressed.

The superconducting wire material is wound around the core material so that the base material is located on the outer peripheral side with respect to the superconducting layer, and the groove portion is formed on the surface of the superconducting wire material on the base material side. preferable.

It is preferable that the superconducting wire further includes a stabilizing layer that covers the superconducting laminate, and the groove is formed on the surface of the stabilizing layer so as to reach the base material.

The depth D of the groove preferably satisfies t / 10 ≦ D ≦ 2t / 3, where t is the thickness of the superconducting wire.

In the cross section orthogonal to the length direction of the groove, the shape of the groove is preferably U-shaped.

One aspect of the present invention provides a superconducting device configured by assembling the superconducting conductor wires.

Another aspect of the present invention is a tape-shaped superconducting wire having a core material extending in one direction and a superconducting laminate having at least a tape-shaped base material and a superconducting layer laminated on the base material. A first step of spirally winding the superconducting wire around the core material and a second step of forming a groove along the axial direction of the core material are provided, and the outer surface of the core material is: It has a first circumferential region and a second circumferential region having a larger average curvature than the first circumferential region when viewed from the length direction of the core material. In the second step, the groove portion is superconducting. Provided is a method for manufacturing a superconducting conductor wire, which is formed at a position where at least a part of the wire rod overlaps the second circumferential direction region of the core material when viewed from the thickness direction of the wire rod.

According to the manufacturing method, a groove is formed after the oxide superconducting wire is wound around the core material. Therefore, in the superconducting conductor wire, the position of the groove portion with respect to the core material can be accurately determined.

Yet another aspect of the present invention includes a first step of forming a groove in a tape-shaped superconducting wire having a superconducting laminate having at least a tape-shaped base material and a superconducting layer laminated on the base material. The second step of spirally winding the superconducting wire around the core material extending in one direction, and the outer surface of the core material is the first circumferential direction region and the above-mentioned when viewed from the length direction of the core material. It has a second circumferential region having a larger average curvature than the first circumferential region, and in the second step, the groove is along the length direction of the core material and viewed from the thickness direction of the superconducting wire. Further, the present invention provides a method for manufacturing a superconducting conductor wire, which is arranged at a position where at least a part of the core material overlaps the second circumferential direction region.

In the above-mentioned manufacturing method, since a groove is formed in the oxide superconducting wire prior to winding the oxide superconducting wire around the core material, the groove forming work is easy.

According to one aspect of the present invention, even when the core material has a non-circular cross section, the superconducting conductor wire, the superconducting device, and the superconducting conductor wire wound around the core material so that the superconducting wire does not separate from the surface of the core material are manufactured. A method can be provided.

It is a perspective view of the superconducting conductor wire of 1st Embodiment. It is an enlarged perspective view of the superconducting conductor wire of 1st Embodiment. It is a perspective view of the core material of the superconducting conductor wire of 1st Embodiment. It is a perspective view which looked at the oxide superconducting wire from one side. It is a perspective view which looked at the oxide superconducting wire from the other side. It is a top view of the oxide superconducting wire. It is sectional drawing of a part of the oxide superconducting wire, and is the schematic diagram of the groove part. It is a figure explaining the manufacturing method of the superconducting conductor wire of 1st Embodiment, and is explanatory drawing of the process of winding a superconducting wire material around a core material. It is the figure which looked at the wound conductor wire around which the superconducting wire material was wound from the length direction. It is a top view of the groove forming apparatus. It is the figure which looked at the groove forming apparatus of the previous figure from the length direction of the winding conductor wire. It is a block diagram of a press apparatus. It is a figure which shows the operation of the press device of the previous figure. It is a perspective view of the superconducting conductor wire of 2nd Embodiment. It is an enlarged perspective view of the superconducting conductor wire of 2nd Embodiment. It is a perspective view of the core material of the superconducting conductor wire of 2nd Embodiment. It is a top view of the oxide superconducting wire. It is a perspective view of another example of a core material. It is a schematic diagram of the 1st modification of the groove part. It is a schematic diagram of the 2nd modification of the groove part. It is a schematic diagram of the 3rd modification of the groove part. It is a perspective view of the superconducting magnet which is an example of a superconducting device.

Hereinafter, the present invention will be described with reference to the drawings based on the preferred embodiments.

[Superconducting Conductor Wire] (First Embodiment)
FIG. 1 is a perspective view showing the superconducting conductor wire 20 of the first embodiment. FIG. 2 is an enlarged perspective view of the superconducting conductor wire 20. FIG. 3 is a perspective view of the core material 30.

As shown in FIGS. 1 and 2, the superconducting conductor wire 20 includes a core material 30 and an oxide superconducting wire material 10.
As shown in FIG. 3, the core material 30 has a tubular shape extending in the A1 direction (one direction). "A1" is the central axis of the core material 30, and "A1 direction" is the length direction of the core material 30. The core material 30 has a non-circular shape (specifically, an elliptical shape) when viewed from the A1 direction. That is, the cross section of the core material 30 orthogonal to the A1 direction is a non-circular shape (specifically, an elliptical shape). The core material 30 is made of a metal such as copper or stainless steel.

The outer surface 30a of the core material 30 can be partitioned into a plurality of strip-shaped circumferential regions 30b, 30c, 30b, 30c extending in the A1 direction. Specifically, the outer surface 30a has a pair of first circumferential regions 30b and 30b and a pair of second circumferential regions 30c and 30c. The first circumferential region 30b, the second circumferential region 30c, the first circumferential region 30b, and the second circumferential region 30c are arranged side by side in this order in the circumferential direction of the core member 30.

The first circumferential direction regions 30b and 30b are substantially arcuate when viewed from the A1 direction. The pair of first circumferential regions 30b, 30b are located at positions that are rotationally symmetric with respect to the central axis of the core member 30. The two first circumferential regions 30b and 30b are separated by the second circumferential regions 30c and 30c. The first circumferential region 30b is adjacent to the second circumferential region 30c. The second circumferential direction regions 30c and 30c are substantially arcuate when viewed from the A1 direction. The pair of second circumferential regions 30c and 30c are located at positions that are rotationally symmetric with respect to the central axis of the core member 30. The circumferential length of the first circumferential region 30b may be 1 to 10 times the circumferential length of the second circumferential region 30c.

When viewed from the A1 direction, the mean curvature of the second circumferential region 30c is larger than the mean curvature of the first circumferential region 30b. In other words, when viewed from the A1 direction, the mean radius of curvature of the second circumferential region 30c is smaller than the mean radius of curvature of the first circumferential region 30b.

The minor axis direction of the core material 30 is referred to as the first direction D1. The first direction D1 is a direction orthogonal to the A1 direction. The outer diameter (first outer diameter L1) of the core material 30 in the first direction D1 is the minimum diameter. The major axis direction of the core material 30 is referred to as the second direction D2. The second direction D2 is a direction orthogonal to the first directions D1 and A1. The outer diameter (second outer diameter L2) of the core material 30 in the second direction D2 is the maximum diameter. The second outer diameter L2 is larger than the first outer diameter L1. The first direction D1 is the thickness direction of the core material 30. The second direction D2 is the width direction of the core material 30. The "outer diameter" is the external dimension.
The second outer diameter L2 of the core material 30 is, for example, 2 to 10 mm. The second outer diameter L2 is, for example, 1.5 to 10 times the first outer diameter L1.

When viewed from the A1 direction, the two vertices P1 and P1 on the minor axis of the core material 30 are included in the first circumferential direction regions 30b and 30b, respectively. The vertices P1 and P1 are located, for example, in the center of the first circumferential direction regions 30b and 30b in the circumferential direction when viewed from the A1 direction. The vertices P1 and P1 are located at one end and the other end of the core material 30 in the thickness direction (first direction D1), respectively. The vertices P1 and P1 are, for example, points having the smallest curvature.

The two vertices P2 and P2 on the long axis of the core material 30 are included in the second circumferential direction regions 30c and 30c, respectively. The vertices P2 and P2 are located, for example, in the center of the second circumferential direction regions 30c and 30c in the circumferential direction when viewed from the A1 direction. The vertices P2 and P2 are located at one end and the other end of the core material 30 in the width direction (second direction D2), respectively. The vertices P2 and P2 are, for example, points having the largest curvature.

[Oxide superconducting wire]
FIG. 4 is a perspective view of the oxide superconducting wire 10 as viewed from one side. FIG. 5 is a perspective view of the oxide superconducting wire 10 as viewed from the other side. FIG. 6 is a plan view of the oxide superconducting wire 10.

As shown in FIGS. 4 and 5, the oxide superconducting wire 10 includes a superconducting laminate 5 and a stabilizing layer 6. The oxide superconducting wire 10 is a specific example of the “superconducting wire”. The oxide superconducting wire 10 is formed in a tape shape.

As shown in FIG. 5, the superconducting laminate 5 has a structure in which the oxide superconducting layer 3 and the protective layer 4 are formed on the base material 1 via the intermediate layer 2. Specifically, the superconducting laminate 5 has a structure 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 tape-shaped base material 1.

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 orthogonal to the X direction. The Z direction is the thickness direction of the oxide superconducting wire 10, and is the direction in which the base material 1, the intermediate layer 2, the oxide superconducting layer 3, the protective layer 4, and the like are laminated. The Z direction is a direction orthogonal to the X direction and the Y direction. The XZ cross section is a cross section defined by the X direction and the Z direction.

The base material 1 is in the form of a tape and is made of a metal such as Hastelloy (registered trademark).
The intermediate layer 2 includes, for example, a diffusion prevention layer, a bed layer, an alignment layer, a cap layer, and the like from the base material 1 side. The diffusion prevention layer has a function of suppressing a part of the components of the base material 1 from diffusing and being mixed as impurities on the oxide superconducting layer 3 side. The bed layer reduces the reaction at the interface between the base material 1 and the oxide superconducting layer 3 and improves the orientation of the layer formed on the bed layer. The alignment layer controls the crystal orientation of the cap layer. The cap layer is made of a material in which the crystal grains can be self-oriented in the in-plane direction.

The oxide superconducting layer 3 is composed of an oxide superconductor. As an oxide superconductor, particularly, but not limited to, for example, the general formula _{REBa 2 Cu 3 O X (RE123} ) with REBa-Cu-O based oxide superconductor represented the like. Examples of the rare earth element RE include one or more of Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu.

The protective layer 4 has functions such as bypassing an overcurrent generated at the time of an accident and suppressing a chemical reaction occurring between the oxide superconducting layer 3 and the layer provided on the protective layer 4. Examples of the material of the protective layer 4 include silver (Ag), copper (Cu), gold (Au), an alloy of gold and silver, other silver alloys, copper alloys, and gold alloys.

Known techniques can be applied to the base material 1, the intermediate layer 2, the oxide superconducting layer 3 and the protective layer 4.

The stabilizing layer 6 is provided so as to cover the entire outer peripheral surface 5a of the superconducting laminated body 5. The stabilizing layer 6 has a function as a bypass portion for commutating the overcurrent generated when the oxide superconducting layer 3 is transferred to the normal conducting state. Examples of the constituent material of the stabilizing layer 6 include metals such as copper, copper alloys (for example, Cu-Zn alloys, Cu-Ni alloys, etc.), aluminum, aluminum alloys, and silver. The stabilizing layer 6 can be formed by plating (for example, electrolytic plating).
An insulating layer may be formed on the surface of the stabilizing layer 6. For example, an insulating layer can be formed by forming a groove portion 7 described later in the oxide superconducting wire 10 and then winding a polyimide tape around the oxide superconducting wire 10.

The XZ cross section of the oxide superconducting wire 10 is, for example, rectangular. Of the surfaces of the oxide superconducting wire 10 (specifically, the surface of the stabilizing 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 (lower surface in FIG. 5) on the base material 1 side is referred to as "first main surface 10a". Of the two main surfaces of the oxide superconducting wire 10, the surface opposite to the first main surface 10a (upper surface in FIG. 5) is referred to as "second main surface 10b".
The width of the oxide superconducting wire 10 (dimension in the X direction) is larger than the thickness of the oxide superconducting wire 10 (dimension in the Z direction).

A plurality of groove portions 7 are formed on the first main surface 10a of the oxide superconducting wire 10. The groove portion 7 is linear when viewed from the thickness direction (Z direction) of the oxide superconducting wire 10 (see FIG. 6). The groove portion 7 is inclined with respect to the X direction when viewed from the Z direction. The groove portion 7 is a second end portion in the width direction (X direction) of the first main surface 10a from the first side edge 10a1 which is one end portion in the width direction (X direction) of the first main surface 10a. It is formed over the two side edges 10a2. One end of the groove 7 (the end reaching the first side edge 10a1) is referred to as the first end 7a. The other end of the groove 7 (the end reaching the second side edge 10a2) is referred to as the second end 7b. The plurality of groove portions 7 are formed at intervals in the length direction of the oxide superconducting wire member 10.

In the oxide superconducting wire 10, the groove 7 is formed on the main surface (first main surface 10a) on the base material 1 side of the two main surfaces 10a and 10b of the oxide superconducting wire 10. Therefore, at the location where the groove portion 7 is formed, the oxide superconducting layer 3 is close to the central position in the thickness direction of the oxide superconducting wire 10. Therefore, in the portion where the groove portion 7 is formed, the strain due to bending is less likely to reach the oxide superconducting layer 3. Therefore, it is possible to prevent the superconducting characteristics of the oxide superconducting wire 10 from deteriorating due to bending.

FIG. 7 is a cross-sectional view of a part of the oxide superconducting wire 10, and is a schematic view of the groove portion 7.
As shown in FIG. 7, the shape of the groove portion 7 is, for example, U-shaped in the cross section orthogonal to the length direction of the groove portion 7. When the groove portion 7 has a U-shaped cross section, bending stress is unlikely to be concentrated at a specific portion, so that deterioration of the oxide superconducting layer 3 can be suppressed.
It is desirable that the groove portion 7 penetrates the stabilizing layer 6 in the thickness direction and reaches the base material 1. When the groove portion 7 has a depth reaching the base material 1, the oxide superconducting wire 10 can be easily bent.

The depth D (mm) of the groove portion 7 preferably satisfies t / 10 ≦ D ≦ 2 t / 3. “T” is the thickness (mm) of the oxide superconducting wire 10. When the depth D is t / 10 or more, the oxide superconducting wire 10 can be easily bent. When the depth D is 2t / 3 or less, the strength of the oxide superconducting wire 10 can be ensured.
The width W of the groove portion 7 preferably satisfies 0.1 mm ≦ W ≦ 1 mm.

As shown in FIGS. 1 and 2, the oxide superconducting wire 10 is spirally wound around the outer surface 30a of the core 30. The oxide superconducting wire 10 is wound around the core 30 so that the base material 1 is located on the outer peripheral side of the core 30 with respect to the oxide superconducting layer 3.

Butt winding is preferable as a form in which the oxide superconducting wire 10 is spirally wound around the core material 30. Butt winding is a winding method in which the side edges are butted against each other so that the tapes do not overlap each other. The form in which the oxide superconducting wire 10 is spirally wound around the core 30 may be a single-row winding or a multi-row winding. The single-row winding is a form in which one oxide superconducting wire 10 is spirally wound around the core 30. The multi-row winding is a form in which a plurality of oxide superconducting wire members 10 are spirally wound around a core material 30 in parallel. The number of oxide superconducting wires 10 when multi-row winding is adopted is, for example, 1 to 3. The winding form of the oxide superconducting wire 10 may be single-layer winding or multi-layer winding. Further, a plurality of oxide superconducting wire members 10 may be stacked and wound around the core material 30.
Further, for example, a polyimide tape may be wound around the outer surface of the oxide superconducting wire 10 wound around the core material 30 to form an insulating layer.

The groove portion 7 is formed at a position where at least a part thereof overlaps the second circumferential direction regions 30c and 30c (see FIG. 3) when viewed from the thickness direction of the oxide superconducting wire 10. The groove portion 7 is formed along the A1 direction of the core material 30.

The oxide superconducting wire 10 may or may not be adhered to the outer surface 30a of the core material 30. When the oxide superconducting wire 10 is adhered to the core material 30, the oxide superconducting wire 10 can be adhered to the core 30 by solder, an adhesive or the like.

[Manufacturing method of superconducting conductor wire] (1st embodiment)
Hereinafter, an example of a method for manufacturing the superconducting conductor wire 20 will be described with reference to FIGS. 8 to 13.

(First step: Winding of oxide superconducting wire)
FIG. 8 is a diagram illustrating a method of manufacturing the superconducting conductor wire 20 of the first embodiment. FIG. 8 is an explanatory diagram of a process of winding the oxide superconducting wire 10 around the core 130. FIG. 9 is a view of the wound conductor wire 120 around which the oxide superconducting wire 10 is wound as viewed from the length direction.

As shown in FIGS. 8 and 9, the oxide superconducting wire 110 and the core 130 having the same configuration as the oxide superconducting wire 10 shown in FIGS. 4 and 5 are prepared except that the groove 7 is not provided. The core material 130 is, for example, cylindrical. The "A2 direction" is a direction along the central axis of the core material 130, and is a length direction of the core material 130.

The oxide superconducting wire 110 is wound around the surface of the core 130. The oxide superconducting wire 110 is wound around the core 130 so that the base material 1 is located on the outer peripheral side of the core 130 with respect to the oxide superconducting layer 3.
Butt winding is preferable as a form in which the oxide superconducting wire 110 is spirally wound around the core 130. The winding form of the oxide superconducting wire 110 may be a single-row winding or a multi-row winding. As the winding form of the oxide superconducting wire 110 shown in FIG. 8, a double winding, that is, a form in which two oxide superconducting wires 110 (110A, 110B) are spirally wound around the core 130 in parallel is adopted. There is. The core material 130 around which the oxide superconducting wire 110 is wound is referred to as a "wound conductor wire 120".

A solder layer may be formed on one surface of the oxide superconducting wire 110 (the surface facing the core 130) or the outer surface of the core 130. As a result, when the grooved conductor wire 121 is non-circularly deformed by using the press device 150 shown in FIG. 12, the oxide superconducting wire 110 can be soldered to the core 130 by hot pressing.

(Second step: formation of groove)
FIG. 10 is a plan view of the groove forming device 140. FIG. 11 is a view of the groove forming device 140 viewed from the length direction of the wound conductor wire 120.
As shown in FIG. 10, the groove forming device 140 includes a pair of disk-shaped blade portions 141 and 141. The blade portions 141 and 141 are installed at intervals. The wound conductor wire 120 is taken up in the length direction and passed between the blade portions 141 and 141.

As shown in FIG. 11, the blade portions 141 and 141 form a pair of groove portions 7 and 7 in the oxide superconducting wire 110. The groove portion 7 is formed along the A2 direction of the core material 130. The two groove portions 7 and 7 are formed at positions that are rotationally symmetrical around the axis of the core material 130 (positions that are displaced by 180 degrees in the circumferential direction). The wound conductor wire 120 in which the grooves 7 and 7 are formed is referred to as "grooved conductor wire 121".

(Third step: Non-circular grooved conductor wire)
FIG. 12 is a block diagram of the press device 150. FIG. 13 is a diagram showing the operation of the press device 150.
As shown in FIG. 12, the press device 150 includes a pair of plate-shaped pressing bodies 151 and 151. The pressing body 151 is, for example, a rolling roller. The rolling roller may be a flat roll, a grooved roll, a crown roll or the like.

The grooved conductor wire 121 is arranged between the pressing bodies 151 and 151, and the pressing bodies 151 and 151 are moved in a direction approaching each other. As a result, the grooved conductor wires 121 are pressed in the compression direction by using the pressing bodies 151 and 151. At this time, the position where the grooved conductor wires 121 are pressed by the pressing bodies 151 and 151 is, for example, a position deviated by 90 ° in the axial direction from the groove portion 7 when viewed from the A2 direction of the core material 130.

As shown in FIG. 13, the grooved conductor wire 121 (see FIG. 12) is compressively deformed. The cylindrical core material 130 is an elliptical tubular core material 30 (that is, a non-circular cross section) (see FIG. 1). The groove portion 7 is located at a position where at least a part thereof overlaps the second circumferential direction regions 30c and 30c (see FIG. 3) when viewed from the thickness direction of the oxide superconducting wire 10. As a result, the superconducting conductor wire 20 shown in FIG. 1 is obtained.

When an insulating layer is provided on the surface of the superconducting conductor wire 20, an insulating layer is formed after forming the groove portion 7 in the second step (formation of the groove portion), and then a third step (non-grooved conductor wire). (Circularization) may be performed. Alternatively, the insulating layer may not be formed after the second step (formation of the groove portion), and the insulating layer may be formed after the third step (non-circularization of the grooved conductor wire).

[Effects of superconducting conductor wires]
Since the groove portion 7 is formed in the superconducting conductor wire 20, the oxide superconducting wire member 10 is easily bent at the portion where the groove portion 7 is formed. Therefore, the oxide superconducting wire 10 easily has a bent shape along the second circumferential direction region 30c of the core material 30.
When the core material 30 has a non-circular cross section (specifically, an elliptical shape), the superconducting conductor wire 20 is oxidized even at a portion where the average curvature of the outer surface 30a of the core material 30 is large (second circumferential direction region 30c). The superconducting wire 10 is wound so as not to separate from the core 30.
At the location where the groove 7 is formed, the bending strain generated in the oxide superconducting wire 10 becomes small. Therefore, deterioration of superconducting characteristics can be suppressed.

In the superconducting conductor wire 20, since the oxide superconducting wire 10 is wound so as not to be separated from the core material 30, it is possible to suppress the oxide superconducting wire 10 from floating when an electromagnetic force, a thermal stress, or the like is applied. Therefore, deterioration of the oxide superconducting wire 10 due to floating (wire motion) can be suppressed.

In the superconducting conductor wire 20, it is not necessary to change the dimensions (for example, the thickness dimension) of the oxide superconducting wire material 10, so that the dimensional accuracy of the oxide superconducting wire material 10 can be improved.

Since the superconducting conductor wire 20 has a flat shape, that is, a shape in which the second outer diameter L2 of the core material 30 is larger than the first outer diameter L1, it is an oxide in a superconducting device such as a superconducting magnet (see FIG. 22). The density of the superconducting wire 10 can be increased.

[Effects of the superconducting conductor wire manufacturing method]
In the manufacturing method, the groove portion 7 is formed after the oxide superconducting wire 110 is wound around the core 130. Therefore, in the superconducting conductor wire 20, the position of the groove portion 7 with respect to the core material 30 can be accurately determined.

[Superconducting conductor wire] (second embodiment)
FIG. 14 is a perspective view showing the superconducting conductor wire 220 of the second embodiment. FIG. 15 is an enlarged perspective view of the superconducting conductor wire 220. FIG. 16 is a perspective view of the core material 230. Hereinafter, the above-mentioned configurations will be designated by the same reference numerals and description thereof will be omitted.

As shown in FIGS. 14 and 15, the superconducting conductor wire 220 includes a core material 230 and an oxide superconducting wire material 210.
As shown in FIG. 16, the core material 230 has a tape shape extending in the A3 direction (one direction). The "A3 direction" is the length direction of the core material 230. The core material 230 has a non-circular shape when viewed from the A3 direction. Specifically, the core material 230 has a rectangular shape (specifically, a rectangular shape) when viewed from the A3 direction. That is, the cross section of the core material 230 orthogonal to the A3 direction is non-circular (specifically, rectangular). The core material 230 is a metal tape made of a metal such as copper or stainless steel.
The width of the core material 230 is, for example, 5 to 10 mm. The thickness of the core material 230 is, for example, 0.1 to 2 mm.

The short side direction of the core material 230 when viewed from the A3 direction is referred to as the first direction D3. The first direction D3 is a direction orthogonal to the A3 direction. The external dimension of the core material 230 in the first direction D3 (first external dimension L3) is the minimum external dimension. The long side direction of the core material 230 is referred to as the second direction D4. The second direction D4 is a direction orthogonal to the first directions D3 and A3. The external dimension (second external dimension L4) of the core material 230 in the second direction D4 is the maximum external dimension. The second external dimension L4 is larger than the first external dimension L3. The first direction D3 is the thickness direction of the core material 230. The second direction D4 is the width direction of the core material 230.

Of the outer surface 230a of the core material 230, the surfaces along the A3 direction and the second direction D4 are referred to as main surfaces 230e and 230e. The surfaces along the A3 direction and the first direction D3 are referred to as side surfaces 230f and 230f.

The outer surface 230a of the core material 230 can be divided into a plurality of strip-shaped circumferential regions along the A3 direction, for example. For example, the outer surface 230a has two first circumferential regions 230b, four second circumferential regions 230c, and two third circumferential regions 230d.

The second circumferential region 230c is a circumferential region including the corner portion 231 of the core member 230 which is rectangular when viewed from the A3 direction. The first circumferential region 230b is a circumferential region of the main surface 230e excluding the second circumferential region 230c. The third circumferential region 230d is a circumferential region of the side surface 230f excluding the second circumferential region 230c.
When viewed from the A3 direction, the second circumferential region 230c includes the corner portion 231. Therefore, the mean curvature of the second circumferential region 230c is larger than the mean curvature of the first circumferential region 230b and the third circumferential region 230d. ..

[Oxide superconducting wire]
FIG. 17 is a plan view of the oxide superconducting wire 210.
A plurality of groove portions 207 are formed on the first main surface 10a of the oxide superconducting wire 210. The groove portion 207 is linear when viewed from the thickness direction (Z direction) of the oxide superconducting wire member 210. The groove portion 207 is inclined with respect to the X direction when viewed from the Z direction. The groove portion 207 is a second end portion in the width direction (X direction) of the first main surface 10a from the first side edge 10a1 which is one end portion in the width direction (X direction) of the first main surface 10a. It is formed over the two side edges 10a2. The plurality of groove portions 207 are formed at intervals in the length direction of the oxide superconducting wire member 10. An insulating layer wound with a polyimide tape or the like may be formed on the surface of the oxide superconducting wire 210 on which the groove 207 is formed.

The plurality of groove portions 207 includes a plurality of groove portion groups 207A. The groove group 207A has two adjacent grooves 207 and 207. The separation distance of the adjacent groove groups 207A and 207A in the Y direction is larger than the separation distance of the two groove portions 207 and 207 constituting one groove group 207A. In the superconducting conductor wire 220 shown in FIG. 14, the region between the two groove portions 207 and 207 constituting the groove portion group 207A is arranged so as to overlap the side surface 230f (see FIG. 16). The region between the adjacent groove groups 207A and 207A is arranged so as to overlap the main surface 230e (see FIG. 16).

As shown in FIGS. 14 and 15, the oxide superconducting wire 210 is spirally wound around the outer surface 230a of the core 230. The oxide superconducting wire 210 is wound around the core 230 so that the base material 1 is located on the outer peripheral side of the core 230 with respect to the oxide superconducting layer 3.

Butt winding is preferable as a form in which the oxide superconducting wire 210 is spirally wound around the core 230. The winding form of the oxide superconducting wire 210 may be single-layer winding or multi-layer winding. When the multi-layer winding is adopted, the winding form in which the upper layer covers the abutting portion of the lower layer among the two layers adjacent to each other in the thickness direction is possible.

The groove portion 207 is formed at a position where at least a part thereof overlaps the second circumferential direction regions 230c and 230c (see FIG. 16) when viewed from the thickness direction of the oxide superconducting wire member 210. For example, the groove portion 207 is located at a position where at least a part of the groove portion 207 overlaps the corner portion 231 (see FIG. 16) when viewed from the thickness direction of the oxide superconducting wire member 210. The groove portion 207 is formed along the A3 direction of the core material 230.

The oxide superconducting wire 210 may or may not be bonded to the outer surface 230a (see FIG. 16) of the core material 230. When the oxide superconducting wire 210 is adhered to the core 230, the oxide superconducting wire 210 can be adhered to the core 230 by solder, an adhesive or the like. Further, for example, a polyimide tape may be wound around the outer surface of the oxide superconducting wire 210 wound around the core material 230 to form an insulating layer.

[Manufacturing method of superconducting conductor wire] (second embodiment)
Hereinafter, an example of a method for manufacturing the superconducting conductor wire 220 will be described.

(First step: Formation of groove)
An oxide superconducting wire having the same configuration as that of the oxide superconducting wire 210 shown in FIG. 17 and a core material 230 (see FIG. 16) are prepared except that there is no groove 207.
A groove 207 (see FIG. 17) is formed in the oxide superconducting wire. As a result, the oxide superconducting wire 210 is obtained.

Examples of the method for forming the groove portion 207 include a method in which the groove portion forming device having a sharp blade portion is used and the blade portion is pressed against the surface of the oxide superconducting wire. As a method for forming the groove portion 207, mechanical polishing and etching are also possible. When the stabilizing layer 6 is formed by plating, it is also possible to form a mask layer on the surface to be formed to suppress the plating growth of the portion.
As the oxide superconducting wire, for example, a base material having a groove can be used. As a result, it is possible to form a groove having a shape along the groove of the base material in the stabilizing layer formed by plating on the base material.

(Second step: Winding of oxide superconducting wire)
As shown in FIGS. 14 and 15, the oxide superconducting wire 210 is wound around the surface of the core 230. The oxide superconducting wire 210 is wound around the core 230 so that the base material 1 is located on the outer peripheral side of the core 230 with respect to the oxide superconducting layer 3.

The oxide superconducting wire 210 is arranged so that at least a part of the groove 207 overlaps the second circumferential region 230c (see FIG. 16) when viewed from the thickness direction of the oxide superconducting wire 210. Wrap around. For example, the oxide superconducting wire 210 is wound around the core 230 so that at least a part of the groove 207 overlaps the corner 231 (see FIG. 16). As a result, the superconducting conductor wire 220 shown in FIGS. 14 and 15 is obtained. After the second step (winding of the oxide superconducting wire material) is completed, an insulating layer may be formed on the surface of the superconducting conductor wire 220.

[Effects of superconducting conductor wires]
Since the groove portion 207 is formed in the superconducting conductor wire 220, the oxide superconducting wire member 210 is easily bent at the portion where the groove portion 207 is formed. Therefore, the oxide superconducting wire 210 easily has a bent shape along the second circumferential region 230c of the core member 230.
When the core material 230 has a non-circular cross section (specifically, a rectangular shape), the superconducting conductor wire 220 is oxidized even at a location where the average curvature of the outer surface 230a of the core material 230 is large (second circumferential direction region 230c). The superconducting wire 210 is wound so as not to separate from the core 230.
At the location where the groove 207 is formed, the bending strain generated in the oxide superconducting wire 10 becomes small. Therefore, deterioration of superconducting characteristics can be suppressed.

In the superconducting conductor wire 220, since the oxide superconducting wire 210 is wound so as not to be separated from the core material 230, it is possible to suppress the oxide superconducting wire 210 from floating when an electromagnetic force, a thermal stress, or the like is applied. Therefore, deterioration of the oxide superconducting wire 210 due to floating (wire motion) can be suppressed.

In the superconducting conductor wire 220, it is not necessary to change the dimensions (for example, the thickness dimension) of the oxide superconducting wire 210, so that the dimensional accuracy of the oxide superconducting wire 210 can be improved.

[Effects of the superconducting conductor wire manufacturing method]
In the above-mentioned manufacturing method, since the groove portion 207 is formed in the oxide superconducting wire material 210 prior to winding the oxide superconducting wire material 210 around the core material 230, the work of forming the groove portion 207 is easy.

Although the present invention has been described above based on preferred embodiments, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present invention.
For example, FIG. 18 is a perspective view of the core material 330, which is another example of the core material. The core material 330 is a flat knit metal wire. The core material 330 has a non-circular shape (specifically, an oval shape or a race track shape) when viewed from the length direction. That is, the cross section of the core material 330 orthogonal to the length direction is a non-circular shape (specifically, an oval shape or a race track shape). The core material 330 is made of a metal such as copper or stainless steel.
The width of the core material 330 is, for example, 5 to 10 mm. The thickness of the core material 330 is, for example, 0.1 to 1 mm.

FIG. 19 is a schematic view of the groove portion 307, which is a first modification of the groove portion. The cross-sectional shape of the groove portion 307 (the cross-sectional shape orthogonal to the length direction of the groove portion 307) is V-shaped.
FIG. 20 is a schematic view of the groove portion 407, which is a second modification of the groove portion. The cross-sectional shape of the groove portion 407 (the cross-sectional shape orthogonal to the length direction of the groove portion 407) is rectangular.
FIG. 21 is a schematic view of the groove portion 507, which is a third modification of the groove portion. The cross-sectional shape of the groove portion 507 (the cross-sectional shape orthogonal to the length direction of the groove portion 507) is semicircular.

FIG. 22 is a perspective view of a superconducting magnet 600, which is an example of a superconducting device. The superconducting magnet 600 is configured by winding the superconducting conductor wire 20 (see FIG. 1) around the winding cylinder 602 of the winding frame 601. The winding frame 601 includes a winding cylinder 602 and collar portions 603 and 603.

The oxide superconducting wire according to the embodiment is wound around the core material so that the base material is located on the outer peripheral side of the core material with respect to the oxide superconducting layer. The oxide superconducting wire may be wound around the core material so that any main surface is located on the outer peripheral side, but the core is located on the outer peripheral side of the core material with respect to the oxide superconducting layer. It is preferably wrapped around the material.

1 ... Base material, 3 ... Oxide superconducting layer, 5 ... Superconducting laminate, 6 ... Stabilizing layer, 7,207,307,407,507 ... Groove, 10,210 ... Oxide superconducting wire, 30,230,330 ... Core material, 30a, 230a ... Outer surface, 30b, 230b ... First circumferential region, 30c, 230c ... Second circumferential region, 600 ... Superconducting magnet.

Claims (8)

A core material extending in one direction and a tape-shaped superconducting wire material spirally wound around the core material are provided.
The outer surface of the core material has a first circumferential direction region and a second circumferential direction region having a larger mean curvature than the first circumferential direction region when viewed from the length direction of the core material.
The superconducting wire material includes a superconducting laminate having at least a tape-shaped base material and a superconducting layer laminated on the base material.
A groove along the length direction of the core material is formed on the surface of the superconducting wire material.
The groove portion is a superconducting conductor wire formed at a position where at least a part thereof overlaps with a region in the second circumferential direction of the core material when viewed from the thickness direction of the superconducting wire material. The superconducting wire is wound around the core material so that the base material is located on the outer peripheral side with respect to the superconducting layer.
The superconducting conductor wire according to claim 1, wherein the groove portion is formed on the surface of the superconducting wire material on the base material side. The superconducting wire further includes a stabilizing layer covering the superconducting laminate.
The superconducting conductor wire according to claim 2, wherein the groove portion is formed on the surface of the stabilizing layer so as to reach the base material. The superconducting conductor wire according to any one of claims 1 to 3, wherein the depth D of the groove portion satisfies t / 10 ≦ D ≦ 2t / 3, where t is the thickness of the superconducting wire. The superconducting conductor wire according to any one of claims 1 to 4, wherein the shape of the groove is U-shaped in a cross section orthogonal to the length direction of the groove. A superconducting device configured by assembling the superconducting conductor wires according to any one of claims 1 to 5. The superconducting wire is obtained by using a core material extending in one direction and a tape-shaped superconducting wire having at least a tape-shaped base material and a superconducting laminate having a superconducting layer laminated on the base material. The first step of spirally winding around the core material and
It has a second step of forming a groove along the axial direction of the core material, and has.
The outer surface of the core material has a first circumferential direction region and a second circumferential direction region having a larger mean curvature than the first circumferential direction region when viewed from the length direction of the core material.
A method for manufacturing a superconducting conductor wire, wherein in the second step, the groove portion is formed at a position where at least a part of the groove portion overlaps the second circumferential direction region of the core material when viewed from the thickness direction of the superconducting wire material. A first step of forming a groove in a tape-shaped superconducting wire having a superconducting laminate having at least a tape-shaped base material and a superconducting layer laminated on the base material.
The second step of spirally winding the superconducting wire around the core material extending in one direction, and
The outer surface of the core material has a first circumferential direction region and a second circumferential direction region having a larger mean curvature than the first circumferential direction region when viewed from the length direction of the core material.
In the second step, the groove portion is arranged at a position along the length direction of the core material and at least a part of the groove portion overlaps the second circumferential direction region of the core material when viewed from the thickness direction of the superconducting wire material. A method of manufacturing a superconducting conductor wire.

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