KR20170014616A - Superconducting Wires and Manufacturing method thereof - Google Patents

Abstract

The present invention relates to a manufacturing method of a superconductive wire, comprising: a process of manufacturing a mono filament formed of a superconductor; an assembling process of inserting a spacer formed of multiple mono filaments and conductors into a previously manufactured pipe-shaped multi-tube to manufacture a multi-filament; and a process of drawing the assembled multi-filament. The present invention can reduce manufacturing costs and maximize the properties of the superconductor due to uniform transformation of the mono filament during processing.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a superconducting wire,

The present invention relates to an NbTi superconducting wire and a manufacturing method thereof, and more particularly, to an NbTi superconducting wire composed of a plurality of superconducting monofilaments and a manufacturing method thereof.

In general, low-temperature superconducting wire is NbTi, Nb ₃ Sn, Nb ₃ Sn, Nb ₃ Al and, in a number to increase the efficiency without any loss due to the resistance to the main material, it is possible to flow a high current in a small area than the common metal line And has a remarkably superior current carrying capacity per unit area. Therefore, it has the advantage of making the power device smaller and lighter, and it is being produced for use in MRI equipment, NMR, energy storage device, magnetic levitation train, superconducting propulsion vessel as well as electric power transmission line.

Technologies for such a superconducting wire are disclosed in Japanese Unexamined Patent Publication Nos. 2001-151025, 2007-149494, and 2013-0345062.

The superconducting wire disclosed in Japanese Laid-Open Patent Publication No. 2012-151025 (Prior Art) is manufactured by forming an elongated hole into which a superconductor is inserted into a cylindrical base material, and charging the superconductor into an elongated hole by an extrusion process after a guddle process.

However, there is a problem in that the guddle process for forming a long hole is difficult to control the straightness and there is a limit in the interval between the holes, and a lot of machining defects are generated, thereby complicating the manufacturing process and requiring labor and time. In addition, expensive extrusion equipment has to be used, resulting in high manufacturing costs.

The present invention has been made in order to solve the problems of the conventional superconducting wire and the manufacturing method thereof as described above, and it is an object of the present invention to provide a superconducting wire and a method of manufacturing the same, which can reduce the manufacturing cost and uniformly deform the monofilament during processing, The present invention provides a superconducting wire and a manufacturing method thereof.

In order to achieve the above-mentioned object, the superconducting wire according to the present invention is characterized in that an annular core portion made of a conductor is formed in the center portion, and a plurality of monofilaments made of a superconductor are arranged at a predetermined interval in the circumferential direction A plurality of second superconductors arranged in a circumferential direction of the first superconducting layer and having a plurality of monofilaments formed of superconductors on the outer periphery of the first superconducting layer, And a conductor is filled in a space between the second superconductor groups and an outer periphery of the second superconductor groups.

In the superconducting wire according to the embodiment of the present invention, the second superconductor group may be composed of three or less monofilaments.

According to an aspect of the present invention, there is provided a method of manufacturing a superconducting wire, the method including: a step of preparing a monofilament with a superconductor; An assembling step of inserting a plurality of monofilaments and a spacer formed of a conductor into the tubular multi-tube thus manufactured to produce a multifilament; And a compression step of compressing the assembled multifilament to reduce the cross-sectional area.

In the method of manufacturing a superconducting wire according to the embodiment of the present invention, the multifilament can be drawn and processed in the compression step.

In the method of manufacturing a superconducting wire according to an embodiment of the present invention, in the assembling step, a plurality of spacers are annularly arranged at the center of the multi-tube to form a core portion, and a plurality of monofilaments are arranged in the circumferential direction And a plurality of mono filaments are arranged in a circumferential direction on the outer periphery of the first superconducting layer, and a plurality of second superconductors group having a plurality of monofilaments as one group are arranged in a circumferential direction It is also possible to arrange the first superconducting elements at predetermined intervals and insert spacers between the second superconducting elements.

In the method of manufacturing a superconducting wire according to an embodiment of the present invention, a plurality of spacers may be disposed outside the second superconductor groups in the assembling step.

In the method for manufacturing a superconducting wire according to an embodiment of the present invention, in the assembling step, one monofilament may be disposed in the center of the core portion.

In the method of manufacturing a superconducting wire according to an embodiment of the present invention, in the assembling step, a plurality of monofilaments and spacers may be stacked and filled in the multi-tube.

In the method of manufacturing a superconducting wire according to an embodiment of the present invention, it is also possible to insert a plurality of monofilaments and spacers on a jig and then insert the same into the multi-tube.

In the method of manufacturing a superconducting wire according to an embodiment of the present invention, the jig has an arc-shaped laminated groove, and the seating grooves on which the spacers are seated are formed at inner walls of the laminated grooves at predetermined intervals As shown in FIG.

In the method for manufacturing a superconducting wire according to an embodiment of the present invention, the lamination groove of the jig may be formed to have the same diameter as the inner diameter of the multi-tube.

In the method of manufacturing a superconducting wire according to an embodiment of the present invention, the conductor tube may be formed on the outer circumferential surface of the superconductor billet in the monofilament manufacturing process.

In the method of manufacturing a superconducting wire according to an embodiment of the present invention, the superconductor billet may include an NbTi billet.

In the method of manufacturing a superconducting wire according to an embodiment of the present invention, the superconductor billet may include an Nb sheet on the outer peripheral surface of the NbTi billet.

In the method of manufacturing a superconducting wire according to an embodiment of the present invention, the conductor tube may be formed of copper.

In the method of manufacturing a superconducting wire according to an embodiment of the present invention, the monofilament may be manufactured by at least one of an extrusion process and a drawing process in the monofilament manufacturing process.

In the method of manufacturing a superconducting wire according to an embodiment of the present invention, the spacer may be formed of copper and may be formed to have a diameter of 0.75 to 0.85 of the diameter of the monofilament.

In the method for manufacturing a superconducting wire according to an embodiment of the present invention, the multi-tube may be formed of copper.

As described above, the superconducting wire according to the present invention and the method of manufacturing the same can improve the low product recovery rate according to the expensive extrusion process, minimize the use of the extrusion equipment, reduce the manufacturing cost through the drawing process, It is possible to simplify the manufacturing process of the billet, thereby dispersing the compressive force acting on the monofilament during the drawing process, thereby achieving uniform deformation, thereby maximizing the superconducting characteristic.

1 is a cross-sectional view illustrating a superconducting wire according to an embodiment of the present invention.
2 is a flowchart illustrating a method of manufacturing a superconducting hull according to an exemplary embodiment of the present invention.
FIG. 3 and FIG. 4 are assembly diagrams of superconducting wire for explaining the assembling process shown in FIG. 2,
Fig. 5 is an exploded perspective view showing the monofilament shown in Figs. 3 and 4,
FIG. 6 is a cross-sectional view illustrating a fixture for assembling the superconducting wire shown in FIGS. 3 and 4. FIG.
7 is a cross-sectional view showing one example of the superconducting wire according to the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Referring to FIGS. 1, 3 and 4, the superconducting wire according to the embodiment of the present invention includes an annular core portion 110 formed at a central portion thereof, a first superconducting layer A plurality of second superconductors 130 are arranged at predetermined intervals along the circumferential direction on the outer periphery of the first superconducting layer 120, A space portion 140 is formed in the space and a skin layer 150 is formed on the outer periphery of the second superconductor group 130 and the space portion 140.

The core portion 110, the space portion 140, and the skin layer 150 are formed of a copper (cu) conductor.

The first superconducting layer 120 is formed by arranging a plurality of monofilaments 20 at predetermined intervals along the circumferential direction. Each monofilament 20 is formed of an NbTi superconductor.

The second superconductor group 130 includes a plurality of monofilaments 20 made of superconductors. In the present embodiment, the three monofilaments 20 constitute the second superconductor group 130.

A core portion 110 is formed at the center of the wire rod and a space portion 140 formed of copper is formed between the second superconductor groups 130. The first superconducting layer 120 and the second superconductor group 130 ) Of the respective monofilaments 20 uniformly appear even after the drawing process described later.

That is, the cross-section of the monofilament shows good conduction characteristics even after the drawing process, since the diameter is uniform along the longitudinal direction. The space between the core portion 110, which is the center of the wire rod, and the second superconductor group 130, It is formed as a conductor, so that even though the drawing process is performed, the uniformity is high without decreasing the local cross section.

One monofilament 20 is disposed at the center of the core 110.

Referring to FIGS. 1 to 6, a method of manufacturing a superconducting wire according to an embodiment of the present invention will be described.

First, the monofilament 20, the spacer 30, and the multi-tube 10 are manufactured.

The monofilament 20 is made of a superconductor NbTi as a main material, and the spacer 30 and the multi-tube 10 are made of copper, which is a conductor.

As shown in FIG. 5, each monofilament 20 is manufactured by forming a conductor tube 24 on the outer circumferential surface of the superconductor billet 21. The superconductor billet 21 is made of NbTi billets 22 in the shape of a bar and then coated with Nb on the outer peripheral surface of the NbTi billet 22 to form the Nb sheet 23. [ The conductor tube 24 is made of copper. The superconducting billet 21 on which the Nb sheet 23 is coated is fitted into the conductor tube 24 and assembled. At both ends of the superconductor billet 21, a copper plug 25 and a nose 26 are joined by electron beam welding (EB welding). Thereafter, the monofilament 20 is completed through extrusion processing and drawing processing.

The diameter of the superconductor billet 21 is compressed to 1/3 to 1/4 while being subjected to extrusion processing and drawing processing. In this compression process, the NbTi billet 22, the Nb sheet 23, and the conductor tube 24 are integrally joined together to form the monofilament 20.

The spacers 30 are manufactured to have a shape similar to that of the monofilaments 20 but smaller than the diameter of the monofilaments 20. For example, the spacers 30 are fabricated with 0.75-0.85 diameter of the monofilament 20. That is, the diameter of the spacer 30 is made 75 to 85% of the monofilament.

The multi-tube 10 is manufactured in a tubular shape having a plurality of monofilaments 20 and a hollow portion 11 in which a spacer 30 is inserted.

After the monofilament 20, the spacer 30 and the multi-tube 10 are manufactured, a plurality of monofilaments 20 and spacers 30 are inserted into the hollow portion 11 of the multi-tube 10 Process.

In the assembling step, the monofilaments 20 and the spacers 30 may be laminated by inserting the monofilaments 20 and the spacers 30 into the hollow portion 11 of the multi-tube 10, 10).

When directly stacking the multi-tube 10, a plurality of monofilaments 20 and spacers 30 are stacked on the hollow portion 11 of the multi-tube 10 from below so as to realize the laminated structure shown in Fig. . When the monofilament 20 and the spacer 30 are directly stacked on the hollow portion 11 of the multi-tube 10 as described above, the multi-tube 10 is easily slid to the inner wall of the hollow portion 11, It can be difficult.

3 and 4, a plurality of spacers 30 are annularly arranged at the center of the multi-tube 10 to form the core 110 of FIG. 1, The first superconducting layer 120 is formed by disposing a plurality of monofilaments 20 in the circumferential direction. A single monofilament 20 may be disposed at the center of the core 110 as needed.

A plurality of monofilaments 20 are disposed in the circumference of the first superconducting layer 120 in the circumferential direction and a plurality of second superconductor groups 130 having a plurality of monofilaments 20 as a group are arranged in the circumferential direction As shown in FIG.

Spacers 30 are inserted between the second superconductors 130. When the spacers 30 are disposed in the space between the second superconductors 130 arranged in a ring shape at a predetermined interval, the spacers 140 of FIG. 1 are formed after the drawing process. Sectional area of each monofilament 20 is uniformly deformed along the longitudinal direction by dispersing the compressive force acting between the monofilaments 20 by acting as a buffering material in the drawing process. As a result, the superconducting characteristics can be improved.

It is also possible to dispose a plurality of spacers 30 on the outer periphery of the second superconductor group 130 to form the skin layer 150 after the drawing process.

When the multilayer tube 10 is laminated on the outside of the multi-tube 10, the laminate structure can be easily realized by using the exclusive jig 1 to prevent slippage during lamination.

To this end, the jig 1 is provided with an arc-shaped laminated groove 2, and the seating grooves 3, on which the spacer 30 can be seated, are formed on the inner wall of the laminated groove 2, Respectively. It is preferable that the diameter of the seating groove 3 is formed to be equal to the diameter of the spacer 30 because the spacers 30 arranged at the outermost positions in the laminated structure are seated in the seating groove 3. [ The laminated grooves 2 are formed to have the same diameter as the inner diameter R of the multi-tube 10, so that the multi-tube 10 can be directly inserted into the laminated groove 2 to complete the assembly.

The monofilaments 20 and the spacer 30 are laminated so that the laminated structure shown in FIG. 3 is substantially realized starting from placing the spacer 30 on the seating groove 3 of the jig 1, . When a bundle of tiles is bundled and then inserted into the multi-tube 10, a large amount of tiles can be produced. After inserting the debris into the multi-tube 10, the bundling mechanism (for example, a cable tie) is removed.

When the multi-tube 10 is stacked and assembled, the assembled multifilaments are drawn and processed. In the drawing process, the cross-sectional area is reduced by compressing the multifilament.

On the other hand, the form of the lamination may be a shape close to a circle as shown in Fig. 3, or a polygonal shape as shown in Fig. Even if they are stacked in the form of a circle or stacked in a polygonal shape, if the drawing process is performed, a layout structure as shown in Fig. 1 can be obtained.

Drawing passes through multifilaments assembled with dice of a diameter smaller than that of the multifilaments shown in Figs. 3 and 4 to produce the superconducting wire having the diameter equal to the diameter of the die.

3 and 4, a spacer 30 made of a conductor is disposed at the center of the monofilaments 20 constituting the first superconducting layer 120, and a spacer is disposed between the second superconducting layers 130 When the drawing process is performed in a state, the interference between the monofilaments 20 in the drawing process is minimized, so that the compressive force acting on the monofilament 20 is dispersed, thereby allowing uniform deformation and maximizing the superconducting characteristic. .

The monofilaments 20 constituting the first superconducting layer 120 are not subjected to the interference of other monofilaments toward the core 110 and the monofilaments 20 constituting the second superconductors 130 are separated from the space 140, And the other monofilaments do not receive or receive the least amount of interference with other monofilaments.

7, a plurality of monofilaments 101 are concentrated at the central portion. In this structure, the cross-sectional area is locally reduced and thus the phenomenon of small sags occurs, It is the main cause. That is, when current is applied to the superconducting wire, a current exceeding a critical current flows to each monofilament, causing a quench. At this time, a resistance is generated at a portion where the cross-sectional area decreases, .

On the other hand, the number of the monofilaments 20 constituting the second superconductor group 130 is preferably 3 or less. Since the space portion 140 is formed on both sides of the second superconductor group 130, the monofilaments 20 at both ends do not interfere with other monofilaments 20 in both the space 140 and the skin layer 150, The monofilaments 20 arranged in the middle are subjected to interference of the monofilaments 20 at both ends. Accordingly, it is preferable to minimize the number of the monofilaments 20 arranged in the center and to increase the number of the second superconductors 130 according to the diameter of the superconducting wire. 3 and 4, the number of the second superconductors 130 composed of three monofilaments 20 is six, but the number of the second superconductors 130 can be increased or decreased according to the size of the superconducting wire.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It is obvious that the modification or the modification is possible by the person.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

10: Multi-tube
11: hollow part
20: monofilament
21: Superconductor billet
22: NbTi billet
23: Nb sheet
24: conductor tube
25: Plug
26: Nose
30: Spacer
110: core part
120: first superconducting layer
130: second superconductor group
140:
150: epidermal layer

Claims (6)

A plurality of monofilaments formed of superconductors are formed on the outer periphery of the core portion at predetermined intervals along the circumferential direction to form a first superconducting layer, A plurality of second superconducting groups each having a plurality of monofilaments of superconductors as a group are arranged at predetermined intervals along the circumferential direction, and a plurality of second superconductors arranged in a space between the second superconductor groups and the outer periphery of the second superconductor groups, Superconducting wire. The plasma display panel of claim 1, wherein the second superconductor group comprises:
Wherein the superconducting wire comprises three or less monofilaments. A step of producing a monofilament with a superconductor;
An assembling step of inserting a plurality of monofilaments and a spacer formed of a conductor into the tubular multi-tube thus manufactured to produce a multifilament; And
A compression step of drawing and drawing the assembled multifilament;
Wherein the superconducting wire is manufactured by a method comprising the steps of: 4. The method according to claim 3,
A plurality of spacers arranged in a ring shape in a central portion of the multi-tube to form a core portion, a plurality of monofilaments are arranged in a circumferential direction on an outer periphery of the core portion to form a first superconducting layer, A plurality of monofilaments are disposed in the circumferential direction, and a plurality of second superconductor groups each having a plurality of monofilaments as one group are arranged at predetermined intervals along the circumferential direction, and spacers are inserted between the second superconductor groups And the superconducting wire is disposed in the superconducting wire. 5. The method according to claim 4,
Wherein a plurality of monofilaments and spacers are stacked and filled in the multi-tube. 5. The method of claim 4,
Wherein the spacer inserted between the second superconductor groups comprises:
Wherein the diameter of the monofilament is 0.75-0.85.

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