Low-resistance connection body for high-temperature superconducting wire material and connection method

Patent metadata

Field	Value
Publication number	US-9941032-B2
Application number	US-201415116432-A
Country	US
Kind code	B2
Filing date	Oct 21, 2014
Priority date	Feb 4, 2014
Publication date	Apr 10, 2018
Grant date	Apr 10, 2018

Abstract

Provided is a low-resistance connection body for a high-temperature superconducting wire, in which a high-temperature superconducting bulk body and a high-temperature superconducting wire including a high-temperature superconducting layer are connected to each other, wherein a melting point of the high-temperature superconducting layer is higher than a melting point of the high-temperature superconducting bulk body; the high-temperature superconducting layer and the high-temperature superconducting bulk body are in contact at a connection site of the high-temperature superconducting wire and the high-temperature superconducting bulk body; and a surface of the high-temperature superconducting bulk body that is in contact with the high-temperature superconducting layer is crystallized due to crystal growth. Two high-temperature superconducting wires can be connected, with low resistance, through connection of the two high-temperature superconducting wires to one high-temperature superconducting bulk.

First claim

The invention claimed is:

1. A low-resistance connection body for a high-temperature superconducting wire, in which a high-temperature superconducting bulk body and a high-temperature superconducting wire including a high-temperature superconducting layer are connected to each other, wherein
a melting point of the high-temperature superconducting layer comprising REBa 2 Cu 3 O 7-δ is higher than a melting point of the high-temperature superconducting bulk body comprising RE′Ba 2 Cu 3 O 7-δ , each of RE and RE′ being one or a plurality of rare earth elements, and an element or composition of RE′ being different from that of RE;
the high-temperature superconducting layer and the high-temperature superconducting bulk body are in contact at a connection site of the high-temperature superconducting wire and the high-temperature superconducting bulk body; and
a surface of the high-temperature superconducting bulk body that is in contact with the high-temperature superconducting layer is crystallized into single crystal, and other portions of the high-temperature superconducting bulk body is crystallized into polycrystal due to crystal growth.

2. The low-resistance connection body for a high-temperature superconducting wire according to claim 1 , wherein the superconducting bulk body comprises RE′123 phase and RE′ 211 phase.

3. The low-resistance connection body for a high-temperature superconducting wire according to claim 1 , wherein the high-temperature superconducting wire comprises a stack of a substrate, the high-temperature superconducting layer, and a protection layer.

4. A low-resistance connection body for a high-temperature superconducting wire, in which a first high-temperature superconducting wire including a first high-temperature superconducting layer comprising RE 1 Ba 2 Cu 3 O 7-δ and a second high-temperature superconducting wire including a second high-temperature superconducting layer comprising RE 2 Ba 2 Cu 3 O 7-δ are connected to each other via a high-temperature superconducting bulk body comprising RE′Ba 2 Cu 3 O 7-δ , wherein
each of RE 1 , RE 2 , and RE′ being one or a plurality of rare earth elements, and an element or composition of RE′ being different from that of RE 1 or RE 2 ;
melting points of the first and second high-temperature superconducting layers are higher than a melting point of the high-temperature superconducting bulk body;
the first and second high-temperature superconducting layers and the high-temperature superconducting bulk body are in contact at connection sites of the first high-temperature superconducting wire and the second high-temperature superconducting layer of the second high-temperature superconducting wire and the high-temperature superconducting bulk body; and
surfaces of the high-temperature superconducting bulk body that are in contact with the first and second high-temperature superconducting layers are crystallized into single crystal, and other portions of the high-temperature superconducting bulk body is crystallized into polycrystal due to crystal growth.

5. The low-resistance connection body for a high-temperature superconducting wire according to claim 4 , wherein
the first high-temperature superconducting layer of the first high-temperature superconducting wire and the second high-temperature superconducting layer of the second high-temperature superconducting wire are connected at a same surface of the high-temperature superconducting bulk body.

6. The low-resistance connection body for a high-temperature superconducting wire according to claim 4 , wherein
the first high-temperature superconducting layer of the first high-temperature superconducting wire and the second high-temperature superconducting layer of the second high-temperature superconducting wire are connected at different surfaces of the high-temperature superconducting bulk body.

7. The low-resistance connection body for a high-temperature superconducting wire according to claim 4 , wherein
the first high-temperature superconducting layer of the first high-temperature superconducting wire and the second high-temperature superconducting layer of the second high-temperature superconducting wire are connected at the same surface of the high-temperature superconducting bulk body.

8. The low-resistance connection body for a high-temperature superconducting wire according to claim 4 , wherein
the first high-temperature superconducting layer of the first high-temperature superconducting wire and the second high-temperature superconducting layer of the second high-temperature superconducting wire are connected at different surfaces of the high-temperature superconducting bulk body.

9. The low-resistance connection body for a high-temperature superconducting wire according to claim 4 , wherein the superconducting bulk body comprises RE′123 phase and RE′ 211 phase.

10. The low-resistance connection body for a high-temperature superconducting wire according to claim 4 , wherein each of the first high-temperature superconducting wire and the second high-temperature superconducting wire comprises a stack of a substrate, a high-temperature superconducting layer, and a protection layer.

11. A low-resistance connection method for a high-temperature superconducting wire, for connecting a high-temperature superconducting wire including a high-temperature superconducting layer with a high-temperature superconducting bulk body, the melting point of which is lower than that of the high-temperature superconducting layer,
the method comprising:
a temperature rise step of heating the high-temperature superconducting bulk body comprising REBa 2 Cu 3 O 7-δ up to a temperature that is equal to or higher than a melting point of the high-temperature superconducting bulk body and lower than a melting point of the high-temperature superconducting layer comprising RE′Ba 2 Cu 3 O 7-δ , each of RE and RE′ being one or a plurality of rare earth elements, and an element or composition of RE′ being different from that of RE; and
a crystal growth step of performing crystal growth on the high-temperature superconducting bulk body in a state where a liquid phase portion of the high-temperature superconducting bulk body and the high-temperature superconducting layer are in contact with each other, the crystal growth leading to a formation of a single crystal at a contact surface of the high-temperature superconducting bulk body and a polycrystal at other portions of the high-temperature superconducting bulk body.

12. A low-resistance connection method for a high-temperature superconducting wire, for connecting a first high-temperature superconducting wire including a first high-temperature superconducting layer comprising RE 1 Ba 2 Cu 3 O 7-δ and a second high-temperature superconducting wire including a second high-temperature superconducting layer comprising RE 2 Ba 2 Cu 3 O 7-δ with a high-temperature superconducting bulk body comprising RE′Ba 2 Cu 3 O 7-δ , the melting point of which is lower than those of the first high-temperature superconducting layer and the second high-temperature superconducting layer, each of RE 1 , RE 2 , and RE′ being one or a plurality of rare earth elements, and an element or composition of RE′ being different from that of RE 1 or RE 2 ; the method comprising:
a temperature rise step of heating the high-temperature superconducting bulk body up to a temperature that is equal to or higher than a melting point of the high-temperature superconducting bulk body and lower than melting points of the first and second high-temperature superconducting layers; and
a crystal growth step of performing crystal growth on the high-temperature superconducting bulk

Assignees

• Riken

Inventors

• Jin Xinzhe
• Maeda Hideaki
• Yanagisawa Yoshinori

Classifications

• H01R43/02

  for soldered or welded connections · CPC title

• H01R4/68 Primary

  Connections to or between superconductive connectors · CPC title

• H01F6/06

  Coils, e.g. winding, insulating, terminating or casing arrangements therefor · CPC title

• H01B12/04 Primary

  Single wire · CPC title

• H01L39/02

  Electricity · mapped topic