Oxide superconducting wire and method of manufacturing the same

Patent metadata

Field	Value
Publication number	US-11267722-B2
Application number	US-201917268334-A
Country	US
Kind code	B2
Filing date	Dec 9, 2019
Priority date	Dec 28, 2018
Publication date	Mar 8, 2022
Grant date	Mar 8, 2022

Abstract

An oxide superconducting wire includes a superconducting layer deposited on a substrate. The superconducting layer includes an oxide superconductor RE-Ba—Cu—O and artificial pinning centers ABO 3 , where RE is a rare earth element, A is Ba, Sr or Ca, and B is Hf, Zr, or Sn. In a TEM image of a cross-section of the superconducting layer, a standard deviation σ of an inclination angle of the artificial pinning center rods with respect to a cross-sectional direction of the superconducting layer is 6.13° to 11.73° and an average length of the artificial pinning center rods is 19.84 to 25.44 nm.

First claim

The invention claimed is:

1. An oxide superconducting wire comprising:
a superconducting layer deposited on a substrate, wherein
the superconducting layer comprises:
an oxide superconductor comprising RE-Ba—Cu—O; and
artificial pinning center rods comprising ABO 3 , where
RE is a rare earth element,
A is Ba, Sr or Ca, and
B is Hf, Zr, or Sn, and

in a TEM image of a cross-section of the superconducting layer, a standard deviation n of an inclination angle of the artificial pinning center rods with respect to a cross-sectional direction of the superconducting layer is 6.13° to 11.73° and an average length of the artificial pinning center rods is 19.84 to 25.44 nm.

2. The oxide superconducting wire according to claim 1 , wherein a number density of the artificial pinning center rods in a plane perpendicular to the cross-sectional direction of the superconducting layer is 1000 to 3500 pieces/μm 2 .

3. The oxide superconducting wire according to claim 1 , wherein a ratio of a-axis oriented grains of the oxide superconductor calculated by an X-ray intensity ratio is 10% or less.

4. The oxide superconducting wire according to claim 1 , wherein a critical current density Jc at a temperature of 30K and a magnetic field of 2 T is 6.0 MA/cm 2 or more.

5. A method of manufacturing an oxide superconducting wire having a critical current density Jc of 6.0 MA/cm 2 or more in a magnetic field of 2 T in a c-axis direction at a temperature of 30K, the method comprising:
depositing, by a pulsed laser deposition method at a deposition rate of 23 nm/sec or more, a superconducting layer that comprises:
an oxide superconductor comprising RE-Ba—Cu—O; and
artificial pinning center rods comprising ABO 3 , where
RE is a rare earth element,
A is Ba, Sr or Ca, and
B is Hf, Zr or Sn.

6. The method of manufacturing an oxide superconducting wire according to claim 5 , wherein the deposition rate of the superconducting layer is 36 nm/sec or more.

7. The method of manufacturing an oxide superconducting wire according to claim 6 , wherein the deposition rate of the superconducting layer is 36 to 70 nm/sec.

8. The method of manufacturing an oxide superconducting wire according to claim 7 , wherein the deposition rate of the superconducting layer is 46 to 70 nm/sec.

9. The method of manufacturing an oxide superconducting wire according to claim 5 , wherein a number density of the artificial pinning center rods in a plane perpendicular to the cross-sectional direction of the superconducting layer is 1000 to 3500 pieces/μm 2 .

Assignees

• Fujikura Ltd

Inventors

• Hirata Wataru
• Fujita Shinji

Classifications

• C01P2006/40

  Electric properties · CPC title

• C01P2004/64

  Nanometer sized, i.e. from 1-100 nanometer · CPC title

• C04B2235/3248

  Zirconates or hafnates, e.g. zircon · CPC title

• C23C14/46

  by ion beam produced by an external ion source · CPC title

• C04B35/4504

  containing rare earth oxides · CPC title