Cryogenic regenerator material, regenerative cryocooler, and system including regenerative cryocooler

Patent metadata

Field	Value
Publication number	US-10101061-B2
Application number	US-201715443610-A
Country	US
Kind code	B2
Filing date	Feb 27, 2017
Priority date	Aug 19, 2016
Publication date	Oct 16, 2018
Grant date	Oct 16, 2018

Abstract

According to an embodiment, a cryogenic regenerator material contains a silver oxide. A molar ratio of silver atoms to oxygen atoms contained in the cryogenic regenerator material: Ag/O is 1.0 or more and 4.0 or less. The cryogenic regenerator material contains at least one selected from AgO, Ag2O and Ag3O as the silver oxide.

First claim

What is claimed is:

1. A regenerative cryocooler, comprising a cryogenic regenerator material comprising a silver oxide, the molar ratio of silver atoms to oxygen atoms contained in the cryogenic regenerator material: Ag/O being 1.0 or more and 4.0 or less.

2. The regenerative cryocooler of claim 1 , wherein the molar ratio of silver atoms to oxygen atoms contained in the cryogenic regenerator material: Ag/O is 1.8 or more and 3.2 or less.

3. The regenerative cryocooler of claim 1 , wherein the silver oxide is contained in a ratio of 50% by volume or more based on a whole volume of the cryogenic regenerator material.

4. The regenerative cryocooler of claim 1 , wherein the silver oxide is at least one selected from the group consisting of AgO, Ag 2 O and Ag 3 O.

5. The regenerative cryocooler of claim 1 , wherein the silver oxide comprises a first phase of silver oxide and a second phase of silver oxide having different crystal structures.

6. The regenerative cryocooler of claim 5 , wherein, assuming that A is a half width of a main peak of the first phase of silver oxide and B is a half width of a main peak of the second phase of silver oxide in a powder X-ray diffraction spectrum, the following condition is satisfied: A/B ≥1.2.

7. The regenerative cryocooler of claim 5 , wherein a crystal structure of the first phase of silver oxide is cubic, and a crystal structure of the second phase of silver oxide is hexagonal.

8. The regenerative cryocooler of claim 5 , wherein the first phase of silver oxide is Ag 2 O, and the second phase of silver oxide is Ag 3 O.

9. The regenerative cryocooler of claim 5 , wherein the first phase of silver oxide is present at the grain boundaries of the second phase of silver oxide.

10. The regenerative cryocooler of claim 1 , further comprising an Ag coating layer on a surface of the cryogenic regenerator material.

11. The regenerative cryocooler of claim 1 , further comprising at least one regenerator material selected from a copper alloy mesh and a stainless steel mesh.

12. A system comprising the regenerative cryocooler of claim 1 .

13. The regenerative cryocooler of claim 4 , wherein the silver oxide is AgO.

14. The regenerative cryocooler of claim 4 , wherein the silver oxide is Ag 2 O.

15. The regenerative cryocooler of claim 4 , wherein the silver oxide is Ag 3 O.

16. The system of claim 12 , wherein said system is a superconducting electromagnet apparatus.

17. The system of claim 12 , wherein said system is a magnetic resonance imaging (MRI) apparatus.

18. The system of claim 12 , wherein said system is a cryopump apparatus.

19. The system of claim 12 , wherein said system is a Josephson voltage standard system.

20. The system of claim 12 , wherein said system is a single-crystal pulling apparatus.

Assignees

• Toshiba Kk

Inventors

• Eguchi Tomoko
• Saito Akiko

Classifications

• F25B9/145 Primary

  pulse-tube cycle · CPC title

• C01P2002/74

  by peak-intensities or a ratio thereof only · CPC title

• C09K5/14 Primary

  Solid materials, e.g. powdery or granular · CPC title

• F25B2309/003

  characterised by construction or composition of the regenerator · CPC title

• F25B2309/1415

  Pulse-tube cycles characterised by regenerator details · CPC title