Permanent magnet, and motor and generator using the same

Patent metadata

Field	Value
Publication number	US-9773592-B2
Application number	US-201514661300-A
Country	US
Kind code	B2
Filing date	Mar 18, 2015
Priority date	Sep 13, 2013
Publication date	Sep 26, 2017
Grant date	Sep 26, 2017

Abstract

A permanent magnet of an embodiment includes: a composition represented by a composition formula: R(Fe p M q Cu r Co 1-p-q-r ) z , where R is at least one element selected from rare-earth elements, M is at least one element selected from Zr, Ti, and Hf, and relations of 0.3≦p≦0.4, 0.01≦q≦0.05, 0.01≦r≦0.1, and 7≦z≦8.5 (atomic ratio) are satisfied; and a structure including a cell phase having a Th 2 Zn 17 crystal phase, and a cell wall phase existing to surround the cell phase. An average magnetization of the cell wall phase is 0.2 T or less.

First claim

What is claimed is:

1. A permanent magnet, comprising:
a composition expressed by a composition formula:
R(Fe p M q Cu r Co 1-p-q-r ) z ,

where R is at least one element selected from the group consisting of rare-earth elements, M is at least one element selected from the group consisting of Zr, Ti, and Hf, p is a number, which is an atomic ratio, satisfying 0.3≦p≦0.4, q is a number, which is an atomic ratio, satisfying 0.01≦q≦0.05, r is a number, which is an atomic ratio, satisfying 0.01≦r≦0.1, and z is a number, which is an atomic ratio, satisfying 7≦z≦8.5; and
a structure including a cell phase having a Th 2 Zn 17 crystal phase, and a cell wall phase surrounding the cell phase,
wherein an average magnetization of the cell wall phase is 0.2 T or less,
the cell wall phase has a region in which a Cu concentration is 40 atomic % or more, and
a coercive force of the permanent magnet is 1330 kA/m or more, and a squareness ratio of the permanent magnet is 90.1% or more.

2. The permanent magnet of claim 1 , wherein the cell wall phase has a CaCu 5 crystal phase.

3. The permanent magnet of claim 1 , wherein 50 atomic % or more of the element R in the composition formula is Sm.

4. The permanent magnet of claim 1 , wherein 50 atomic % or more of the element M in the composition formula is Zr.

5. A motor, comprising the permanent magnet of claim 1 .

6. A power generator, comprising the permanent magnet of claim 1 .

7. The permanent magnet of claim 1 , wherein p is a number, which is an atomic ratio, satisfying 0.325≦p≦0.4.

8. The permanent magnet of claim 1 , wherein q is a number, which is an atomic ratio, satisfying 0.01≦q≦0.019.

9. The permanent magnet of claim 1 , wherein r is a number, which is an atomic ratio, satisfying 0.01≦r≦0.058.

10. The permanent magnet of claim 1 , wherein a residual magnetization of the permanent magnet is 1.208 T or more.

11. A permanent magnet, comprising:
a composition expressed by a composition formula:
R(Fe p M q Cu r (Co 1-s A s ) 1-p-q-r ) z ,

where R is at least one element selected from the group consisting of rare-earth elements, M is at least one element selected from the group consisting of Zr, Ti, and Hf, A is at least one element selected from the group consisting of Ni, V, Cr, Mn, Al, Si, Ga, Nb, Ta, and W, p is a number, which is an atomic ratio, satisfying 0.3≦p≦0.4, q is a number, which is an atomic ratio, satisfying 0.01≦q≦0.05, r is a number, which is an atomic ratio, satisfying 0.01≦r≦0.1, s is a number, which is an atomic ratio, satisfying 0≦s≦0.2, and z is a number, which is an atomic ratio, satisfying 7≦z≦8.5; and
a structure including a cell phase having a Th2Zn17 crystal phase, and a cell wall phase surrounding the cell phase,
wherein an average magnetization of the cell wall phase is 0.2 T or less,
the cell wall phase has a region in which a Cu concentration is 40 atomic % or more, and
a coercive force of the permanent magnet is 1330 kA/m or more, and a squareness ratio of the permanent magnet is 90.1% or more.

Assignees

• Toshiba Kk

Inventors

• Sakurada Shinya
• Horiuchi Yosuke
• Okamoto Keiko
• Hagiwara Masaya
• Kobayashi Tsuyoshi
• Endo Masaki
• Kobayashi Tadahiko

Classifications

• C22C1/00 Primary

  Making non-ferrous alloys (by electrothermic methods C22B4/00; by electrolysis C25C1/24, C25C3/36) · CPC title

• B22F9/04

  starting from solid material, e.g. by crushing, grinding or milling ({C22C1/1084 takes precedence}; crushing, grinding or milling, in general, see the relevant subclasses, e.g. B02C) · CPC title

• H01F1/086

  sintered · CPC title

• B22F3/02

  Compacting only · CPC title

• B22F2003/248

  Thermal after-treatment · CPC title