Permanent magnet, motor, and generator

Patent metadata

Field	Value
Publication number	US-9502165-B2
Application number	US-201514661119-A
Country	US
Kind code	B2
Filing date	Mar 18, 2015
Priority date	Sep 13, 2013
Publication date	Nov 22, 2016
Grant date	Nov 22, 2016

Abstract

A permanent magnet includes: a composition expressed by a composition formula: R p Fe q M r Cu t Co 100-p-q-r-t (R is at least one element selected from rare-earth elements, M is at least one element selected from Zr, Ti, and Hf, 10.5≦p≦12.5 at %, 23≦q≦40 at %, 0.88≦r≦4.5 at %, 4.5≦t≦10.7 at %); and a metal structure containing a Th 2 Zn 17 crystal phase and a Cu-rich phase having a Cu concentration higher than that of the Th 2 Zn 17 crystal phase. In a cross section including a c-axis of the Th 2 Zn 17 crystal phase, a number of intersections of the Cu-rich phases existing in an area of 1 μm square is 10 or more.

First claim

What is claimed is:

1. A permanent magnet comprising:
a composition expressed by a composition formula:
R p Fe q M r Cu t Co 100-p-q-r-t

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 satisfying 10.5≦p≦12.5 at %, q is a number satisfying 23≦q≦40 at %, r is a number satisfying 0.88≦r≦4.5 at %, and t is a number satisfying 4.5≦t≦10.7 at %; and
a metal structure containing a Th 2 Zn 17 crystal phase and a Cu-rich phase having a Cu concentration higher than that of the Th 2 Zn 17 crystal phase,
wherein a number of intersections of the Cu-rich phases existing in an area of 1 μm square in a cross section including a c-axis of the Th 2 Zn 17 crystal phase is 10 or more.

2. The permanent magnet of claim 1 , wherein the number of intersections is 120 or less.

3. The permanent magnet of claim 1 , wherein the Cu concentration in the Cu-rich phase is 30 at % or more.

4. The permanent magnet of claim 1 , wherein 50 at % or more of a total amount of the element R in the composition formula is Sm.

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

6. The permanent magnet of claim 1 , wherein 20 at % or less of Co in the composition formula is substituted by at least one element selected from among Ni, V, Cr, Mn, Al, Ga, Nb, Ta, and W.

7. A motor comprising the permanent magnet of claim 1 .

8. A power generator comprising the permanent magnet of claim 1 .

9. The motor of claim 7 , further comprising:
a stator; and
a rotor, arranged in the stator, comprising the permanent magnet.

10. The power generator of claim 8 , further comprising:
a stator; and
a rotor, arranged in the stator, comprising the permanent magnet.

11. A vehicle comprising the motor of claim 7 .

12. A vehicle comprising the power generator of claim 8 .

Assignees

• Toshiba Kk

Inventors

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

Classifications

• H01F1/0557 Primary

  sintered · CPC title

• H01F1/0596

  of rhombic or rhombohedral Th2Zn17 structure or hexagonal Th2Ni17 structure · CPC title

• H01F1/086

  sintered · CPC title

• B22F1/0085

  Operations & Transport · mapped topic

• C22C38/00

  Ferrous alloys, e.g. steel alloys (cast-iron alloys C22C37/00) · CPC title