Permanent magnet, motor, and generator

Patent metadata

Field	Value
Publication number	US-9502164-B2
Application number	US-201514661107-A
Country	US
Kind code	B2
Filing date	Mar 18, 2015
Priority date	Sep 24, 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 cell phase having a Th 2 Zn 17 crystal phase, a cell wall phase, an M-rich platelet phase formed vertically to a c-axis of the Th 2 Zn 17 crystal phase, and a Cu-rich platelet phase formed along the M-rich platelet phase.

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 cell phase having a Th 2 Zn 17 crystal phase, a cell wall phase formed to partition the Th 2 Zn 17 crystal phase, an M-rich platelet phase formed vertically to a c-axis of the Th 2 Zn 17 crystal phase and having a concentration of the element M higher than that of the cell phase, and a Cu-rich platelet phase formed along the M-rich platelet phase and having a Cu concentration higher than that of the cell phase.

2. The permanent magnet of claim 1 , wherein a number of the Cu-rich platelet phases existing in a region per 1 μm of a width of the metal structure in a direction vertical to the M-rich platelet phase is 10 or more and 70 or less.

3. The permanent magnet of claim 1 , wherein the Cu-rich platelet phase has a Sm concentration higher than that of the cell phase.

4. The permanent magnet of claim 1 , wherein the Cu-rich platelet phase has a CaCu 5 crystal phase.

5. The permanent magnet of claim 1 , wherein the Cu concentration in the Cu-rich platelet phase is 7.5 at % or more.

6. 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, and 50 at % or more of the element M in the composition formula is Zr.

7. 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 the group consisting of the group consisting of Ni, V, Cr, Mn, Al, Ga, Nb, Ta, and W.

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

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

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

11. The power generator of claim 9 , further comprising:
a stator; and
a rotor, arranged in the stator, comprising the permanent magnet.

12. A vehicle comprising the motor of claim 8 .

13. A vehicle comprising the power generator of claim 9 .

Assignees

• Toshiba Kk

Inventors

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

Classifications

• C22C19/07 Primary

  based on cobalt · CPC title

• C22C30/02

  containing copper · CPC title

• H01F1/055 Primary

  and magnetic transition metals, e.g. SmCo5 · CPC title

• H02K1/276

  Magnets embedded in the magnetic core, e.g. interior permanent magnets [IPM] · CPC title

• H01F1/0596

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