EP0216254A1
Expired / Lapsed
EP
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Permanent magnet
Assignee: Toshiba Corp
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Filing: 1986-09-10
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Granted: —
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Expires: 2006-09-10
Abstract
Abstract A permanent magnet according to the present invention is characterized in that it is composed of an alloy comprising mainly of iron, and R (at least one element from rare earth element and yttrium), cobalt, and boron as the remainder, wherein the alloy is formed principally of ferromagnetic Fe-rich phase of tetragonal system and includes a nonmagnetic laves phase. Compared with the prior rare earth-Fe based magnet, it has higher Curie temperature and has excellent magnetic characteristics, especially the temperature characteristics.
Inventors
- 👤 Tetsuhiko Mizoguchi
- 👤 Isao Sakai
- 👤 Hiromi Niu
- 👤 Koichiro Inomata
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 14:54
CPC Classifications
H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/032; H01F1/04; H01F1/047; H01F1/053; H01F1/055; H01F1/057; H01F1/0571; H01F1/0575; H01F1/0577
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
56 words
A permanent magnet formed of a sintered alloy having largist amount of iron and including cobalt, boron, and material R consisting of at least one element from the group of rare earth element and yttrium, wherein said sintered body is formed principally of a ferromagnetic Fe-rich phase of tetragonal system and includes a nonmagnetic laves phase.
Claim 2
Dependent Claim
56 words
A permanent magnet formed of a sintered alloy having largist amount of iron and including cobalt, boron, and material R consisting of at least one element from the group of rare earth element and yttrium, wherein said sintered body is formed principally of a ferromagnetic Fe-rich phase of tetragonal system and includes a nonmagnetic laves phase.
Claim 3
Dependent Claim
18 words
The permanent magnet according to claim l, wherein the laves phase of the alloy is substantially entirely nonmagnetic.
Claim 4
Dependent Claim
20 words
The permanent magnet according to claim l, wherein the content of said laves phase is 2 to l0% by volume.
Claim 5
Dependent Claim
42 words
The permanent magnet according to claim l, wherein said alloy comprises a composition system of l0 to 40% by weight of R, 0.l to 8% by weight of B, l to 23% by weight of Co, and the remainder substantially of Fe.
Claim 6
Dependent Claim
28 words
The permanent magnet according to claim 4, wherein said alloy further includes 0.l to 5% by weight of at least one element from the group Al and Ga.
Claim 7
Dependent Claim
19 words
The permanent magnet according to claim 4, wherein said alloy further includes 0.l to 5% by weight of Al.
Claim 8
Dependent Claim
21 words
The permanent magnet according to claim 4, wherein the content of B in said alloy is 0.8 to 0.95% by weight.
Claim 9
Dependent Claim
35 words
The permanent magnet according to claim 6, wherein at least more than 70% by weight of at least one element from the group Al and Ga in said alloy is included in said Fe-rich phase.
Claim 10
Dependent Claim
35 words
The permanent magnet according to claim 8, wherein at least more than 80% by weight of at least one element from the group Al and Ga in said alloy is included in said Fe-rich phase.
Claim 11
Dependent Claim
53 words
l0. An alloy for permanent magnet having largest amount of iron, and including cobalt, boron and material R consisting of at least one element from the group of rare earth element and yttriums wherein said alloy is formed principally of a ferromagnetic Fe-rich phase of tetragonal system and includes a nonmagnetic laves phase.
Claim 12
Dependent Claim
53 words
l0. An alloy for permanent magnet having largest amount of iron, and including cobalt, boron and material R consisting of at least one element from the group of rare earth element and yttriums wherein said alloy is formed principally of a ferromagnetic Fe-rich phase of tetragonal system and includes a nonmagnetic laves phase.
Claim 13
Dependent Claim
17 words
The alloy according to claim l0, wherein the laves phase of the alloy is substaintially entirely nonmagnetic.
Claim 14
Dependent Claim
19 words
The alloy according to claim l0, wherein the content of said laves phase is 2 to l0% by volume.
Claim 15
Dependent Claim
41 words
The permanent magnet alloy according to claim l0 which comprises a composition system of l0 to 40% by weight of R, 0.l to 8% by weight of B, l to 23% by weight of Co, and the remainder substantially of Fe.
Claim 16
Dependent Claim
27 words
The permanent magnet alloy according to claim l2 which further includes 0.l to 5% by weight at least one element from the group of Al and Ga.
Claim 17
Dependent Claim
18 words
The permanent magnet alloy according to claim l2 which further includes 0.l to 5% by weight of Al.
Claim 18
Dependent Claim
20 words
The permanent magnet alloy according to claim l3, in which the content of B is 0.8 to 0.95% by weight.
Claim 19
Dependent Claim
24 words
The permanent magnet alloy according to claim l5, wherein at least more than 70% by weight of Al is included in said Fe-rich phase.
Claim 20
Dependent Claim
24 words
The permanent magnet alloy according to claim l7, wherein at least more than 80% by weight of Al is included in said Fe-rich phase.
Claim 21
Dependent Claim
16 words
The permanent magent alloy according to claim l, wherein (BH) max is 30 MGOe or more.
Claim 22
Dependent Claim
16 words
The permanent magnet alloy according to claim l0, wherein (BH) max is 30 MGOe or more.
References Cited (Backward Citations)
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