EP0187538A2
Expired / Lapsed
EP
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Permanent magnet and method for producing same
Assignee: TDK Corp
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Filing: 1985-12-30
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Granted: —
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Expires: 2005-12-30
Abstract
Abstract In the rare earth-iron-boron permanent magnet, Ce and La decrease the magnetic properties when used alone but synergistically enhance iHc when used in combination. The composition provided by the present invention is generally expressed by [(Ce x La l-x ) y R l-y ] x [(Fe l-u-w Co w M u ) l-v B v ] l-x with a proviso of 0.4 ≦ × ≦ 0.9,0.2<y≦1.0,0.05≦z≦ 0.3, 0.01 ≦ v ≦ 0.3, 0 ≦ u ≦ 0.2, 0 ≦ w ≦ 0.5, and M is at least one element selected from the group consisting of Aℓ, Ti, V, Cr, Mn, Zr, Hf, Nb, Ta, Mo, Ge, Sb, Sn, Bi, Ni, W, Cu, and Ag.
Inventors
- 👤 Kaneo Mohri
- 👤 Jiro Yamasaki
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 17:27
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: 9
Claim 1
Independent Claim
52 words
A permanent magnet having a composition expressed by (Ce x La 1-x ) z (Fe 1-v B v ) 1-z ' with a proviso of 0.4 1 x 1 0.9, 0.05 ≦ z ≦ 0.3, and 0.01 ≦ v ≦ 0.3 and having a coercive force (iHc) of at least 4 kOe.
Claim 2
Dependent Claim
52 words
A permanent magnet having a composition expressed by (Ce x La 1-x ) z (Fe 1-v B v ) 1-z ' with a proviso of 0.4 1 x 1 0.9, 0.05 ≦ z ≦ 0.3, and 0.01 ≦ v ≦ 0.3 and having a coercive force (iHc) of at least 4 kOe.
Claim 3
Dependent Claim
53 words
A permanent magnet according to claim 1, further containing at least one rare earth element (R) except for Ce and La, but including y, and expressed by L(Ce x La 1-x ) y R 1-y ] z (Fe 1-v B v ) 1-z , with a proviso of 0.2 < y < 1.0.
Claim 4
Dependent Claim
83 words
A permanent magnet according to claim 1, or 2, wherein Co is contained at an atomic ratio (w) and at least one element selected from the group consisting of Aℓ, Ti, V, Cr, Mn, Zr, Hf, Nb, Ta, Mo, Ge, Sb, Sn, Bi, Ni, W, Cu, and Ag is contained at an atomic ratio (u), wherein said (w) is from 0 to 0.5 and said (u) is from 0 to 0.2, with the proviso that sum of (u), (w) and Fe is 1.0.
Claim 5
Dependent Claim
53 words
A permanent magnet according to claim 1, 2, or 3, wherein B is partly replaced with at least one element selected from the group consisting of Si, C, P, N, Ge, and S in an atomic ratio of 0.5 or less based on a sum of B and said at least one element.
Claim 6
Dependent Claim
19 words
A permanent magnet according to claim 1, 2, 3, or 4, wherein said permanent magnet is a sintered magnet.
Claim 7
Dependent Claim
19 words
A permanent magnet according to claim 1, 2, 3, or 4, wherein said permanent magnet is a bonded magnet.
Claim 8
Dependent Claim
14 words
A permanent magnet according to claim 1, 2, 3, or 4, being plastically worked.
Claim 9
Dependent Claim
19 words
A permanent magnet according to claim 7, wherein the plastic working method is hot-pressing, swaging, extruding, forging, or rolling.
References Cited (Backward Citations)
No citation records indexed.
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