US3790414A
Expired / Lapsed
US
⏱️ 0.0 years remaining
As-CAST, RARE-EARTH-Co-Cu PERMANENT MAGNET MATERIAL
Assignee: Panasonic Holdings Corp
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Filing: 1968-11-14
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Granted: 1974-02-05
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Expires: 1988-11-14
Abstract
Abstract Permanent magnet material having a high coercive force and a high residual flux density is constituted by an alloy of cerium (15 to 20 mol percent), cobalt (52 to 77 mol percent) and copper (8 to 30 mol percent). The cerium can be replaced by Cemischmetal in an amount providing the equivalent quantity of cerium. The material has a novel microstructure. The material can be prepared by melting together the ingredient materials and furnace-cooling to room temperature. Superior results are obtained with specially scheduled heat-treatments including controlled cooling rates. It is not necessary to use fine particle magnet material.
Inventors
- 👤 Y Tawara
- 👤 H Senno
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 19:15
CPC Classifications
H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/032; H01F1/04; H01F1/047; C; C22; C22C; C22C19/00; C22C19/07; C22C28/00; H01F1/053; H01F1/055; H01F1/06
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
27 words
A magnetic composition according to claim 1 consisting essentially of an alloy of 15.25 mol percent cerium mischmetal, 67.8 mol percent Co and 16.95 mol percent Cu.
Claim 2
Dependent Claim
12 words
A permanent magnet according to claim 1 wherein said member is Ce.
Claim 3
Dependent Claim
35 words
A permanent magnet according to claim 3 wherein said alloy consists essentially of 17.1 to 17.43 mol percent of Ce, 64 to 72.6 mol percent of Co and 10.3 to 18.57 mol percent of Cu.
Claim 4
Dependent Claim
12 words
A permanent magnet according to claim 1 wherein said member is Ce-mischmetal.
Claim 5
Dependent Claim
35 words
A permanent magnet according to claim 5 wherein said alloy consists essentially of 17.1 to 17.43 mol percent of Ce-mischmetal, 64 to 72.6 mol percent of Co and 10.3 to 18.57 mol percent of Cu.
References Cited (Backward Citations)
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Cited
US3546030A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-02-04 | 1977-08-06 | 1978-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-04 | 1981-08-06 | 1982-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-04 | 1985-08-06 | 1986-02-05 | $7700.00 | Window Closed / Lapsed |