Patent US3755007A successfully refreshed from Google Patents.
US3755007A
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US
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Stabilized permanent magnet comprising a sintered and quenched body of compacted cobalt-rare earth particles
Assignee: General Electric Co
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Filing: 1971-04-01
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Granted: 1973-08-28
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Expires: 1991-04-01
Abstract
Abstract A process for producing a novel cobalt-rare earth intermetallic permanent magnet material having a substantially stable magnetization at ambient temperatures above room temperature. A sintered cobalt-rare earth intermetallic product, in bulk or particulate form, is provided. The product is brought to quench temperature TQ ranging from about 750* C to 950* C and then it is fast cooled from said quench temperature TQ at a rate no less than about 75* C per minute to about room temperature.
Inventors
- 👤 M Benz
- 👤 D Martin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 19:33
CPC Classifications
C; C22; C22C; C22C1/00; C22C1/04; C22C1/0433; C22C1/0441; H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/032; H01F1/04; H01F1/047; H01F1/053; H01F1/055; H01F1/0555; H01F1/0557
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
40 words
A process for producing a sintered and quenched body of cobalt-rare earth intermetallic permanent magnet particles according to claim 1 wherein said sintered cobalt-rare earth intermetallic body is initially at about room temperature before being brought to quench temperature TQ.
Claim 2
Dependent Claim
43 words
A process for producing a sintered and quenched body of cobalt-rare earth intermetallic permanent magnet particles according to claim 1 wherein said sintered cobalt-rare earth intermetallic body is at the temperature at which it was sintered before being brought to quench temperature TQ.
Claim 3
Dependent Claim
50 words
A process for producing a sintered and quenched body of cobalt-rare earth intermetallic permanent magnet particles according to claim 1 wherein said sintered cobalt-rare earth intermetallic body is at a heat-aging temperature within 400* C below the temperature at which it was sintered before being brought to quench temperature TQ.
Claim 4
Dependent Claim
24 words
A process for producing a sintered and quenched body of cobalt-rare earth intermetallic permanent magnet particles according to claim 1 wherein R is samarium.
Claim 5
Dependent Claim
163 words
A process for producing a sintered and quenched body of cobalt-rare earth intermetallic permanent magnet pArticles having a substantially stable magnetization in air at ambient temperatures ranging from above room temperature up to about 150* C which comprises providing a sintered cobalt-rare earth intermetallic body of compacted cobalt-rare earth intermetallic particles, said sintered body having a density ranging from about 87 to 100 percent and consisting essentially of solid Co5R intermetallic phase and a precipitated solid CoR phase richer in rare earth metal content than said Co5R phase in an amount ranging from about 1 to 15 percent by weight of said body, where R is a rare earth metal or metals, bringing said body to a quench temperature TQ ranging from about 750* C to 950* C in an atmosphere in which it is substantially inert, and cooling said cobalt-rare earth body from said quench temperature TQ at a rate no less than about 75* C per minute to about room temperature.
Claim 6
Dependent Claim
11 words
A sintered and quenched body produced by the process of claim
Claim 7
Dependent Claim
12 words
A sintered and quenched body produced by the process of claim 6.
References Cited (Backward Citations)
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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) | 1976-08-27 | 1977-02-26 | 1977-08-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-27 | 1981-02-26 | 1981-08-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-27 | 1985-02-26 | 1985-08-28 | $7700.00 | Window Closed / Lapsed |