Patent US3839102A successfully refreshed from Google Patents.
US3839102A
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Permanent magnet
Assignee: Panasonic Holdings Corp
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Filing: 1970-11-10
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Granted: 1974-10-01
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Expires: 1990-11-10
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 a fine particle magnet material.
Inventors
- 👤 Y Tawara
- 👤 H Senno
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:38
CPC Classifications
C; C22; C22C; C22C19/00; C22C19/07; C22C28/00; H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/032; H01F1/04; H01F1/047; H01F1/053; H01F1/055; H01F1/06
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
101 words
A METHOD FOR MAKING A PERMANENT MAGNET MATERIAL HAVING A FIBER-LIKE MICROSTRUCTURE OF FINENESS SMALLER THAN 20 MICRONS AND HAVING A MAXIMUM ENERGY PRODUCT OF AT LEAST 1,3 MG.OE, COMPRISING HEATING A MIXTURE OF 15 TO 20 MOL PERCENT OF CE OR CE MISCHMETAL, 52 TO 77 MOL PERCENT OF CO AND 8 TO 30 MOL PERCENT OF CU TO A METAL AT A TEMPERATURE HIGHER THAN 1200*C, QUENCHING SAID METAL TO ROOM TEMPERATURE, AGING THE QUENCHED ALLOY AT A TEMPERATURE OF 400*C TO 650*C FOR 20 MINUTES TO 10 HOURS AND THE RAPIDLY COOLING THE AGED ALLOY TO ROOM TEMPERATURE.
Claim 2
Independent Claim
101 words
A METHOD FOR MAKING A PERMANENT MAGNET MATERIAL HAVING A FIBER-LIKE MICROSTRUCTURE OF FINENESS SMALLER THAN 20 MICRONS AND HAVING A MAXIMUM ENERGY PRODUCT OF AT LEAST 1,3 MG.OE, COMPRISING HEATING A MIXTURE OF 15 TO 20 MOL PERCENT OF CE OR CE MISCHMETAL, 52 TO 77 MOL PERCENT OF CO AND 8 TO 30 MOL PERCENT OF CU TO A METAL AT A TEMPERATURE HIGHER THAN 1200*C, QUENCHING SAID METAL TO ROOM TEMPERATURE, AGING THE QUENCHED ALLOY AT A TEMPERATURE OF 400*C TO 650*C FOR 20 MINUTES TO 10 HOURS AND THE RAPIDLY COOLING THE AGED ALLOY TO ROOM TEMPERATURE.
Claim 3
Dependent Claim
16 words
A method for making a permanent magnet material according to claim 1, wherein Ce-mischmetal is employed.
Claim 4
Dependent Claim
16 words
A method for making a permanent magnet material according to claim 1 wherein Ce is employed.
References Cited (Backward Citations)
US3211592A
Cited
US3350240A
Cited
US3421889A
Cited
US3546030A
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US3523836A
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US3424578A
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US3560200A
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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) | 1977-09-30 | 1978-04-01 | 1978-10-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-30 | 1982-04-01 | 1982-10-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-30 | 1986-04-01 | 1986-10-01 | $7700.00 | Window Closed / Lapsed |