Patent US4276097A successfully refreshed from Google Patents.
US4276097A
Expired / Lapsed
US
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Method of treating Sm2 Co17 -based permanent magnet alloys
Assignee: United States Department of the Army
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Filing: 1980-05-02
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Granted: 1981-06-30
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Expires: 2000-05-02
Abstract
Abstract The reversible temperature coefficient of magnetization of a permanent magnet alloy over the temperature range from -50 degrees C. to +150 degrees C. is lowered by heat treating the alloy in a noble gas atmosphere or in a vacuum by the steps of (a) heating the alloy at about 1150 degrees C. for 1.5 hours (b) quenching the alloy in ice water, (c) heating the alloy at about 940 degrees C. for 2 hours, (d) lowering the temperature to about 700 degrees C. and heating for one hour, (e) lowering the temperature to about 600 degrees C. and heating for one hour, (f) lowering the temperature to about 500 degrees C. and heating for 2 hours, and (g) lowering the temperature to about 400 degrees C. and heating for 10 hours.
Inventors
- 👤 Robert L. Bergner
- 👤 Frederick Rothwarf
- 👤 Arthur Tauber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 21:00
CPC Classifications
H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/032; H01F1/04; H01F1/047; H01F1/053; H01F1/055
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
127 words
Method of lowering the reversible temperature coefficient of magnetization of a permanent magnet alloy, said method consisting of heat treating the alloy in an atmosphere selected from the group consisting of noble gas and vacuum by the steps of (a) heating the alloy at about 1150 degrees C. for 1.5 hours, (b) quenching the alloy in ice water, (c) heating the alloy at about 940 degrees C. for 2 hours, (d) lowering the temperature to about 700 degrees C. and heating for one hour, (e) lowering the temperature to about 600 degrees C. and heating for one hour, (f) lowering the temperature to about 500 degrees C. and heating for 2 hours, and (g) lowering the temperature to about 400 degrees C. and heating for 10 hours.
Claim 2
Dependent Claim
127 words
Method of lowering the reversible temperature coefficient of magnetization of a permanent magnet alloy, said method consisting of heat treating the alloy in an atmosphere selected from the group consisting of noble gas and vacuum by the steps of (a) heating the alloy at about 1150 degrees C. for 1.5 hours, (b) quenching the alloy in ice water, (c) heating the alloy at about 940 degrees C. for 2 hours, (d) lowering the temperature to about 700 degrees C. and heating for one hour, (e) lowering the temperature to about 600 degrees C. and heating for one hour, (f) lowering the temperature to about 500 degrees C. and heating for 2 hours, and (g) lowering the temperature to about 400 degrees C. and heating for 10 hours.
Claim 3
Dependent Claim
14 words
Method according to claim 1 wherein the alloy is heat treated in a vacuum.
Claim 4
Dependent Claim
16 words
Method according to claim 1 wherein the alloy is heat treated in a noble gas atmosphere.
Claim 5
Dependent Claim
11 words
Method according to claim 3 wherein the noble gas is argon.
Claim 6
Dependent Claim
18 words
Method according to claim 1 wherein said permanent magnet alloy is a Sm 2 Co 17 -based alloy.
Claim 7
Dependent Claim
28 words
Method according to claim 5 wherein said Sm 2 Co 17 -based alloy is Sm 2 Cu 1 .6 Zr 0 .16 Fe 3 .3 Co 12 .
Claim 8
Dependent Claim
132 words
Method of lowering the reversible temperature coefficient of magnetization of the permanent magnet alloy Sm 2 Cu 1 .6 Zr 0 .16 Fe 3 .3 Co 12 , said method consisting of heat treating the alloy in an argon atmosphere by the steps of (a) heating the alloy at about 1150 degrees C. for 1.5 hours, (b) quenching the alloy in ice water, (c) heating the alloy at about 940 degrees C. for 2 hours, (d) lowering the temperature to about 700 degrees C. and heating for one hour, (e) lowering the temperature to about 600 degrees C. and heating for one hour, (f) lowering the temperature to about 500 degrees C. and heating for 2 hours, and (g) lowering the temperature to about 400 degrees C. and heating for 10 hours.
Claim 9
Dependent Claim
132 words
Method of lowering the reversible temperature coefficient of magnetization of the permanent magnet alloy Sm 2 Cu 1 .6 Zr 0 .16 Fe 3 .3 Co 12 , said method consisting of heat treating the alloy in an argon atmosphere by the steps of (a) heating the alloy at about 1150 degrees C. for 1.5 hours, (b) quenching the alloy in ice water, (c) heating the alloy at about 940 degrees C. for 2 hours, (d) lowering the temperature to about 700 degrees C. and heating for one hour, (e) lowering the temperature to about 600 degrees C. and heating for one hour, (f) lowering the temperature to about 500 degrees C. and heating for 2 hours, and (g) lowering the temperature to about 400 degrees C. and heating for 10 hours.
References Cited (Backward Citations)
US4213802A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-06-29 | 1984-12-29 | 1985-06-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-06-29 | 1988-12-29 | 1989-06-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-06-29 | 1992-12-29 | 1993-06-30 | $7700.00 | Window Closed / Lapsed |