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US3769100A
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Method for manufacturing semi-hard magnetic material
Assignee: Akai Electric Co Ltd
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Filing: 1971-09-10
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Granted: 1973-10-30
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Expires: 1991-09-10
Abstract
Abstract Semi-hard magnetic Fe-Mn system alloys, prepared by powder metallurgical methods, are subjected to cold working and subsequent heat treatment to obtain a product of superior magnetic properties and relatively constant magnetic characteristics, as compared to those products prepared by conventional casting methods. The properties of these magnetic alloys render them suitable for use in hysteresis motors, mechanical channel elements employed in electrical communication systems and the like.
Inventors
- 👤 H Watanabe
- 👤 R Watanabe
- 👤 H Teramoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 05:06
CPC Classifications
C; C22; C22C; C22C33/00; C22C33/02; C22C33/0257; C22C33/0278; C22C33/0285; C22C38/00; C22C38/04; H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/032; H01F1/04; H01F1/06; H01F1/08; H01F1/086
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
28 words
The method of claim 1, wherein said powder mixture contains at least one additive powder selected from the group consisting of: Ti, Cu, V, Cr, Si and Co.
Claim 2
Dependent Claim
11 words
The method of claim 2, wherein said additive powder is Co.
Claim 3
Dependent Claim
20 words
The method of claim 1, wherein said cold working is effected at a working ratio of 40 - 65 percent.
Claim 4
Dependent Claim
22 words
The method of claim 1, wherein said heat treatment is effected at temperatures of 500* - 550* C.for 8 to 10 hours.
Claim 5
Dependent Claim
32 words
A magnet prepared by the method of claim 1 which is characterized by a residual magnetic flux density of greater than 9,500 Gauss and a coercive force of 10 - 150 Oersted.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-29 | 1977-04-30 | 1977-10-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-29 | 1981-04-30 | 1981-10-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-29 | 1985-04-30 | 1985-10-30 | $7700.00 | Window Closed / Lapsed |