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US4925502A
Expired / Lapsed
US
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Iron-cobalt type soft magnetic material
Assignee: Fujitsu Ltd
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Filing: 1988-09-07
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Granted: 1990-05-15
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Expires: 2008-09-07
Abstract
Abstract The iron-cobalt type soft magnetic material contains 35% to 60% by weight of cobalt, 0.03% to 2.0% by weight of aluminum, the remainder being iron, and is prepared by powder metallurgy.
Inventors
- 👤 Wataru Yamagishi
- 👤 Tsutomu Iikawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 03:31
CPC Classifications
H; H01; H01F; H01F1/00; H01F1/01; H01F1/03; H01F1/12; H01F1/14; H01F1/20; H01F1/22; C; C22; C22C; C22C33/00; C22C33/02; C22C33/0257; C22C33/0278; C22C33/0285
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
50 words
An iron-cobalt soft magnetic material consisting essentially of 35% to 60% by weight of cobalt, 0.03% to 2.0% by weight of aluminum, the remainder being iron, said iron-cobalt soft magnetic material being prepared by compacting and sintering a mixture comprising cobalt powder, iron-rich iron-cobalt powder, and aluminum or iron-aluminum powder.
Claim 2
Dependent Claim
50 words
An iron-cobalt soft magnetic material consisting essentially of 35% to 60% by weight of cobalt, 0.03% to 2.0% by weight of aluminum, the remainder being iron, said iron-cobalt soft magnetic material being prepared by compacting and sintering a mixture comprising cobalt powder, iron-rich iron-cobalt powder, and aluminum or iron-aluminum powder.
Claim 3
Dependent Claim
20 words
An iron-cobalt soft magnetic material as claimed in claim 1, wherein the cobalt content is 45% to 55% by weight.
Claim 4
Dependent Claim
20 words
An iron-cobalt soft magnetic material as claimed in claim 1, wherein the aluminum content is 0.1% to 1.0% by weight.
References Cited (Backward Citations)
US3891475A
Cited
JPS5475410A
Cited
JPS5559701A
Cited
JPS59136457A
Cited
JPS6089548A
Cited
EP0149281A2
Cited
JPS61253348A
Cited
JPS61291934A
Cited
JPS6254041A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-05-14 | 1993-11-13 | 1994-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-05-14 | 1997-11-13 | 1998-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-05-14 | 2001-11-13 | 2002-05-15 | $7700.00 | Window Closed / Lapsed |