Patent US2405914A successfully refreshed from Google Patents.
Patent US2744040A successfully refreshed from Google Patents.
US2744040A
Expired / Lapsed
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Process of preparing iron powder for magnetic cores
Assignee: GAF Chemicals Corp
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Filing: 1952-03-25
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Granted: 1956-05-01
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Expires: 1972-03-25
Abstract
No abstract record available.
Inventors
- 👤 George O Altmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:12
CPC Classifications
B; B22; B22F; B22F1/00; B22F1/10; B22F1/102; B22F1/14; B22F1/145
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
99 words
THE PROCESS OF IMPROVING THE ELECTROMAGNETIC PROPERTIES OF CARBONYL IRON POWDERS WHICH COMPRISES SUBJECTING COMMINUTED, PULVERULENT IRON POWDER OBTAINED BY THERMAL DECOMPOSITION OF PENTACARBONYL IRON HAVING A CARBON CONTENT OF AT LEAST 0.1% TO A COATING TREATMENT WITH A SILICONE RESIN, REDUCING THE TREATED POWDER WITH HYDROGEN AT A TEMPERATURE RANGING BETWEEN 450* C. AND 600* C. FOR A PERIOD OF TIME UNTIL THE CARBON CONTENT OF THE IRON POWDER IS REDUCED SO AS NOT TO EXCEED 0.05% BY WEIGHT OF THE TREATED POWDER, MIXING THE REDUCED POWDER WITH A BINDER AND THEN FORMING A CORE FROM SAID MIXTURE.
Claim 2
Dependent Claim
99 words
THE PROCESS OF IMPROVING THE ELECTROMAGNETIC PROPERTIES OF CARBONYL IRON POWDERS WHICH COMPRISES SUBJECTING COMMINUTED, PULVERULENT IRON POWDER OBTAINED BY THERMAL DECOMPOSITION OF PENTACARBONYL IRON HAVING A CARBON CONTENT OF AT LEAST 0.1% TO A COATING TREATMENT WITH A SILICONE RESIN, REDUCING THE TREATED POWDER WITH HYDROGEN AT A TEMPERATURE RANGING BETWEEN 450* C. AND 600* C. FOR A PERIOD OF TIME UNTIL THE CARBON CONTENT OF THE IRON POWDER IS REDUCED SO AS NOT TO EXCEED 0.05% BY WEIGHT OF THE TREATED POWDER, MIXING THE REDUCED POWDER WITH A BINDER AND THEN FORMING A CORE FROM SAID MIXTURE.
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) | 1959-05-01 | 1959-10-31 | 1960-05-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-05-01 | 1963-10-31 | 1964-05-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-05-01 | 1967-10-31 | 1968-05-01 | $7700.00 | Window Closed / Lapsed |