US3720504A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sintered steel-bonded hard metal alloy and a method of preparing the same
Assignee: Deutsche Edelstahlwerke AG
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Filing: 1970-10-16
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Granted: 1973-03-13
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Expires: 1990-10-16
Abstract
Abstract A SINTERED ALLOY OF THE TYPE COMPRISING A STEEL MATRIX AND ONE OR MORE METAL CARBIDES AND WHICH HAS HIGH ABRASION RESISTANCE, IS CHARACTERIZED BY THE PRESENCE OF FREE GRAPHITE IN THE STEEL MATRIX. SUCH SINTERED ALLOYS ARE OBTAINED BY A METHOD OF SINTERING IN WHICH THE SINTERED ALLOYS ARE MAINTAINED FOR AN EXTENDED PERIOD OF TIME AT SINTERING TEMPERATURES FOLLOWED BY CONTROLLED COOLING.
Inventors
- 👤 F Frehn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 07:16
CPC Classifications
C; C22; C22C; C22C29/00; C22C29/02; C22C29/06; C22C29/067
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-03-12 | 1976-09-11 | 1977-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-12 | 1980-09-11 | 1981-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-12 | 1984-09-11 | 1985-03-13 | $7700.00 | Window Closed / Lapsed |