US3679494A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Nitrided hafnium-tantalum alloys and method of making the same
Assignee: IIT Research Institute
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Filing: 1969-04-30
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Granted: 1972-07-25
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Expires: 1989-04-30
Abstract
Abstract IMPROVED ALLOYS OF HAFNIUM-TANTALUM SUITABLE FOR USE AS A CUTTING TOOL AND THE METHOD OF MAKING THE SAME. THE ALLOYS INCLUDE A NITRIDED CASE LAYER FORMED BY NITRIDING AT TEMPERATURES BETWEEN 2500*F. AND 4000*F. UNTIL THE NITRIDED LAYER IS AT LEAST 2 MILS THICK.
Inventors
- 👤 Vernon L Hill
- 👤 Harry R Nichols
- 👤 Alan L Hess
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 07:13
CPC Classifications
C; C23; C23C; C23C8/00; C23C8/06; C23C8/08; C23C8/24; C22; C22C; C22C27/00
Claims Analysis
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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) | 1975-07-25 | 1976-01-24 | 1976-07-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-25 | 1980-01-24 | 1980-07-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-25 | 1984-01-24 | 1984-07-25 | $7700.00 | Window Closed / Lapsed |