Patent US2890974A successfully refreshed from Google Patents.
US2890974A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Passivation of stainless steel alloys
Assignee: Fairchild Engine and Airplane Corp
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Filing: 1957-12-02
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Granted: 1959-06-16
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Expires: 1977-12-02
Abstract
No abstract record available.
Inventors
- 👤 Carlton E Carrigan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 23:51
CPC Classifications
C; C23; C23C; C23C22/00; C23C22/05; C23C22/68
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
49 words
A METHOD OF PASSIVATING A STAINLESS STEEL ALLOY WHICH COMPRISES IMMERSING THE ALLOY IN A PICKLING SOLUTION, RINSING, HEATING THE ALLOY AT A TEMPERATURE OF FROM ABOUT 700*F. TO ABOUT 800*F. IN AN OXIDIZING ATMOSPHERE, COOLING THE ALLOY AND REACTING THE ALLOY WITH HYDROGEN PEROXIDE UNTIL ALL REACTION CEASES.
References Cited (Backward Citations)
US2172428A
Cited
US2473456A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-06-15 | 1962-12-15 | 1963-06-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-06-15 | 1966-12-15 | 1967-06-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-06-15 | 1970-12-15 | 1971-06-16 | $7700.00 | Window Closed / Lapsed |