US2940880A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of nitrogenization
Assignee: Standard Oil Co
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Filing: 1955-12-29
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Granted: 1960-06-14
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Expires: 1975-12-29
Abstract
No abstract record available.
Inventors
- 👤 James K Stanley
- 👤 George F Tisinai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:40
CPC Classifications
C; C23; C23C; C23C8/00; C23C8/06; C23C8/08; C23C8/24; C23C8/26
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
146 words
A PROCESS FOR CONVERTING FERRITIC IRON-CHROMIUMCARBON ALLOYS TO AUSTENTIC ALLOYS SUBSTANTIALLY FREE OF FERRITE WITHOUT INCORPORATING AUSTENITIZING AMOUNTS OF METALS EFFECTIVE THEREOF, SUCH AS NICKEL, MANGANESE, AND THE LIKE WHICH COMPRISES SUBJECTING A FERRITIC ALLOY CONSISTING ESSENTIALLY OF ABOUT 21% TO 33% CHROMIUM AND 0.1 TO 1.0% CARBON, THE BALANCE BEING IRON EXCEPT FOR INCIDENTAL IMPURITIES, TO ATMOSPHERE OF DRY MOLECULAR NITROGEN AT A TEMPERATURE IN THE RANGE OF FROM ABOUT 2000*F. TO 2400*F., MAINTAINING SAID ALLOY IN SAID ATMOSPHERE AT SAID TEMPERATURE FOR A PERIOD OF TIME SUFFICIENT TO INCORPORATE NITROGEN IN THE ALLOY TO CONVERTED IN AMOUNT IN THE RANGE OF 0.3 TO ABOUT 1.0% AND SUFFICIENT TO MAINTAIN THE RELATIVE PROPORTIONS OF NITROGEN TO CARBON FOR ANY PARTICULAR CHROMIUM CONTENT ABOVE THE LINE IN THE PHASE DIAGRAM OF THE ACCOMPANYING DRAWING, AND THEREAFTER COOLING THE ALLOY RAPIDLY TO A TEMPERATURE BELOW ABOUT 800*F.
Claim 2
Dependent Claim
146 words
A PROCESS FOR CONVERTING FERRITIC IRON-CHROMIUMCARBON ALLOYS TO AUSTENTIC ALLOYS SUBSTANTIALLY FREE OF FERRITE WITHOUT INCORPORATING AUSTENITIZING AMOUNTS OF METALS EFFECTIVE THEREOF, SUCH AS NICKEL, MANGANESE, AND THE LIKE WHICH COMPRISES SUBJECTING A FERRITIC ALLOY CONSISTING ESSENTIALLY OF ABOUT 21% TO 33% CHROMIUM AND 0.1 TO 1.0% CARBON, THE BALANCE BEING IRON EXCEPT FOR INCIDENTAL IMPURITIES, TO ATMOSPHERE OF DRY MOLECULAR NITROGEN AT A TEMPERATURE IN THE RANGE OF FROM ABOUT 2000*F. TO 2400*F., MAINTAINING SAID ALLOY IN SAID ATMOSPHERE AT SAID TEMPERATURE FOR A PERIOD OF TIME SUFFICIENT TO INCORPORATE NITROGEN IN THE ALLOY TO CONVERTED IN AMOUNT IN THE RANGE OF 0.3 TO ABOUT 1.0% AND SUFFICIENT TO MAINTAIN THE RELATIVE PROPORTIONS OF NITROGEN TO CARBON FOR ANY PARTICULAR CHROMIUM CONTENT ABOVE THE LINE IN THE PHASE DIAGRAM OF THE ACCOMPANYING DRAWING, AND THEREAFTER COOLING THE ALLOY RAPIDLY TO A TEMPERATURE BELOW ABOUT 800*F.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-06-14 | 1963-12-14 | 1964-06-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-06-14 | 1967-12-14 | 1968-06-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-06-14 | 1971-12-14 | 1972-06-14 | $7700.00 | Window Closed / Lapsed |