Patent US3278345A successfully refreshed from Google Patents.
US3278345A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing fine grained steel
Assignee: United States Steel Corp
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Filing: 1963-05-28
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Granted: 1966-10-11
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Expires: 1983-05-28
Abstract
No abstract record available.
Inventors
- 👤 Raymond A Grange
- 👤 Ronald S Mulhauser
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:18
CPC Classifications
C; C21; C21D; C21D8/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
86 words
A METHOD OF PRODUCING ULTRAFINE GRAIN SIZE IN STEELS HARDENABLE BY THERMOMECHANICAL TREATMENT COMPRISING RAPIDLY HEATING THE STEEL TO SLIGHTLY ABOVE ITS AC3 TEMPERATURE AND BEFORE ANY SUBSTANTIAL GRAIN GROWTH OCCURS, REDUCING THE CROSS SECTIONAL AREA THEREOF SUFFICIENTLY TO DEFORM SUBSTANTIALLY ALL OF THE GRAINS THEREOF RAPIDLY COOLING TO BELOW THE TRANSFORMATON RANGE OF THE STEEL AND REPEATING SUCH HEATING, REPEATING SAID WORKING AND COOLING A PLURALITY OF TIMES TO PRODUCE AN ULTRAFINE GRAIN SIZE AND FOLLOWING THE LAST WORKING, QUICKLY COOLING TO SUBSTANTIALLY ROOM TEMPERATURE.
Claim 2
Independent Claim
86 words
A METHOD OF PRODUCING ULTRAFINE GRAIN SIZE IN STEELS HARDENABLE BY THERMOMECHANICAL TREATMENT COMPRISING RAPIDLY HEATING THE STEEL TO SLIGHTLY ABOVE ITS AC3 TEMPERATURE AND BEFORE ANY SUBSTANTIAL GRAIN GROWTH OCCURS, REDUCING THE CROSS SECTIONAL AREA THEREOF SUFFICIENTLY TO DEFORM SUBSTANTIALLY ALL OF THE GRAINS THEREOF RAPIDLY COOLING TO BELOW THE TRANSFORMATON RANGE OF THE STEEL AND REPEATING SUCH HEATING, REPEATING SAID WORKING AND COOLING A PLURALITY OF TIMES TO PRODUCE AN ULTRAFINE GRAIN SIZE AND FOLLOWING THE LAST WORKING, QUICKLY COOLING TO SUBSTANTIALLY ROOM TEMPERATURE.
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) | 1969-10-10 | 1970-04-11 | 1970-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-10-10 | 1974-04-11 | 1974-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-10-10 | 1978-04-11 | 1978-10-11 | $7700.00 | Window Closed / Lapsed |