US3250648A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing hardened steel products
Assignee: United States Steel Corp
•
Filing: 1963-05-14
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Granted: 1966-05-10
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Expires: 1983-05-14
Abstract
No abstract record available.
Inventors
- 👤 Raymond A Grange
- 👤 James B Mitchell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 09:39
CPC Classifications
C; C21; C21D; C21D8/00; C21D8/02; C21D8/0221; C21D8/0226; C21D2211/00; C21D2211/008; C21D8/0231; C21D8/0247; C21D8/0252; Y; Y10; Y10S; Y10S277/00; Y10S277/935; Y10S277/939
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
87 words
A METHOD OF PRODUCING FLAT HEAT TREATMENT HARDENED STEEL SHEETS COMPRISING HOT ROLLING SUCH STEEL STRIP TO WITHIN 1 AND 20% OF THE DESIRED FINISHED GAUGE, THEREAFTER HEATING THE HOT ROLLED STRIP TO JUST SUBSTANTIALLY THE LOWEST TEMPERATURE AT WHICH THE MICROSTRUCTURE IS STABLE AUSTENITE, REDUCING THE GAUGE THEREOF BETWEEN 1 AND 20% TO THE DESIRED FINAL GAUGE AND SIMULTANEOUSLY QUENCHING THE STRIP TO A TEMPERATURE BELOW THE NOSE OF ITS ISOTHERMAL TRANSFORMATION CURVE AND THEN COOLING IT AT A RATE TO PRODUCE THE DESIRED MICROSTRUCTURE THEREIN.
Claim 2
Independent Claim
87 words
A METHOD OF PRODUCING FLAT HEAT TREATMENT HARDENED STEEL SHEETS COMPRISING HOT ROLLING SUCH STEEL STRIP TO WITHIN 1 AND 20% OF THE DESIRED FINISHED GAUGE, THEREAFTER HEATING THE HOT ROLLED STRIP TO JUST SUBSTANTIALLY THE LOWEST TEMPERATURE AT WHICH THE MICROSTRUCTURE IS STABLE AUSTENITE, REDUCING THE GAUGE THEREOF BETWEEN 1 AND 20% TO THE DESIRED FINAL GAUGE AND SIMULTANEOUSLY QUENCHING THE STRIP TO A TEMPERATURE BELOW THE NOSE OF ITS ISOTHERMAL TRANSFORMATION CURVE AND THEN COOLING IT AT A RATE TO PRODUCE THE DESIRED MICROSTRUCTURE THEREIN.
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) | 1969-05-09 | 1969-11-08 | 1970-05-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-05-09 | 1973-11-08 | 1974-05-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-05-09 | 1977-11-08 | 1978-05-10 | $7700.00 | Window Closed / Lapsed |