Patent US3821031A successfully refreshed from Google Patents.
US3821031A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for manufacturing cold rolled steel having excellent drawability
Assignee: JFE Engineering Corp
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Filing: 1970-12-24
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Granted: 1974-06-28
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Expires: 1990-12-24
Abstract
Abstract A method for producing cold rolled drawing quality steels containing less than 0.01% C and less than 0.50% Mn in which an inert or decarburizing gas is blown through a molten steel which is then vacuum degassed, cast either into ingots or continuously cast, hot and cold rolled and then subjected to a rapid continuous anneal at a temperature of at least 650*C. When the aluminum-killed steel is produced, aluminum is added to said molten steel in a sufficient amount to provide more than 0.02% soluble aluminum in the steel, and the hot rolled steel is coiled at a temperature above 630*C to precipitate aluminum nitride.
Inventors
- 👤 H Kubotera
- 👤 Y Hashimoto
- 👤 T Shimomura
- 👤 N Tanaka
- 👤 K Matsudo
- 👤 M Ohkubo
- 👤 H Gonda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:19
CPC Classifications
C; C21; C21C; C21C7/00; C21C7/10; C21D; C21D8/00; C21D8/02; C21D8/04; C21D8/041; C21D8/0421; C21D8/0426
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
14 words
The method of claim 1 wherein said molten steel is cast as an ingot.
Claim 2
Dependent Claim
12 words
The method of claim 1 wherein said molten steel is continuously cast.
Claim 3
Dependent Claim
15 words
The method of claim 1 wherein said molten steel is blown with an inert gas.
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) | 1977-06-27 | 1977-12-27 | 1978-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-27 | 1981-12-27 | 1982-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-27 | 1985-12-27 | 1986-06-28 | $7700.00 | Window Closed / Lapsed |