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US3950191A
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US
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Cold rolled steel sheets having an excellent enamelability and a method for producing said cold rolled steel sheets
Assignee: JFE Steel Corp
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Filing: 1974-10-21
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Granted: 1976-04-13
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Expires: 1994-10-21
Abstract
Abstract Steel sheets having an excellent enamelability are produced by adjusting the carbon, silicon, manganese, aluminum, oxygen and boron contents in a molten steel to be not more than 0.020% of carbon, not more than 0.03% of silicon, not more than 0.50% of manganese, not more than 0.010% of aluminum, nor more than 0.050% of oxygen, boron within a range of 0.003-0.020% being in such an amount B(%)×0(%) of more than 1×10.sup. -5 and the remainder being inevitable impurities and iron, and hot rolling the resulting steel, cold rolling the steel and subjecting to a recrystallization annealing in a conventional manner.
Inventors
- 👤 Kenji Ito
- 👤 Isao Takahashi
- 👤 Yo Ito
- 👤 Takuo Imai
- 👤 Fumio Kosumi
- 👤 Hideo Kuguminato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 13:12
CPC Classifications
C; C21; C21D; C21D8/00; C21D8/02; C21D8/0247; C21D8/0273; C22; C22C; C22C38/00; C21D3/00; C21D3/02; C21D3/04; C21D8/0221; C21D8/0236; C21D8/0257
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
105 words
A method for producing cold rolled steel sheets having an excellent enamelability which comprises adding to a molten steel containing not more than 0.020% of carbon, not more than 0.03% of silicon, not more than 0.50% of manganese, not more than 0.01% of aluminum, not more than 0.050% of oxygen, and having a nitrogen content of less than 0.01%, and the remainder being inevitable impurities and iron, boron within a range of 0.005-0.020% being in such amounts of B(%)×O(%) of more than 1×10 - 5 and hot rolling the resulting steel, cold rolling the steel, and subjecting to a recrystallization annealing under a decarburization atmosphere.
Claim 2
Independent Claim
105 words
A method for producing cold rolled steel sheets having an excellent enamelability which comprises adding to a molten steel containing not more than 0.020% of carbon, not more than 0.03% of silicon, not more than 0.50% of manganese, not more than 0.01% of aluminum, not more than 0.050% of oxygen, and having a nitrogen content of less than 0.01%, and the remainder being inevitable impurities and iron, boron within a range of 0.005-0.020% being in such amounts of B(%)×O(%) of more than 1×10 - 5 and hot rolling the resulting steel, cold rolling the steel, and subjecting to a recrystallization annealing under a decarburization atmosphere.
Claim 3
Dependent Claim
37 words
The method as claimed in claim 1, wherein upon the steel making, the carbon content is adjusted to 0.005-0.020% and at the recrystallization annealing, the decarburization is effected to reduce the carbon content to less than 0.005%.
Claim 4
Dependent Claim
13 words
The method as claimed in claim 1, wherein the boron content is 0.003-0.020%.
Claim 5
Dependent Claim
11 words
Cold rolled steel sheets made by the process of claim 1.
Claim 6
Dependent Claim
16 words
The cold rolled steel sheets as claimed in claim 4, wherein said boron content is 0.003-0.020%.
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) | 1979-04-13 | 1979-10-13 | 1980-04-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-04-13 | 1983-10-13 | 1984-04-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-04-13 | 1987-10-13 | 1988-04-13 | $7700.00 | Window Closed / Lapsed |