Patent US4140526A successfully refreshed from Google Patents.
US4140526A
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Ferritic stainless steel having improved weldability and oxidation resistance
Assignee: Nippon Stainless Steel Co Ltd
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Filing: 1977-11-07
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Granted: 1979-02-20
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Expires: 1997-11-07
Abstract
Abstract A ferritic stainless steel having improved weldability and oxidation resistance, consisting essentially of 11.0 - 20.0% by weight of Cr, less than 0.10% by weight of C, less than 1.5% by weight of Si, less than 1.5% by weight of Mn, less than 1.5% by weight of Zr, the ratio of (Zr%)/(C% + N%) being higher than 7, and the balance of Fe, and the nitrogen amount being restricted to less than 0.015% by weight.
Inventors
- 👤 Taishi Moroishi
- 👤 Isamu Koizumi
- 👤 Hisao Fujikawa
- 👤 Hirofumi Makiura
- 👤 Yuji Shoji
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 13:39
CPC Classifications
C; C22; C22C; C22C38/00; C22C38/18; C22C38/28
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
74 words
A Zr-containing ferritic stainless steel having improved weldability and oxidation resistance at high temperature, consisting of, in weight percent, Cr from 11.0 to 20.0, C less than 0.10, Si less than 1.5, Mn less than 1.5, Zr less than 1.5, Zr/(C+N) higher than 7, N less than 0.015, Fe and incidental impurities balance, and wherein the said amount of Zr is in excess of the stoichiometric amount of the total of C and N.
Claim 2
Dependent Claim
74 words
A Zr-containing ferritic stainless steel having improved weldability and oxidation resistance at high temperature, consisting of, in weight percent, Cr from 11.0 to 20.0, C less than 0.10, Si less than 1.5, Mn less than 1.5, Zr less than 1.5, Zr/(C+N) higher than 7, N less than 0.015, Fe and incidental impurities balance, and wherein the said amount of Zr is in excess of the stoichiometric amount of the total of C and N.
Claim 3
Dependent Claim
18 words
A Zr-containing ferritic stainless steel as defined in claim 1, in which C is from 0.001 to 0.10.
Claim 4
Dependent Claim
29 words
A Zr-containing ferritic stainless steel as defined in claim 1: Cr 17.99, C 0.042, si 0.60, Mn 0.57, Zr 0.93, Zr/(C+N) 19.0, N 0.007, fe and incidental impurities balance.
Claim 5
Dependent Claim
29 words
A Zr-containing ferritic stainless steel as defined in claim 1: Cr 16.58, C 0.004, si 0.51, Mn 1.41, Zr 0.21, Zr/(C+N) 23.3, N 0.005, fe and incidental impurities balance.
Claim 6
Dependent Claim
29 words
A Zr-containing ferritic stainless steel as defined in claim 1: Cr 18.07, C 0.037, si 0.73, Mn 0.51, Zr 0.37, Zr/(C+N) 8.4, N 0.007, fe and incidental impurities balance.
Claim 7
Dependent Claim
29 words
A Zr-containing ferritic stainless steel as defined in claim 1: Cr 18.06, C 0.029, si 0.70, Mn 0.49, Zr 0.34, Zr/(C+N) 9.7, N 0.006, fe and incidental impurities balance.
Claim 8
Dependent Claim
29 words
A Zr-containing ferritic stainless steel as defined in claim 1: Cr 17.80, C 0.031, si 0.89, Mn 0.48, Zr 0.58, Zr/(C+N) 15.3, N 0.007, fe and incidental impurities balance.
Claim 9
Dependent Claim
22 words
A Zr-containing ferritic stainless steel as defined in claim 1, in which the ratio of (Zr%)/(C% + N%) is higher than 10.
References Cited (Backward Citations)
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US3852063A
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Cited
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-02-19 | 1982-08-21 | 1983-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-02-19 | 1986-08-21 | 1987-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-02-19 | 1990-08-21 | 1991-02-20 | $7700.00 | Window Closed / Lapsed |