US3969161A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cr-Ni system austenitic heat-resisting steel
Assignee: JFE Engineering Corp
•
Filing: 1974-02-11
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Granted: 1976-07-13
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Expires: 1994-02-11
Abstract
Abstract Cr-Ni system austenitic heat-resisting steel exhibiting higher heat resistance than that of well-known austenitic stainless steels by means of which an atomic ratio of C being 0.05 to 0.30% to Ti being 0.01 to 0.8% and/or Nb (Ta) being 0.01 to 1.6% is within the range of 1.3 to 7, preferably 3 to 6 and the grain size is within the range of ASTM No. 3 to 8.
Inventors
- 👤 Tohru Mimino
- 👤 Kazuhisa Kinoshita
- 👤 Takayuki Shinoda
- 👤 Isao Minegishi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 07:37
CPC Classifications
C; C22; C22C; C22C38/00; C22C38/18; C22C38/40; C22C38/50; C22C38/48
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
102 words
A Cr-Ni system austenitic heat-resisting steel consisting by weight substantially of C: 0.05 to 0.30%, Si: up to 1.0%, Mn: up to 2.0%, Cr: 15.0 to 26.0% Ni: 7.0 to 22.0%, and at least one of Ti: 0.01 to 0.8% and Nb: 0.01 to 1.7% and further, in the above contents, the atomic ratio of C to Ti and/or Nb is within the range of 1.3 to 7, which is calculated by the following formula: ##EQU2## where: wt% = weight % awt = atomic weight and the grain size of said steel is within the range of ASTM No. 3 to 8.
Claim 2
Dependent Claim
102 words
A Cr-Ni system austenitic heat-resisting steel consisting by weight substantially of C: 0.05 to 0.30%, Si: up to 1.0%, Mn: up to 2.0%, Cr: 15.0 to 26.0% Ni: 7.0 to 22.0%, and at least one of Ti: 0.01 to 0.8% and Nb: 0.01 to 1.7% and further, in the above contents, the atomic ratio of C to Ti and/or Nb is within the range of 1.3 to 7, which is calculated by the following formula: ##EQU2## where: wt% = weight % awt = atomic weight and the grain size of said steel is within the range of ASTM No. 3 to 8.
Claim 3
Dependent Claim
22 words
An austenitic heat-resisting steel as set forth in claim 1, wherein said C content is within the range of 0.08 to 0.30%.
Claim 4
Dependent Claim
22 words
An austenitic heat-resisting steel as set forth in claim 2 wherein said atomic ratio is within the range of 3 to 6.
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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) | 1979-07-13 | 1980-01-12 | 1980-07-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-07-13 | 1984-01-12 | 1984-07-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-07-13 | 1988-01-12 | 1988-07-13 | $7700.00 | Window Closed / Lapsed |