US3751244A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Austenitic heat resisting steel
Assignee: GIJUTSA KENKYUSHON NIPPON KOKA
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Filing: 1970-12-14
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Granted: 1973-08-07
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Expires: 1990-12-14
Abstract
Abstract Cr-Ni type austenitic heat resisting steel having about twice the heat resistibility of common stainless steel is provided by the addition of 0.001 to 0.30 percent by weight Ti, 0.001 to 0.30 percent by weight Nb + Ta, and 0.0001 to 0.05 percent by weight B to a well-known Cr-Ni type steel composition for elevated temperature service, and maintaining a specified balance of (Ti + 0.5 (Nb+Ta)) to C and a specified balance of Ti to (Ti+0.5 (Nb+Ta)).
Inventors
- 👤 T Mimino
- 👤 K Kinoshita
- 👤 I Minegishi
- 👤 T Shinoda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 19:07
CPC Classifications
C; C22; C22C; C22C38/00; C22C38/18; C22C38/40; C22C38/54; C22C38/48; C22C38/50
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
17 words
A steel of claim 1, wherein the ratio of Ti + 0.5(Nb+Ta)/C is from 0.6 to 2.6.
Claim 2
Dependent Claim
17 words
A steel of claim 1, wherein the ratio of Ti/Ti + 0.5(Nb+Ta) is from 0.15 to 0.75.
Claim 3
Dependent Claim
14 words
A steel of claim 1, wherein the Ti content is from 0.02 to 0.10.
Claim 4
Dependent Claim
14 words
A steel of claim 1, wherein the Nb+Ta content is from 0.02 to 0.23.
References Cited (Backward Citations)
US2190486A
Cited
US2562854A
Cited
US2602028A
Cited
US2793113A
Cited
US2801916A
Cited
US3303023A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-08-06 | 1977-02-05 | 1977-08-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-06 | 1981-02-05 | 1981-08-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-06 | 1985-02-05 | 1985-08-07 | $7700.00 | Window Closed / Lapsed |