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Austenitic heat resisting steel

Assignee: JFE Engineering Corp
•
Filing: 1975-02-28
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Granted: 1976-02-24
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Expires: 1995-02-28
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Abstract

Abstract An austenitic heat resisting steel exhibiting excellent strength for a long period of time services at an elevated temperature, coexistant-adding 0.02 to 1.0% Nb and 0.02 to 1.9% Zr or 0.02 to 1.0% Nb, 0.02 to 1.0% Zr and 0.02 to 1.0% Ti in addition to usual composition of a stainless steel, simultaneously adjusting the atomic ratio of said(Nb+Zr) or (Nb+Zr+Ti) to C within the range of 0.05 to 1.0, preferably 0.2 to 0.5.

Inventors

  • 👤 Tohru Mimino
  • 👤 Kazuhisa Kinoshita
  • 👤 Takayuki Shinoda
  • 👤 Isao Minegishi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 23:09
CPC Classifications
C; C21; C21D; C21D6/00; C21D6/004; C22; C22C; C22C38/00; C22C38/18; C22C38/40; C22C38/48; C22C38/50

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 81 words
An austenitic heat resisting steel exhibiting excellent strength for a long period of time services at an elevated temperature consisting of the following composition; C: 0.03 to 0.30%, Si: up to 1.00%, Mn: up to 2.00%, Cr: 15.0 to 26.0%, Ni: 7.0 to 22.0%. 0.02 to 1% of each of Nb(containing Ta) and Zr wherein the atomic ratio of (Nb+Zr) to C is within the range of 0.05 to 1.0, preferably 0.2 to 0.5 unavoidable impurities and the balance being Fe.
Claim 2
Dependent Claim 81 words
An austenitic heat resisting steel exhibiting excellent strength for a long period of time services at an elevated temperature consisting of the following composition; C: 0.03 to 0.30%, Si: up to 1.00%, Mn: up to 2.00%, Cr: 15.0 to 26.0%, Ni: 7.0 to 22.0%. 0.02 to 1% of each of Nb(containing Ta) and Zr wherein the atomic ratio of (Nb+Zr) to C is within the range of 0.05 to 1.0, preferably 0.2 to 0.5 unavoidable impurities and the balance being Fe.
Claim 3
Dependent Claim 84 words
An austenitic heat resisting steel exhibiting excellent strength for a long period of time services at an elevated temperature consisting of the following composition: C: 0.03 to 0.30%, Si: up to 1.00%, Mn: up to 2.00%, Cr: 15.0 to 26.0%. Ni: 7.0 to 22.0% 0.02 to 1 % of each of Nb (containing Ta), Zr and Ti wherein the atomic ratio of (Nb+Zr+Ti) to C is within the range of 0.05 to 1.0, preferably, 0.2 to 0.5 unavoidable impurities and the balance being Fe.
Claim 4
Dependent Claim 84 words
An austenitic heat resisting steel exhibiting excellent strength for a long period of time services at an elevated temperature consisting of the following composition: C: 0.03 to 0.30%, Si: up to 1.00%, Mn: up to 2.00%, Cr: 15.0 to 26.0%. Ni: 7.0 to 22.0% 0.02 to 1 % of each of Nb (containing Ta), Zr and Ti wherein the atomic ratio of (Nb+Zr+Ti) to C is within the range of 0.05 to 1.0, preferably, 0.2 to 0.5 unavoidable impurities and the balance being Fe.

References Cited (Backward Citations)

US3607239A Cited
US3795509A Cited
US3716353A Cited
US3751244A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-02-23 1979-08-25 1980-02-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-02-23 1983-08-25 1984-02-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-02-23 1987-08-25 1988-02-24 $7700.00 Window Closed / Lapsed

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