Creep-Resistant, Al₂O₃- Forming Austenitic Stainless Steels

Journal Article · Mon Jan 01 04:00:00 EST 2007 · Science

DOI:https://doi.org/10.1126/science.1137711· OSTI ID:931701

Yamamoto, Yukinori ^[1]; Brady, Michael P ^[1]; Lu, Zhao Ping ^[1]; Maziasz, Philip J ^[1]; Liu, Chain T ^[1]; Pint, Bruce A ^[1]; More, Karren Leslie ^[1]; Meyer, III, Harry M ^[1]; Payzant, E Andrew ^[1]

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1. ORNL

A family of inexpensive, Al2O3-forming, high creep strength austenitic stainless steels have been developed. The alloys are based on Fe-20Ni-14Cr-2.5 Al wt.%, with strengthening achieved via nanodispersions of NbC. These alloys offer the potential to significantly increase the operating temperatures of structural components, and can be used under the aggressive oxidizing conditions encountered in energy conversion systems. Protective Al2O3 scale formation was achieved at lower levels of Al in austenitic alloys than previously used, provided that the Ti and V alloying additions frequently used for strengthening were eliminated. The lower levels of Al permitted stabilization of the austenitic matrix structure, and made it possible to obtain excellent creep resistance. Creep rupture lifetime in excess of 2000 h at 750 aC and 100 MPa in air, and resistance to oxidation in air + 10% water vapor environments at 650 and 800 aC are demonstrated

• Research Organization: Oak Ridge National Laboratory (ORNL); Shared Research Equipment Collaborative Research Center
• Sponsoring Organization: FE USDOE - Office of Fossil Energy (FE)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 931701
• Journal Information: Science, Journal Name: Science Journal Issue: 5823 Vol. 316; ISSN 0193-4511; ISSN SCEHDK
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
AIR
ALLOYS
AUSTENITIC STEELS
CREEP
ENERGY CONVERSION
LIFETIME
OXIDATION
RUPTURES
STABILIZATION
STAINLESS STEELS
WATER VAPOR