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Title: Creep-Resistant, Al 2O 3- Forming Austenitic Stainless Steels

Abstract

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

Authors:
 [1];  [1];  [1];  [1];  [1];  [1];  [1];  [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Shared Research Equipment Collaborative Research Center
Sponsoring Org.:
FE USDOE - Office of Fossil Energy (FE)
OSTI Identifier:
931701
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Science; Journal Volume: 316; Journal Issue: 5823
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; AIR; ALLOYS; CREEP; ENERGY CONVERSION; LIFETIME; OXIDATION; RUPTURES; STABILIZATION; STAINLESS STEELS; WATER VAPOR; AUSTENITIC STEELS

Citation Formats

Yamamoto, Yukinori, Brady, Michael P, Lu, Zhao Ping, Maziasz, Philip J, Liu, Chain T, Pint, Bruce A, More, Karren Leslie, Meyer III, Harry M, and Payzant, E Andrew. Creep-Resistant, Al2O3- Forming Austenitic Stainless Steels. United States: N. p., 2007. Web. doi:10.1126/science.1137711.
Yamamoto, Yukinori, Brady, Michael P, Lu, Zhao Ping, Maziasz, Philip J, Liu, Chain T, Pint, Bruce A, More, Karren Leslie, Meyer III, Harry M, & Payzant, E Andrew. Creep-Resistant, Al2O3- Forming Austenitic Stainless Steels. United States. doi:10.1126/science.1137711.
Yamamoto, Yukinori, Brady, Michael P, Lu, Zhao Ping, Maziasz, Philip J, Liu, Chain T, Pint, Bruce A, More, Karren Leslie, Meyer III, Harry M, and Payzant, E Andrew. Mon . "Creep-Resistant, Al2O3- Forming Austenitic Stainless Steels". United States. doi:10.1126/science.1137711.
@article{osti_931701,
title = {Creep-Resistant, Al2O3- Forming Austenitic Stainless Steels},
author = {Yamamoto, Yukinori and Brady, Michael P and Lu, Zhao Ping and Maziasz, Philip J and Liu, Chain T and Pint, Bruce A and More, Karren Leslie and Meyer III, Harry M and Payzant, E Andrew},
abstractNote = {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},
doi = {10.1126/science.1137711},
journal = {Science},
number = 5823,
volume = 316,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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