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Title: Effects of Minor Alloy Additions and Oxidation Temperature on Protective Alumina Scale Formation in Creep-Resistant Austenitic Stainless Steels

Abstract

Alumina scale formation in newly developed creep-resistant austenitic stainless steels was found to be sensitive to Al, Nb, Ti, and V content and oxidation temperature. Ti and V synergistically degraded the ability to form a protective alumina scale, whereas Nb was beneficial for alumina scale formation. The ability to form external alumina scales was lost in the lower Al and Nb containing alloys between 800 and 900 aC. Compositions with the potential to form alumina at 900 aC (and possibly higher) were identified.

Authors:
 [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:
978760
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Scripta Materialia; Journal Volume: 57; Journal Issue: 12
Country of Publication:
United States
Language:
English

Citation Formats

Brady, Michael P, Yamamoto, Yukinori, Santella, Michael L, and Pint, Bruce A. Effects of Minor Alloy Additions and Oxidation Temperature on Protective Alumina Scale Formation in Creep-Resistant Austenitic Stainless Steels. United States: N. p., 2007. Web. doi:10.1016/j.scriptamat.2007.08.032.
Brady, Michael P, Yamamoto, Yukinori, Santella, Michael L, & Pint, Bruce A. Effects of Minor Alloy Additions and Oxidation Temperature on Protective Alumina Scale Formation in Creep-Resistant Austenitic Stainless Steels. United States. doi:10.1016/j.scriptamat.2007.08.032.
Brady, Michael P, Yamamoto, Yukinori, Santella, Michael L, and Pint, Bruce A. Mon . "Effects of Minor Alloy Additions and Oxidation Temperature on Protective Alumina Scale Formation in Creep-Resistant Austenitic Stainless Steels". United States. doi:10.1016/j.scriptamat.2007.08.032.
@article{osti_978760,
title = {Effects of Minor Alloy Additions and Oxidation Temperature on Protective Alumina Scale Formation in Creep-Resistant Austenitic Stainless Steels},
author = {Brady, Michael P and Yamamoto, Yukinori and Santella, Michael L and Pint, Bruce A},
abstractNote = {Alumina scale formation in newly developed creep-resistant austenitic stainless steels was found to be sensitive to Al, Nb, Ti, and V content and oxidation temperature. Ti and V synergistically degraded the ability to form a protective alumina scale, whereas Nb was beneficial for alumina scale formation. The ability to form external alumina scales was lost in the lower Al and Nb containing alloys between 800 and 900 aC. Compositions with the potential to form alumina at 900 aC (and possibly higher) were identified.},
doi = {10.1016/j.scriptamat.2007.08.032},
journal = {Scripta Materialia},
number = 12,
volume = 57,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
  • A family of creep-resistant, Al2O3-forming austenitic (AFA) stainless steels was recently developed. The alloys exhibit excellent oxidation resistance up to 800 aC, but are susceptible to internal attack of Al at higher temperatures. In the present work, higher levels of Ni, Cr, Al, and Nb additions were found to correlate with improved oxidation behavior at 900 aC in air. The alloys generally appeared to be initially capable of external Al2O3 scale formation, with a subsequent transition to internal attack of Al (internal oxidation and internal nitridation) that is dependent on alloy composition. Compositional profiles at the alloy/scale interface suggest thatmore » the transition to internal oxidation is preceded by subsurface depletion of Al. Alloy design directions to increase the upper-temperature limit of protective Al2O3 scale formation in these alloys are discussed« less
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