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Title: Mechanistic insights into the oxidation behavior of Ni alloys in high-temperature CO 2

Abstract

We present results of a Ni superalloy oxidized for short times in high purity CO 2 and similarly in Ar containing ≤ 1 ppb O 2. A detailed analysis of the oxidized surfaces reveals striking similarities for the two exposure environments, suggesting O 2 impurities control the oxidation process in high-temperature CO 2. Selective oxidation results in Cr-rich oxide layers grown by 2 outward diffusion, while Cr vacancies left in the metal contribute to significant void formation at the oxide/metal interface. Unlike for most of the alloy surface, the oxidation behavior of secondary phase metal carbides is considerably different in the two environments.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
National Energy Technology Lab. (NETL), Pittsburgh, PA, and Morgantown, WV (United States). In-house Research
Sponsoring Org.:
USDOE Office of Fossil Energy (FE)
OSTI Identifier:
1366428
Report Number(s):
NETL-PUB-20826
Journal ID: ISSN 0010-938X
Resource Type:
Journal Article
Resource Relation:
Journal Name: Corrosion Science; Journal Volume: 125
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Oleksak, Richard P., Baltrus, John P., Nakano, Jinichiro, Nakano, Anna, Holcomb, Gordon R., and Dogan, Omer N. Mechanistic insights into the oxidation behavior of Ni alloys in high-temperature CO2. United States: N. p., 2017. Web. doi:10.1016/j.corsci.2017.06.005.
Oleksak, Richard P., Baltrus, John P., Nakano, Jinichiro, Nakano, Anna, Holcomb, Gordon R., & Dogan, Omer N. Mechanistic insights into the oxidation behavior of Ni alloys in high-temperature CO2. United States. doi:10.1016/j.corsci.2017.06.005.
Oleksak, Richard P., Baltrus, John P., Nakano, Jinichiro, Nakano, Anna, Holcomb, Gordon R., and Dogan, Omer N. 2017. "Mechanistic insights into the oxidation behavior of Ni alloys in high-temperature CO2". United States. doi:10.1016/j.corsci.2017.06.005. https://www.osti.gov/servlets/purl/1366428.
@article{osti_1366428,
title = {Mechanistic insights into the oxidation behavior of Ni alloys in high-temperature CO2},
author = {Oleksak, Richard P. and Baltrus, John P. and Nakano, Jinichiro and Nakano, Anna and Holcomb, Gordon R. and Dogan, Omer N.},
abstractNote = {We present results of a Ni superalloy oxidized for short times in high purity CO2 and similarly in Ar containing ≤ 1 ppb O2. A detailed analysis of the oxidized surfaces reveals striking similarities for the two exposure environments, suggesting O2 impurities control the oxidation process in high-temperature CO2. Selective oxidation results in Cr-rich oxide layers grown by 2 outward diffusion, while Cr vacancies left in the metal contribute to significant void formation at the oxide/metal interface. Unlike for most of the alloy surface, the oxidation behavior of secondary phase metal carbides is considerably different in the two environments.},
doi = {10.1016/j.corsci.2017.06.005},
journal = {Corrosion Science},
number = ,
volume = 125,
place = {United States},
year = 2017,
month = 6
}
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