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Title: Oxidation of NiCr and NiCrMo Alloys at Low Temperatures
Oxidation of Ni-Cr and Ni-Cr-Mo was studied in operando with near ambient pressure x-ray photoelectron spectroscopy in the Cabrera-Mott regime. The oxidation temperature was 200°C—a severely diffusion-limited regime. The near-surface alloy is Cr-enriched after the reduction of native oxide in vacuum, and especially so for Ni-15Cr-6Mo. Mo-cations are integrated into the oxide and Mo(VI) dominates at the surface. The surface chemistry-driven promotion of chromia by Mo predicted by theory is negated by the limited surface diffusion of reactants. Preoxidation processing is proposed to control the oxide properties for the use of Ni-Cr superalloys at low temperatures.  more » « less
Award ID(s):
2004326
PAR ID:
10527136
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
Allen Press
Date Published:
Journal Name:
Corrosion
Volume:
79
Issue:
11
ISSN:
0010-9312
Page Range / eLocation ID:
1287 to 1296
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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