This title appears in the Scientific Report :
2006
Effect of Component Thickness on Lifetime and Oxidation Rate of Chromia Forming Ferritic Steels in Low and High pO2-Environments
Effect of Component Thickness on Lifetime and Oxidation Rate of Chromia Forming Ferritic Steels in Low and High pO2-Environments
Long term oxidation tests were carried out with a high-Cr ferritic steel at 800 degrees C and 900 degrees C in simulated cathode and anode gas of a solid oxide fuel cell (air and an Ar/H-2/H2O mixture respectively). It was found that with decreasing sample thickness the life time of the steel decrea...
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Personal Name(s): | Huczkowski, P. |
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Ertl, S. / Piron-Abellan, J. / Christiansen, N. / Höfler, T. / Shemet, V. / Singheiser, L. / Quadakkers, W. J. | |
Contributing Institute: |
Werkstoffstruktur und Eigenschaften; IWV-2 |
Published in: | Materials at high temperatures, 22 (2006) S. 253 - 262 |
Imprint: |
Amsterdam [u.a.]
Elsevier Science
2006
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Physical Description: |
253 - 262 |
Document Type: |
Journal Article |
Research Program: |
Rationelle Energieumwandlung |
Series Title: |
Materials at High Temperatures
22 |
Subject (ZB): | |
Publikationsportal JuSER |
Long term oxidation tests were carried out with a high-Cr ferritic steel at 800 degrees C and 900 degrees C in simulated cathode and anode gas of a solid oxide fuel cell (air and an Ar/H-2/H2O mixture respectively). It was found that with decreasing sample thickness the life time of the steel decreases due to breakaway phenomena. This effect is caused by faster exhaustion of the chromium reservoir from the bulk alloy in the case of thinner components. During air exposure the oxidation rates increase with decreasing specimen thickness and this has to be taken into account in the calculation of the Cr-reservoir exhaustion. This thickness dependence is not found during the exposures in simulated anode gas. Hence, especially for thin walled components, the oxidation rates in anode gas are substantially smaller and thus the life times are longer than during air exposure. The differences in oxidation behaviour in the two environments are discussed on the basis of scale formation mechanisms involving microcrack formation in the surface oxide scale and depletion of major and minor alloying additions in the bulk alloy. |