Effect of Zr Content on the Morphology and Emissivity of Surface Oxide Scales on FeCrAlY Alloys
The investigation aims at obtaining a life time extension of FeCrAlY heating elements by increasing the emissivity of the alumina surface scales. This approach will allow the use of a lower heating element temperature without decreasing the usable heat output. For this purpose, the oxidation mechani...
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Published in | Advanced engineering materials Vol. 18; no. 5; pp. 711 - 720 |
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Main Authors | , , , , , , |
Format | Journal Article |
Language | English |
Published |
Blackwell Publishing Ltd
01.05.2016
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Subjects | |
Online Access | Get full text |
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Summary: | The investigation aims at obtaining a life time extension of FeCrAlY heating elements by increasing the emissivity of the alumina surface scales. This approach will allow the use of a lower heating element temperature without decreasing the usable heat output. For this purpose, the oxidation mechanisms of Zr‐doped FeCrAlY model alloys were investigated. For thick specimens a high Zr addition is accompanied by an undesired rapid increase of the oxidation rate adversely affecting the life time of the component. However, for thin foil heating elements (typically 50–200 μm thickness) an optimized high Zr content might be a suitable concept for obtaining a high emissivity, because apparently, a dark appearing, high emissivity oxide may be obtained without occurrence of dramatic internal oxidation.
The investigation aims at obtaining a life time extension of FeCrAlY heating elements by increasing the emissivity of the alumina surface scales. It is shown that an optimized high Zr content might be a suitable concept for obtaining a high emissivity in thin foil heating elements. |
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Bibliography: | ArticleID:ADEM201500439 ark:/67375/WNG-H8FSPSWJ-D istex:7ED00F56B7917337646C2D636F92ECAF2272DE20 The authors would like to acknowledge the Deutsche Forschungsgemeinschaft (DFG) for funding this work (Priority program: SPP 1299 "HAUT"). The authors are grateful to the following colleagues in the Institute of Energy and Climate Research (IEK-2) of the Forschungszentrum Jülich GmbH for their assistance in the experimental work: H. Cosler, A. Kick, and R. Mahnke for the oxidation experiments, V. Gutzeit and J. Bartsch for metallographic studies, Dr. E. Wessel and Dr. D. Grüner for SEM investigations and Dr. L. Niewolak for assistance in the resistance heating tests. ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 1438-1656 1527-2648 |
DOI: | 10.1002/adem.201500439 |