Nano-scale corrosion mechanism of T91 steel in static lead-bismuth eutectic: a combined APT, EBSD, and STEM investigation
T91 steel is a candidate material for structural components in lead-bismuth-eutectic (LBE) cooled systems, for example fast reactors and solar power plants [1]. However, the corrosion mechanisms of T91 in LBE remain poorly understood. In this study, we have analysed the static corrosion of T91 in li...
Main Authors: | , , , , , , , |
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Format: | Journal article |
Language: | English |
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Elsevier
2024
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_version_ | 1811139280586670080 |
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author | Zhang, M He, G Lapington, M Zhou, W Short, MP Bagot, PAJ Hofmann, F Moody, MP |
author_facet | Zhang, M He, G Lapington, M Zhou, W Short, MP Bagot, PAJ Hofmann, F Moody, MP |
author_sort | Zhang, M |
collection | OXFORD |
description | T91 steel is a candidate material for structural components in lead-bismuth-eutectic (LBE) cooled systems, for example fast reactors and solar power plants [1]. However, the corrosion mechanisms of T91 in LBE remain poorly understood. In this study, we have analysed the static corrosion of T91 in liquid LBE using a range of characterisation techniques at increasingly smaller scales. A unique pattern of liquid metal intrusion was observed that does not appear to correlate with the grain boundary network. Upon closer inspection, electron backscatter diffraction (EBSD) reveals a change in the morphology of grains at the LBE-exposed surface, suggesting a local phase transition. Energy dispersive X-ray (EDX) maps show that Cr is depleted in the T91 material near the LBE interface. Furthermore, we observed the dissolution of all Cr-enriched precipitates in this region. Although the corrosion is conducted in an oxygen deficient environment, both scanning transmission electron microscopy (STEM) and atom probe tomography (APT) reveal a thin surface oxide layer (presumably wüstite) at the LBE-steel interface. Using electron energy loss spectroscopy (EELS) in the STEM, as well as APT, the atomic scale elemental redistribution and 3D morphology of the corrosion interface is investigated. By combining results from these different techniques, several types of oxide phases and structures can be identified. Based on this detailed nano-scale information, we propose potential mechanisms of T91 corrosion in LBE. |
first_indexed | 2024-09-25T04:03:35Z |
format | Journal article |
id | oxford-uuid:70c8881a-fbcc-4f43-a8e6-d289c77a082e |
institution | University of Oxford |
language | English |
last_indexed | 2024-09-25T04:03:35Z |
publishDate | 2024 |
publisher | Elsevier |
record_format | dspace |
spelling | oxford-uuid:70c8881a-fbcc-4f43-a8e6-d289c77a082e2024-05-16T07:20:50ZNano-scale corrosion mechanism of T91 steel in static lead-bismuth eutectic: a combined APT, EBSD, and STEM investigationJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:70c8881a-fbcc-4f43-a8e6-d289c77a082eEnglishSymplectic ElementsElsevier2024Zhang, MHe, GLapington, MZhou, WShort, MPBagot, PAJHofmann, FMoody, MPT91 steel is a candidate material for structural components in lead-bismuth-eutectic (LBE) cooled systems, for example fast reactors and solar power plants [1]. However, the corrosion mechanisms of T91 in LBE remain poorly understood. In this study, we have analysed the static corrosion of T91 in liquid LBE using a range of characterisation techniques at increasingly smaller scales. A unique pattern of liquid metal intrusion was observed that does not appear to correlate with the grain boundary network. Upon closer inspection, electron backscatter diffraction (EBSD) reveals a change in the morphology of grains at the LBE-exposed surface, suggesting a local phase transition. Energy dispersive X-ray (EDX) maps show that Cr is depleted in the T91 material near the LBE interface. Furthermore, we observed the dissolution of all Cr-enriched precipitates in this region. Although the corrosion is conducted in an oxygen deficient environment, both scanning transmission electron microscopy (STEM) and atom probe tomography (APT) reveal a thin surface oxide layer (presumably wüstite) at the LBE-steel interface. Using electron energy loss spectroscopy (EELS) in the STEM, as well as APT, the atomic scale elemental redistribution and 3D morphology of the corrosion interface is investigated. By combining results from these different techniques, several types of oxide phases and structures can be identified. Based on this detailed nano-scale information, we propose potential mechanisms of T91 corrosion in LBE. |
spellingShingle | Zhang, M He, G Lapington, M Zhou, W Short, MP Bagot, PAJ Hofmann, F Moody, MP Nano-scale corrosion mechanism of T91 steel in static lead-bismuth eutectic: a combined APT, EBSD, and STEM investigation |
title | Nano-scale corrosion mechanism of T91 steel in static lead-bismuth eutectic: a combined APT, EBSD, and STEM investigation |
title_full | Nano-scale corrosion mechanism of T91 steel in static lead-bismuth eutectic: a combined APT, EBSD, and STEM investigation |
title_fullStr | Nano-scale corrosion mechanism of T91 steel in static lead-bismuth eutectic: a combined APT, EBSD, and STEM investigation |
title_full_unstemmed | Nano-scale corrosion mechanism of T91 steel in static lead-bismuth eutectic: a combined APT, EBSD, and STEM investigation |
title_short | Nano-scale corrosion mechanism of T91 steel in static lead-bismuth eutectic: a combined APT, EBSD, and STEM investigation |
title_sort | nano scale corrosion mechanism of t91 steel in static lead bismuth eutectic a combined apt ebsd and stem investigation |
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