Microstructures of oxide films formed in alloy 182 BWR core shroud support leg cracksShow others and affiliations
2018 (English)In: Miner. Met. Mater. Ser., 2018, p. 417-431Conference paper, Published paper (Refereed)
Abstract [en]
This paper contributes to a TEM examination on the oxide films formed at three locations along a crack path in Alloy 182 weld from a BWR core shroud support leg, namely, the crack mouth, the midway between the mouth and the crack tip, and the crack tip. In the crack mouth the oxide film was approximately 1.6 μm in thickness and consisted of relatively pure NiO. The midway oxide film was mainly a nickel chromium oxide with a film thickness of 0.3 μm. At the crack tip the oxide film was a nickel chromium iron oxide with a film thickness of 30 nm. In all studied locations the main oxides had the similar rocksalt structure and the cracks were much wider than the thicknesses of the oxide films. It probably suggests that the corroded metal was largely dissolved into the coolant. The different dissolution rates of nickel, chromium and iron cations in the oxide films are clearly displayed with the compositions of the residual oxides. The oxide stability under different redox potentials along the crack path is briefly discussed.
Place, publisher, year, edition, pages
2018. p. 417-431
Keywords [en]
BWR, Core shroud, Crack, FIB, Oxide microstructure, SEM, Support leg, TEM, Boiling water reactors, Chromium, Chromium compounds, Crack propagation, Crack tips, Cracks, Film thickness, Iron oxides, Microstructure, Nickel, Nickel oxide, Nuclear energy, Nuclear fuels, Redox reactions, Scanning electron microscopy, Transmission electron microscopy, Crack paths, Dissolution rates, Iron cations, Nickel chromium, Redox potentials, Residual oxides, Rock-salt structure, Oxide films
National Category
Natural Sciences
Identifiers
URN: urn:nbn:se:ri:diva-34548DOI: 10.1007/978-3-319-68454-3_33Scopus ID: 2-s2.0-85042437045ISBN: 9783319684536 (print)OAI: oai:DiVA.org:ri-34548DiVA, id: diva2:1237554
Conference
EDM 2017: Proceedings of the 18th International Conference on Environmental Degradation of Materials in Nuclear Power Systems – Water Reactors.
2018-08-092018-08-092018-08-09Bibliographically approved