About this Abstract |
Meeting |
2025 TMS Annual Meeting & Exhibition
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Symposium
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Neutron and X-ray Scattering in Materials Science and Engineering
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Presentation Title |
Time resolved synchrotron X-ray diffraction study of the structural and mechanical evolutions within a zirconium alloy oxidized at high temperature
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Author(s) |
Raphaėlle Guillou, Jean Luc Bechade, Dominique Thiaudičre, Adam Bouayoune, Jean Luc Grosseau Poussard, Panicaud Benoit, Le Saux Matthieu |
On-Site Speaker (Planned) |
Raphaėlle Guillou |
Abstract Scope |
Zirconium alloys can oxidize under steam at high temperatures (>700°C) in hypothetical accidental conditions in pressurized water reactors, strongly affecting their mechanical properties. This study examines the phases and stresses in the zirconia layer formed during the oxidation of Zircaloy-4 under a He/O2 mixture at 700°C, 800°C, and 900°C. In situ X-ray diffraction measurements at the SOLEIL synchrotron reveal that the zirconia contains monoclinic and tetragonal phases, with the proportion of tetragonal phase decreasing during oxidation. The tetragonal phase remaining after cooling is located by Raman spectroscopy. Both phases undergo compressive stresses perpendicular to the oxide layer growth direction, which depend on temperature and decrease during oxidation. A mechanical model is proposed to describe the evolution of these stresses, with different stress source and release possibilities. The model parameters are analyzed to discuss the mechanisms of viscoplastic flow in the oxide, with future perspectives provided at the end. |
Proceedings Inclusion? |
Planned: |
Keywords |
Characterization, High-Temperature Materials, Mechanical Properties |