About molybdenum behaviour during U(Mo)/Al(Si) interaction processes

• Published in: Journal of nuclear materials 2013-02, Vol.433 (1-3), p.255-264
• Main Authors: Iltis, X., Allenou, J., Verhaeghe, B., Palancher, H., Tougait, O., Bonnin, A., Tucoulou, R.
• Format: Article
• Language: English
• Subjects: Applied sciences; Chemical Sciences; Controled nuclear fusion plants; Correlation; Depletion; Diffraction; Diffusion; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Fission nuclear power plants; Fuels; Installations for energy generation and conversion: thermal and electrical energy; Material chemistry; Molybdenum; Nuclear fuels; Silicon; Tomography
• ISSN: 0022-3115; 1873-4820
• DOI: 10.1016/j.jnucmat.2012.09.028

U(Mo)/Al(Si) diffusion couples are studied to provide a better understanding of the interaction processes between the U(Mo) fuel and the Al(Si) matrix and, more specifically, to determine the molybdenum behaviour in the interaction product, close to the U(Mo) alloy. Micro-computed tomography and micro-X-ray diffraction measurements in transmission mode, coupled with scanning transmission electron microscopy and energy dispersive X-ray spectroscopy analysis show that molybdenum is present in the interaction layer, close to the U(Mo) interface, in an U4Mo(MoxSi1−x)Si2 ternary intermediate phase, mixed with the U3Si5 phase. The formation of this Mo-containing phase is accompanied by a Mo depletion process, in the underlying U(Mo) alloy, this depletion leading to a γ-U(Mo) phase local destabilisation. A strong correlation between the Si and the Mo behaviours, in the U(Mo)/Al(Si) system, is thus evidenced.