Breakaway oxidation of zirconium alloys exposed to steam around 1000 °C

Matthieu Le Saux (1, 2) , Jean-Christophe Brachet (2) , Valérie Vandenberghe (2) , Antoine Ambard (3) , Raphaël Chosson (4)

1 IRDL - Institut de Recherche Dupuy de Lôme
2 CEA-DES (ex-DEN) - CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire)
3 EDF R&D - EDF R&D
4 FRAMATOME

The breakaway oxidation of Zircaloy-4 and M5Framatome alloys oxidized in flowing steam around 1000 °C was studied. The influences of oxidation temperature between 950 and 1050 °C, one-side versus two-side oxidation and chemical variations around the nominal composition of M5Framatome were investigated. Breakaway oxidation is sensitive to the oxidation temperature, the material and the oxidation type. A phenomenological mechanism for breakaway oxidation is postulated on the basis of microstructural and microchemical analyses.

Keywords: LOCA; Zircaloy-4; M5 Framatome; Breakaway oxidation; High temperature

Domains: Physics [physics]; Condensed Matter [cond-mat]; Materials Science [cond-mat.mtrl-sci]; Engineering Sciences [physics]; Materials

Matthieu Le Saux, Jean-Christophe Brachet, Valérie Vandenberghe, Antoine Ambard, Raphaël Chosson. Breakaway oxidation of zirconium alloys exposed to steam around 1000 °C. Corrosion Science, 2020, 176 (108936), pp.1-21. ⟨10.1016/j.corsci.2020.108936⟩. ⟨hal-02924036⟩