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

• Published in: Corrosion science Vol. 176; no. 108936; pp. 108936 - 21
• Main Authors: Le Saux, Matthieu, Brachet, Jean-Christophe, Vandenberghe, Valérie, Ambard, Antoine, Chosson, Raphaël
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Ltd 01.11.2020; Elsevier BV; Elsevier
• Subjects: Breakaway oxidation; Condensed Matter; Engineering Sciences; High temperature; LOCA; M5Framatome; Materials; Materials Science; Oxidation; Physics; Zircaloy-4; Zircaloys (trademark); Zirconium alloys; Zirconium base alloys; M5Framatome; Zircaloy-4; LOCA; High temperature; Breakaway oxidation; M5 Framatome
• ISSN: 0010-938X; 1879-0496
• DOI: 10.1016/j.corsci.2020.108936

•Strong effect of oxidation temperature around 1000 °C on breakaway oxidation.•No significant effect of small chemical variations around nominal composition of M5Framatome.•Effect of one-side versus two-side oxidation in some cases.•Large hydrogen pickup fraction after the onset of breakaway oxidation.•Microstructural and microchemical specific features associated with breakaway oxidation. 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.