Microstructural analysis of preformed oxides on a zirconium alloy before and after subsequent oxidation at 1000–1200 °C

• Published in: Corrosion science 2018-07, Vol.139, p.410-420
• Main Authors: Lee, Cheol Min, Jeong, Hu Young, Yoon, Aram, Mok, Yong-Kyoon, Sohn, Dong-Seong
• Format: Article
• Language: English
• Subjects: A. Alloy; A. Zirconium; B. TEM; C. High temperature corrosion; C. Oxide coatings; Corrosion; Microstructural analysis; Microstructure; Oxidation; Oxidation resistance; Precipitates; Twin boundaries; Zirconium alloys; Zirconium base alloys; Zirconium oxides
• ISSN: 0010-938X; 1879-0496
• DOI: 10.1016/j.corsci.2018.05.022

[Display omitted] •Microstructures of preformed oxides on a zirconium alloy were analysed by TEM.•Zr-Sn type precipitates were not observed after subsequent oxidation.•Many voids were formed after subsequent oxidation.•Many intergranular cracks were formed after subsequent oxidation at 1200 °C. Zr-1Nb-1Sn-0.1Fe alloy was pre-oxidised at 1200 °C and subsequently oxidised at 1012, 1100, and 1200 °C. The preformed oxide enhanced the oxidation resistance at 1012 and 1100 °C, but not at 1200 °C. The microstructures of the preformed oxides subsequently oxidised at 1200 °C were compared with those of the preformed oxides subsequently oxidised at 1012 and 1100 °C. The preformed oxide probably contained more intergranular cracks and liquid Sn precipitates, and less twin boundaries during the subsequent oxidation at 1200 °C. These microstructural differences may have caused the preformed oxide not to enhance the oxidation resistance at 1200 °C.