In situ investigation of the oxidation of Zr–Nb–Cu alloy in high-temperature hydrogenated water

• Published in: Corrosion science 2017-05, Vol.119, p.91-101
• Main Authors: Kim, Taeho, Kim, Seunghyun, Lee, Chung-yong, Mok, Yong-kyoon, Kim, Ji Hyun
• Format: Article
• Language: English
• Subjects: A. Alloy; A. Zirconium; B. Raman spectroscopy; B. TEM; C. Oxidation; Copper base alloys; Corrosion inhibitors; High temperature physics; Hydrogen storage; Niobium; Oxidation; Phase transitions; Precipitates; Raman spectroscopy; Studies; Tin base alloys; Transmission electron microscopy; Zirconium alloys; Zirconium base alloys
• ISSN: 0010-938X; 1879-0496
• DOI: 10.1016/j.corsci.2017.01.013

[Display omitted] •The oxide characteristics of Zr–Nb–Cu and Zr–Nb–Sn alloys were compared.•The Nb precipitates were positioned at the oxide/metal interface of Zr–Nb–Cu alloy.•The corrosion resistance of Zr–Nb–Cu alloy was higher than that of Zr–Nb–Sn alloy.•Dissolved hydrogen concentration was varied to see the effect on the phase formation.•Dissolved hydrogen concentration influenced the early-stage oxide phase formation. The oxidation behavior of a Zr–Nb–Cu alloy under high-temperature water conditions, with different dissolved hydrogen concentrations, was investigated using in situ Raman spectroscopy. The results were subsequently compared to those of ex situ TEM analyses. Upon decreasing the dissolved hydrogen concentration from 4.15 to 2.49mg/kg at STP, the peak intensity of tetragonal phase oxide weakened, while that of monoclinic oxide strengthened due to the phase transformation. Ex situ analyses revealed that the Zr–Nb–Cu alloy was oxidized slowly as compared to the Zr–Nb–Sn alloy due to the number of β-Nb precipitates in the oxide.