The use of micro-Raman imaging to measure 18O tracer distribution in thermally grown zirconia scales. (September 2015)

• Record Type: Journal Article
• Authors: Guerain, M.; Mermoux, M.; Duriez, C.
• Is Part Of: Corrosion science. Volume 98(2015)
• Page Start: 140
• Page End: 149
• Publication Date: 2015-09
• Subjects: A. Zirconium -- B. Raman spectroscopy -- C. High temperature corrosion; Corrosion and anti-corrosives -- Periodicals; 620.11223
• DOI: 10.1016/j.corsci.2015.05.020
• Languages: English
• ISSNs: 0010-938X

Abstract

Highlights: High temperature oxidation of Zircaloy-4 was studied by coupling 18 O diffusion and Raman imaging. Shifts of the monoclinic ZrO2 Raman lines versus the 18 O content were calibrated. 18 O diffusion profiles were obtained through micro-Raman scanning. Protective influence of a pre-transient corrosion scale has been investigated. Abstract: High temperature Zircaloy-4 oxidation has been studied through two-stage oxidation experiments using 18 O isotope. 18 O distribution in the oxidation scales was investigated by micro-Raman imaging. First, zirconia standards with known 18 O content were prepared and analyzed for calibration purposes. Then, to assess the method on a simple case, 18 O tracer penetration patterns were recorded after a 800 °C two-stage oxidation. Finally, oxidation at 850 °C of a Zircaloy4 cladding tube pre-corroded at 425 °C to simulate corrosion during normal reactor operation was studied. These preliminary results give insights on the protective nature of the first formed zirconia scale in case of an accident.