Pt catalytic effects on the corrosion and hydrogen chemisorption properties of Zircaloy-2

JOURNAL OF NUCLEAR MATERIALS

卷:544

Article

Rowthu, Sriharitha^1,2  Grundler, Pascal V.¹  Mueller, Elisabeth¹  Ritter, Stefan¹ 

[1] Paul Scherrer Inst PSI, CH-5232 Villigen, Switzerland

[2] Indian Inst Technol IIT Gandhinagar, Mat Engn, Gandhinagar 382355, Gujarat, India

关键词: Platinum catalysts;    boiling water reactor (BWR);    Zircaloy-2;    corrosion mechanisms;    hydrogen absorption;   

DOI  :  10.1016/j.jnucmat.2020.152716

来源: Elsevier

【 摘 要 】

Noble metals are added to boiling water reactors (BWRs) to mitigate stress corrosion cracking of structural components made from steels and Ni-based alloys and this technology is referred to as Noble Metal Chemical Addition (NMCA) or NobleChem (TM). There is a growing concern that NMCA can cause unwanted harmful effects on the corrosion and hydrogen uptake properties of Zircaloy-2 fuel cladding. To investigate this, we have subjected Zircaloy-2 fuel claddings to out-of-pile BWR conditions in a custom-built autoclave. These claddings are oxidized in pressurized hot water (280 degrees C, 9 MPa) for 25, 60 and 150 days, wherein Pt nanoparticles (similar to 10 nm) were simultaneously injected. Cross-sectional focused ion beam cuts made at the oxide-metal interface reveal that the oxide growth is not significantly influenced by the local Pt loadings (<= 1 mu g cm(-2)). Surprisingly, an inverse correlation was observed between oxide thicknesses and metal's hydrogen contents. Interestingly, Pt catalysts have led to diminished hydrogen absorption in specimens with liner exposed to the hot water. Overall, Pt catalysts exhibited no detrimental effects on the corrosion rate and hydrogen absorption in Zircaloy-2. (C) 2020 The Author(s). Published by Elsevier B.V.

【 授权许可】

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