Impact of lithium accommodation on defect chemistry in ZrO₂

Gareth F. Stephens1

Yan Ren Than3, William Neilson2, Lee J. Evitts1, Mark R Wenman3, Samuel Murphy2, Robin W. Grimes3, Aidan Cole-Baker4, Susan Ortner5, Natasha Gotham5, Michael J.D. Rushton1, William E. Lee1, Simon C. Middleburgh1

1Bangor University;

2Lancaster University;

3 Imperial College London;

4 Jacobs Ltd.;

5 National Nuclear Laboratory.

Abstract

Identifying the mechanism by which Li accelerates zirconium alloy corrosion will allow new alloying additions to be considered and new water chemistry regimes to be investigated, improving the efficiency and performance of future nuclear power reactors, reducing the cost of operation and design.
Density functional theory (DFT) was used to identify the most stable accommodation mechanisms for Li in ZrO2 at an atomic scale through the binding properties of valance electrons. A Brouwer diagram has been developed that predicts the nature of the defect structures and their competing species concentrations. This was then combined with experimental data to corroborate the most stable accommodation mechanisms of Li in ZrO2. The solubility of Li in bulk ZrO2 is predicted to be low indicating that accelerated corrosion due to bulk Li accommodation is unlikely.

Event Timeslots (1)

Thursday – 16th September 2021
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Gareth F. Stephens