|About this Abstract
||2023 TMS Annual Meeting & Exhibition
||Ceramic Materials for Nuclear Energy Research and Applications
||Hidden Defect Evolution Mechanism in ThO2 Revealed by Atomistic Modeling
||Chao Jiang, Lingfeng He, Cody A Dennett, Marat Khafizov, James Mann, David H Hurley
|On-Site Speaker (Planned)
Irradiation-generated point defect clusters can significantly impact the physical and mechanical properties of materials. However, direct experimental visualization of these small-scale defects via high-resolution scanning transmission electron microscopy remains a challenge. In this presentation, we employ thorium dioxide (ThO2) with the fluorite structure as a model system to demonstrate the synergetic usage of ab initio calculations and kinetic Monte Carlo simulations as a powerful tool for identifying small defect complexes in irradiated materials. In addition to providing quantitative insights into defect evolution in ThO2 under irradiation, this study reveals the unexpected role of bound anti-Schottky defect clusters in mediating defect transport. Remarkably, despite their short lifetime due to poor thermal stability against dissociation, the transient formation of bound anti-Schottky defects under irradiation and their subsequent migration represent the dominant mechanism behind the growth of large interstitial loops that have been experimentally observed in ThO2.
||Computational Materials Science & Engineering, Ceramics, Nuclear Materials