|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Computational Materials Science and Engineering for Nuclear Energy
||Interstitial-mediated Diffusion and Aggregation Mechanism for Transmutation Elements Rhenium and Ormium Precipitation in Tungsten
||Guanghong Lu, Hongbo Zhou, Yuhao Li
|On-Site Speaker (Planned)
Tungsten (W) is considered as the most promising candidates for plasma facing material in future fusion reactor. However, 14 MeV high energy neutrons under a fusion environment will produce the transmutation elements. Rhenium (Re) and Osmium (Os) as the major transmutation production in W will precipitate under irradiation, leading to significant effects on the microstructure and mechanical properties of materials. With the first-principles method in combination with thermodynamic models, self-interstitial atom (SIA) is shown to be easily trapped by Re/Os once overcoming a low energy barrier, forming a W-Re/Os complex dumbbell. Such W-Re/Os dumbbell forms a high stable Re-Re/Os-Os dumbbell structure with the substitutional Re/Os atoms, which can serve as trapping centre for subsequent interstitial-Re/Os, leading to the growth of Re/Os-rich clusters. Our finding suggests an interstitial-mediated mechanism for the irradiation-induced Re/Os clustering in W.
||Planned: Supplemental Proceedings volume