|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Computational Materials Engineering for Nuclear Reactor Applications
||Cluster Dynamics Modeling of Extended Defects in Irradiated UO2 with Off-stoichiometry Considerations
||Sarah Khalil, Todd Allen, Anter El-Azab
|On-Site Speaker (Planned)
A novel Cluster Dynamics model that describes the nucleation and evolution of defect clusters in oxide systems has been developed. The model reproduces well a range of experimental data on nucleation and growth behavior and its temperature dependence. An important of the model is its ability to predict the off-stoichiometry of defect clusters allowing in turn the tracking of off-stoichiometry of the matrix. The effect of irradiation conditions such as irradiation temperature, irradiation dose and dose rate on clusters concentration and composition has been investigated. The preliminary results show that Frenkel defects dominate the nucleation process in irradiated UO2. Vacancy clusters tend to grow mainly by absorbing oxygen vacancies and the migration energy of uranium vacancies is the rate limiting energy in nucleation and growth of voids. The results also show that, in a stoichiometric UO2 under irradiation, vacancy clusters (voids) tend to have both hypo- and hyper-stoichiometric composition.
||Planned: A print-only volume