A molecular dynamics study of radiation induced diffusion in uranium dioxideFunded under: FP7-EURATOM
The nuclear oxide fuels are submitted 'in-pile' to strong structural and chemical modifications due to the fissions and temperature. The diffusion of species is notably the result of a thermal activation and of radiation induced diffusion. This study proposes to estimate to what extent the radiation induced diffusion contributes to the diffusion of lattice atoms in UO(2). Irradiations are simulated using molecular dynamics simulation by displacement cascades induced by uranium primary knock-on atoms between 1 and 80 keV. As atoms are easier to displace when their vibration amplitude increases, the temperature range which have been investigated is 300-1400 K. Cascade overlaps were also simulated. The material is shown to melt at the end of cascades, yielding a reduced threshold energy displacement. The nuclear contribution to the radiation induced diffusion is compared to thermally activated diffusion under in-reactor and long-term storage conditions.
Bibliographic Reference: An oral paper given at: E-MRS 2008 Spring Meeting Organised by: European Science Foundation Held at: Congress Center, Strasbourg (FR)
Availability: This article can be accessed online by subscribers, and can be ordered online by non-subscribers, at: http://dx.doi.org/doi:10.1016/j.jnucmat.2008.12.010
Record Number: 200910324 / Last updated on: 2009-09-22
Original language: en
Available languages: en