About this Abstract |
Meeting |
MS&T24: Materials Science & Technology
|
Symposium
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Ceramic Materials for Nuclear Energy Systems
|
Presentation Title |
Cluster Dynamics Simulations of Tritium and Helium Diffusion in Lithium Ceramics |
Author(s) |
Ankit Roy, Michel Sassi, Krishna Pitike, Mark Lanza, Andrew Casella, David Senor, Christopher Matthews, David Andersson, Ram Devanathan |
On-Site Speaker (Planned) |
Ankit Roy |
Abstract Scope |
Tritium and Helium diffusion in LiAlO2 and LiAl5O8 phases influences the performance of tritium producing burnable absorber rods (TPBARs). Frenkel pair defects and clusters created by irradiation can attract T and He interstitials and form clusters of the type [He_i_x_Li], [He_i_x_Al], [He_i_xO],[Ti_x_Li], [T_i_x_Al] and T_i_x_O, 1≤x≤4 in a Li, Al or O vacancy site (notation denotes x He or T atoms in a 1 Li,1 Al or 1 O vacant site). Concentration and mobility of each of these clusters collectively contribute to diffusion of He and T gases in LiAlO2 and LiAl5O8. Here, free energy cluster dynamics simulations implemented in the Centipede code, are used to obtain concentration and diffusivities of these clusters which are then used to calculate total diffusivity of T and He gases in LiAlO2 and LiAl5O8. Results show that diffusivities of T and He are orders_of_magnitude higher in LiAlO2 as compared to that in LiAl5O8. |