The 9th International Conference on Multiscale Materials Modeling

講演情報

Symposium

C. Crystal Plasticity: From Electrons to Dislocation Microstructure

[SY-C7] Symposium C-7

2018年10月31日(水) 14:00 〜 15:30 Room1

Chair: David Rodney(Institut Lumiere Matiere, Universite Lyon 1, France)

[SY-C7] Uranium plastic deformation: A multiscale approach

Pavel A. Pokatashkin, Denis K. Ilnitsky, Alexei V. Yanilkin (Dukhov Research Institute of Automatics (VNIIA), Russia)

Uranium is a key element in nuclear technology. We focus on studying plastic deformation of the high-temperature BCC phase. On the one hand, classical molecular dynamics is used for obtaining material parameters, necessary for dislocation dynamics. Dislocation motion involves various mechanisms. The significance of their contribution to plastic response is studied on the other hand.

We show dislocation climb can be observed at nanosecond timescale. Imposing external shear results in gliding of the dislocation, making dislocation climb even more significant. Studying of those mechanisms is performed and quantitative parameters e.g. phonon drag coefficient, activation energy, activation volume are obtained. We emphasize that qualitative results remain the same for all three interatomic potentials considered in our study. Both discrete and continuum dislocation dynamics simulations are performed based on the results obtained from atomistic simulations. Synergy between two approaches of multiscale modeling results in better understanding of uranium plastic deformation.