|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Computational Materials Engineering for Nuclear Reactor Applications
||Molecular Dynamics Simulations on Homogeneous Hydride Nucleation in Alpha-Zr
||Yongfeng Zhang, Xianming Bai, Jianguo Yu, Michael Tonks
|On-Site Speaker (Planned)
A nucleation pathway for homogeneous gamma-hydride formation in alpha-Zr is proposed based on molecular dynamic simulations with the charge-optimized-many-body potential. The solution energy of H in alpha-Zr increases with increasing H concentration. At high concentration, H atoms precipitate into planar configuration, resulting in the coherent zeta-phase which has much lower energy than random solution at the same concentration. Shearing of the zeta-phase by 1/3< 10-10 > partials in the basal plane leads to the formation of the zeta-fct phase, which can further grow into the gamma-hydride. The hcp-fcc transformation in the zeta-phase is favored thermodynamically with negligible barrier. Furthermore, three alternative shear partials are identified during the transformation. This new mechanism involves much less shear strain accumulation in the Zr matrix than that estimated in previous theory.
||Planned: A print-only volume