|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||GAT-2017 (Gamma Alloys Technology - 2017)
||F-45: Fine Structure of Ordinary Dislocation Dipoles and their Evolution in Deformed Gamma-TiAl via Atomistic Simulations
||Yan He, Zhao Liu, Hao Wang, Dongsheng Xu, Rui Yang
|On-Site Speaker (Planned)
In intermetallic gamma-TiAl, dislocation dipoles in the form of faulted dipoles are frequently encountered in deformed samples, but their fine structure and transformation into point defects remain largely undocumented. In this work, narrow dipoles in gamma-TiAl are systematically investigated with atomistic simulations. Their configurations are unraveled by interatomic potentials, which indicates the stability of faulted dipoles over other forms. The results are compared with experimental observations. Molecular dynamics simulations indicate that at elevated temperature, dipoles transform into individual defects, e.g., vacancy clusters, stacking fault tetrahedra and interstitial loops, depending on dipole height and orientation. Via metadynamics methods, activation energies of the atomic processes therein are obtained and the lifetime of the deformation debris is estimated, which shows their stability on the experimental timescale. The influence of stable narrow dipoles on plastic deformation is discussed.
||Planned: Stand-alone book in which only your symposium’s papers would appear (indicate title in comments section below)