|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Ultrafine Grained Materials IX
||Effects of Stacking Fault Energy on Dislocation Nucleation and Plastic Deformation Mechanisms in fcc Metals
||Valery Borovikov, Mikhail I. Mendelev, Alexander H. King
|On-Site Speaker (Planned)
A series of EAM potentials were developed to study the effects of stable and unstable stacking fault energies (SFE and USFE, respectively) on the plastic deformation. The potentials lead to almost identical materials properties except of the SFE and USFE. Molecular dynamics simulations demonstrated that the yield stress (required for the dislocation nucleation) depends linearly on both SFE and USFE. The same potentials were also employed to study the effect of SFE on the plastic deformation in nanotwinned fcc metals. The simulation cell included several grain and twin boundaries. It was found that the yield strength and microstructural stability do not vary monotonically with SFE, but rather fall into two distinct cases corresponding to “low” and “high” SFEs. The first case is characterized by slip propagation by partial dislocations while in the second case, the slip propagation is realized via complete dislocations and the coherent twin boundary migration was observed.