| About this Abstract |
| Meeting |
MS&T24: Materials Science & Technology
|
| Symposium
|
Corrosion and Environmental Degradation: Theory and Practice
|
| Presentation Title |
Dislocation Nano-Hydrides In Nickel: Energetics and Effects on the Plastic Deformation |
| Author(s) |
Fernando Daniel Leon-Cazares, Xiaowang Zhou, Chris San Marchi |
| On-Site Speaker (Planned) |
Fernando Daniel Leon-Cazares |
| Abstract Scope |
Hydrogen segregation to the core of dislocations has been suggested to promote the formation of nano-hydrides, which may impact dislocation mobility and lead to hydrogen embrittlement. However, the energy barriers for the nucleation of dislocation nano-hydrides and their effects on the plastic response remain open questions. The current study combines atomistic simulations and continuum line tension modeling to explore the energetics of Cottrell atmosphere and dislocation nano-hydride formation in the Ni-H model system. The analysis includes the effects of dislocation character and applied stresses, showing that these have a large effect on nano-hydride size and shape, stacking fault width and dislocation mobility. Hydrogen segregation to screw dislocations is further shown to increase the energy barriers to undergo constriction and cross-slip, with direct implications on slip localization. The results of this work provide a better understanding of the elusive dislocation nano-hydrides and their potential role on material degradation in hydrogen environments. |