| About this Abstract |
| Meeting |
2020 TMS Annual Meeting & Exhibition
|
| Symposium
|
Deformation and Transitions at Grain Boundaries VII
|
| Presentation Title |
G-9: Deformation Nanomechanics and Dislocation Quantification at Atomic Scale in Nanocrystalline Pure-metal Magnesium |
| Author(s) |
Md Shahrier Hasan, Wenwu Xu |
| On-Site Speaker (Planned) |
Md Shahrier Hasan |
| Abstract Scope |
Classical Molecular Dynamic Simulation method is used for uni-axial tensile deformation of nanocrystalline magnesium of varied mean grain size from 6 nm to 45 nm. The deformation nano-mechanics reveals two distinct deformation mechanism. For larger grain size, conventional dislocation dominated deformation is observed while for smaller grain size, predominantly grain boundary atoms participate in the deformation process where different grain boundary-based mechanism is observed such as grain boundary sliding, grain boundary rotation etc. Dislocation quantification further supports this observation and shows that the change in dislocation density in the sample drastically reduces with decreasing grain size particularly at the yield point where new dislocation nucleation occurs by deformation. A comparative analysis of the grain size dependent mechanical properties reveals a gradual transition from grain boundary dominated stress-strain curve profile to dislocation dominated stress-strain curve profile as the grain size of the sample is increased from 6 nm to 45 nm. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |