About this Abstract |
Meeting |
2021 TMS Annual Meeting & Exhibition
|
Symposium
|
Advanced Characterization Techniques for Quantifying and Modeling Deformation
|
Presentation Title |
On the Mechanistic Origins of Maximum Strength in Nanocrystalline Materials |
Author(s) |
Ankit Gupta, Gregory B. Thompson, Garritt J. Tucker |
On-Site Speaker (Planned) |
Ankit Gupta |
Abstract Scope |
Maximum strength in nanocrystalline (NC) metals/alloys has been suggested to occur at grain sizes in the NC regime, where the governing deformation mechanism transitions from dislocation plasticity to GB mediated deformation. However, this notion has never been confirmed, owing to the difficulty in asserting the contribution of different mechanisms to microstructural strain accommodation. In this study, the contribution of individual nanoscale mechanisms to the overall deformation of NC metals/alloys is calculated from atomistic simulations leveraging continuum-based kinematic metrics to compute mechanistic contributions to microstructural strain. By employing such a quantitative approach, it is shown that the realization of maximum strength in NC metals corresponds to a grain size regime where the operative nanoscale mechanisms transition between intergranular and intragranular mediated mechanisms. The results are discussed in terms of systems’ crystal structure (BCC/FCC), alloy type (binary/medium entropy), where twinning is abundant, and potential artifacts of atomistic simulations as high strain rate. |
Proceedings Inclusion? |
Planned: |