About this Abstract |
Meeting |
2021 TMS Annual Meeting & Exhibition
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Symposium
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Heterostructured and Gradient Materials (HGM IV): Tailoring Heterogeneity for Superior Properties
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Presentation Title |
Yielding in a Metallic Nanocomposite at the Nanoscale |
Author(s) |
Kangpyo So, Myles Stapelberg, Yu Ren Zhou, Hideki Mori, Shigenobu Ogata, Michael Short, Ju Li, Sidney Yip |
On-Site Speaker (Planned) |
Kangpyo So |
Abstract Scope |
Yielding is an intriguing phenomenon which has intimate links with plasticity and fracture in materials. Understanding the microscopic nature of yielding allows designing materials with improved performance. Yet, fundamental yielding mechanisms have not been fully understood, especially in nanostructured metal composites. In this work, we propose a yielding mechanism of a nanofiber-filler metal-matrix nanocomposites. We uncover unit processes at the nanoscale during mechanical deformation and rupture of CNT-Al nanocomposite through in-situ TEM coupled with numerical analysis. Non-shearable CNTs provide a strong pinning point on dislocation glide or crossover, triggering high local shear strains which result in shear transformation deformation. Bridging of the notch tip by CNT hinders further penetration of notch, indicating substantial nanoscale load transfer. Further details from atom-scale simulations of CNT-induced hardening along with strain redistribution during deformation will be discussed. Our nanoscale observations and interpretations reveal the mechanistic nature of deformation in a complex, out-of-equilibrium materials system. |
Proceedings Inclusion? |
Planned: |
Keywords |
Aluminum, Composites, Characterization |