| About this Abstract |
| Meeting |
2020 TMS Annual Meeting & Exhibition
|
| Symposium
|
Radiation Effects in Metals and Ceramics
|
| Presentation Title |
Elucidating Atomistic Mechanisms for Interface- and Grain Boundary-mediated Radiation Defects Annihilation |
| Author(s) |
Penghui Cao, Miaomiao Jin, Kangpyo So, Ju Li, Michael Short |
| On-Site Speaker (Planned) |
Penghui Cao |
| Abstract Scope |
Effective and efficient removal of defects is of crucial importance to design radiation damage-tolerant materials. Here, atomistic simulations and in-situ irradiation transmission electron microscopy experiments of nanocrystalline Cu and carbon nanotube (CNT)-Al composite reveal the atomic details of defect nucleation and migration, and the mechanisms for the annihilation of defect clusters during irradiation. For nanocrystalline Cu, stacking fault tetrahedra formed due to radiation damage cascades show preferential migration to irradiated grain boundary. Interstitial-loaded grain boundaries are observed to be dynamically resilient, and persistently interact with the stacking fault tetrahedra, revealing a self-healing response to radiation damage. For CNT-Al composite, experiments and atomistic simulations together reveal the dynamic evolution and convergent diffusion of radiation-induced defects to CNTs, facilitating defect recombination and enhancing radiation tolerance. The occurrence of CNT-biased defect convergent migration is tuned by the thermodynamic driving force of stress gradient in Al matrix due to the CNT phase transformation. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |