| About this Abstract |
| Meeting |
MS&T21: Materials Science & Technology
|
| Symposium
|
Advanced Characterization of Materials for Nuclear, Radiation, and Extreme Environments
|
| Presentation Title |
Imaging Nanostructural Heterogeneities and Vacancy Supersaturation in Ni-20Cr after Corrosion in Molten Salt |
| Author(s) |
Yang Yang, Weiyue Zhou, Shen Yin, Sarah Wang, Qin Yu, Matthew J. Olszta, Daniel K. Schreiber, Jim Ciston, Robert O. Ritchie, Mark Asta, Ju Li, Michael P. Short, Andrew M. Minor |
| On-Site Speaker (Planned) |
Yang Yang |
| Abstract Scope |
Extreme environments (e.g., radiation damage and corrosion) can drive materials out of their equilibrium states, leading to the dynamical evolution of nanostructural heterogeneities. These processes include chemical segregation, void nucleation, and strain localization, etc. A fundamental understanding of how different kinds of heterogeneities develop and interact with each other is critical for the development of more damage-tolerant materials in harsh environments. However, the progress on this has been hindered by the difficulty of characterizing certain kinds of nanostructural heterogeneities. Here, using a correlative electron microscopy approach by combining focused-ion-beam lift out, three-dimensional (3D) electron tomography, and four-dimensional scanning transmission electron microscopy (4D-STEM), we report on the characterization of the nanostructural heterogeneities in Ni-20Cr alloy after molten-salt corrosion. We attempt to explain how defect transport near the grain boundaries induces void growth and how the void morphology is affected by the nonequilibrium point-defect concentrations and the local strain ‘hot spots'. |