About this Abstract |
Meeting |
5th International Congress on 3D Materials Science (3DMS 2021)
|
Symposium
|
5th International Congress on 3D Materials Science (3DMS 2021)
|
Presentation Title |
Microstructural Stability of a Three-phase Eutectic Examined via 4D X-ray Nano-tomography |
Author(s) |
George R. Lindemann, Viktor Nikitin, Vincent De Andrade, Marc De Graef, Ashwin J Shahani |
On-Site Speaker (Planned) |
George R. Lindemann |
Abstract Scope |
Multiphase materials often operate at elevated temperatures where coarsening may cause significant microstructural changes. Therefore, a thorough understanding of coarsening mechanisms in such materials is critical to accurately predict their behavior in-service. Here, we use 4D x-ray nano-tomography (three spatial dimensions and time) to investigate microstructure evolution of an Al-Ag2Al-Al2Cu three-phase eutectic alloy during isothermal annealing below the eutectic temperature. With the aid of a new, in situ furnace and an innovative total variation regularization reconstruction technique, we visualize the evolution of eutectic lamellae and identify two unique coarsening modes that occur in parallel for the two intermetallic phases. Ag2Al coarsens via 2D Ostwald ripening when the rod’s initial radius is greater than a critical value while Al2Cu evolves via 3D Ostwald ripening. We also consider the role of crystallographic anisotropy. Our efforts reveal the need to expand contemporary theories of eutectic coarsening to better describe multiphase and multicomponent systems. |
Proceedings Inclusion? |
Definite: Other |