| About this Abstract |
| Meeting |
2023 TMS Annual Meeting & Exhibition
|
| Symposium
|
Frontiers in Solidification: An MPMD Symposium Honoring Jonathan A. Dantzig
|
| Presentation Title |
Growth Competition between Columnar Dendritic Grains under Additive Manufacturing Conditions |
| Author(s) |
Elaheh Dorari, Kaihua Ji, Adriana Eres Castellanos, Alec Saville, Oliver Hesmondhalgh, Joe McKeown, Amy J. Clarke, Alain Karma |
| On-Site Speaker (Planned) |
Elaheh Dorari |
| Abstract Scope |
A comprehensive understanding of the growth competition between columnar dendritic grains at high solidification rates is critically important for emerging technologies like additive manufacturing (AM). While this growth competition has been investigated extensively under conventional slow solidification conditions, it remains comparatively less explored at high growth rates. We present a combined experimental and computational study of microstructure and grain structure evolution in thin-films of Al-Si alloys solidified under AM conditions. This evolution is characterized using in situ Dynamic Transmission Electron Microscopy (DTEM) observation of solid-liquid interface dynamics together with post-mortem crystallographic mapping of columnar grain structures. The experimental results are interpreted using a new quantitative phase-field formulation of rapid binary alloy solidification that incorporates quantitively nonequilibrium effects at the solid-liquid interface. The experimental and phase-field simulations results are used to construct grain-boundary orientation selection maps, which highlight similarities and differences between grain selection mechanisms at slow and rapid solidification rates. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Additive Manufacturing, Characterization, Solidification |