| About this Abstract |
| Meeting |
2021 TMS Annual Meeting & Exhibition
|
| Symposium
|
Frontiers in Solidification Science VIII
|
| Presentation Title |
Coexistence of Rod-like and Lamellar Eutectic Growth Patterns: In Situ Experiments in Microgravity |
| Author(s) |
Silvere Akamatsu, Sabine Bottin-Rousseau, Mathis Plapp, Victor Witusiewicz, Ulrike Hecht |
| On-Site Speaker (Planned) |
Silvere Akamatsu |
| Abstract Scope |
We present real-time observations of a lamellar-to-rod transition during directional solidification of a model transparent eutectic alloy. In order to avoid thermosolutal convection in the liquid, in situ experiments –the first of their kind– were carried out under microgravity onboard the ISS (ESA/NASA project TRANSPARENT ALLOYS). Previous studies (on ground) brought important results on the dynamics of lamellar and rod-like eutectic patterns in separate systems. Here, we discovered a way, based on the use of a transverse temperature gradient, to maintain a coexistence between extended rod-like and lamellar domains over large time and space scales. The lamella/rod instability mode, the dynamics of the boundary between the two domains, and possible crystallographic effects will be discussed. We will compare our observations with previous ex situ observations in metallic ingots, and recent numerical simulations. This growth dynamics leads to the freezing of an interesting composite architecture in the bulk solid. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Solidification, Modeling and Simulation, Composites |