| About this Abstract |
| Meeting |
2021 TMS Annual Meeting & Exhibition
|
| Symposium
|
Frontiers in Solidification Science VIII
|
| Presentation Title |
Phase-field Simulations of the Lamella-to-rod Transition in Eutectic Solidification |
| Author(s) |
Mathis O. Plapp, Sabine Bottin-Rousseau, Silvère Akamatsu |
| On-Site Speaker (Planned) |
Mathis O. Plapp |
| Abstract Scope |
It is well known that the two most frequently observed microstructures for directionally solidified eutectic composites are lamellae and rods. Recently, it was observed in microgravity experiments that a rod state can be progressively replaced by lamellae that grow normal to a sample wall. We investigate the conditions for the occurrence of this phenomenon with
the help of three-dimensional phase-field simulations and find that
(i) a transverse temperature gradient is necessary, (ii) the lamellae can grow only if the volume fraction of the minority phase is above a critical value, (iii) this critical value depends on the solidification rate, and (iv) the resulting fronts are typically strongly heterogeneous, with lamellae and
rods coexisting in many different geometries. It was observed in previous simulations that the instability leading from lamellae to rods is propagative
in nature. This instability is quantitatively studied. |
| Proceedings Inclusion? |
Planned: |