Ahmed Kaci BOUKELLAL : Numerical study of solidification in a pure material and in a binary alloy using the phase-field method

Résumé :
The phase-field method has emerged as powerful tool to study quantitatively the solidification of pure materials and binary alloys over the last two decades. In the present work, it was implemented, on one hand to study the Si isothermal solidification, focusing on the suitable choice of the anisotropy functions at the solid-liquid interface that allow to reproduce the equilibrium and growth experimental shapes. On the other hand, to investigate the grain-boundaries dynamics during directional solidification of Mg-Gd alloys, emphasizing the importance of the thermal gradient on the selection mechanism during the columnar growth of a polycrystalline hcp material. Some open questions on the phase-field modeling of solidification, like rapid solidification problems, will be adressed.