When a metal cools from its liquid state, part of the nucleation happens from pre-existing clusters (a group of unit cells of the crystal lattice) already present in the liquid.
In the case of a phase change from vapour directly to solid, on rapid cooling, is it possible for Aluminium (or some other metal) to exhibit a different crystal structure or worse, be completely amorphous? As I understand it, Aluminum atoms won't have the time to arrange themselves in FCC right?
When BMGs (Bulk Metallic Glasses) are formed by rapid solidification, there is no long range order, only short range order, which is because this is already present at the liquid phase. But in this scenario of rapid gas-to-solid transformation, would there be any order, long or short?
What sort of a microstructure would you get on bubbling Aluminium vapors through a large tank of Helium? Would it be a glassy microstructure and/or would you get nano-powders and/or a new crystal structure formation because of the excess helium which would be present in the Aluminium matrix?