Hydrodynamic theory of freezing: nucleation and polycrystalline growth
journal contributionposted on 2017-11-03, 09:53 authored by Frigyes Podmaniczky, Gyula TothGyula Toth, Gyorgy Tegze, Laszlo Granasy
Structural aspects of crystal nucleation in undercooled liquids are explored using a nonlinear hydrodynamic theory of crystallization proposed recently [G. I. Toth et al., J. Phys.: Condens. Matter 26, 055001 (2014)], which is based on combining fluctuating hydrodynamics with the phase-field crystal theory. We show that in this hydrodynamic approach not only homogeneous and heterogeneous nucleation processes are accessible, but also growth front nucleation, which leads to the formation of new (differently oriented) grains at the solid-liquid front in highly undercooled systems. Formation of dislocations at the solid-liquid interface and interference of density waves ahead of the crystallization front are responsible for the appearance of the new orientations at the growth front that lead to spherulite-like nanostructures.
This work has been supported by NKFIH, Hungary under contract No OTKA-K-115959, by the ESA MAP/PECS projects MAGNEPHAS III (Contract No 40000110756/11/NL/KML) and GRADECET (Contract No 40000110759/11/NL/KML). G. Tegze is a grantee of the Janos Bolyai Scholarship of the MTA, Hungary.
- Mathematical Sciences