Формирование структуры металлов и сплавов в условиях энергетической неоднородности поверхности раздела фаз при периодической кристаллизации

The paper considers the formation of the structure of metals and alloys in the case of a periodic crystallization. It is assumed that the transition of atoms from the liquid phase to the solid phase can happen in the thickness of one atomic layer. Such a transition is considered to be is energetically costly. A model of the atomic smooth surface has a kink. In the case of diffuse phase boundaries between phases suggest that the solid surface is sufficiently energetically favorable locations for attachment of the atoms of the liquid phase. Then the phase boundary moves into the liquid phase continuously. In the presented model does not take into account the electronic structure of the phase boundaries. This reduces the possibility of a correct description of the crystallization process. Analysis of the phase portrait of the crystallization process shows that there solidifying metal centers with a minimum of free energy. The coincidence of crystallite interaxial distance with crystallite growth period suggests that these points may be centers of crystallization for the directionally solidified castings or welded joints.