Heterogeneous nucleation in crystallization: Impact of impurities and local melt inhomogeneity

Literature data on inoculation of metallic melts are analyzed. Ability of solid particles to facilitate heterogeneous nucleation is explained by impurity adsorption, stabilizing flat facets on inoculant particles. A new concept of initiating heterogeneous nucleation, premised on chemical inhomogeneity of melt in the vicinity of solid particles, is proposed. It is supposed that ordering in liquid phase structure in the vicinity of solid-liquid interface favors formation of crystallization nuclei.