Dynamics of Faceted Grain Boundary Grooves
نویسندگان
چکیده
The dynamics of dislocation-free crystal facets is examined in the context of grain boundary grooves at the junction between two crystallites of a solid and the liquid phase. The geometry and thermal conditions of grain boundary grooves allow a detailed analysis of facet morphology during solidification in terms of the nucleation and spreading rates of elementary crystal planes. Observations on the freezing of water in a two-dimensional cell reveal several dynamical features which are treated by the theory. Additional observations provide indications for the stiffness and premelting of grain boundaries.
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