| Recent advances we made recently in phase field modeling of polycrystalline solidification will be reviewed. Polycrystalline patterns are present in a broad variety of systems including metal alloys, polymers, minerals, and have biological relevance as well. The fact that similar polycrystalline patterns are observed in systems of very different nature implies that a minimal model based on coarse-grained fields, which neglects the details of molecular interactions, might be appropriate. We have developed a phase field models of polycrystalline solidification that rely on a quaternion representation of the crystallographic orientation, and incorporates several nucleation mechanisms including formation of new grains at the growth front. It has been applied for describing various polycrystalline structures including various dendritic morphologies, disordered dendrites, eutectic structures, various types of spherulites and composite structures. Finally, we present preliminary results for polycrystalline solidification in single-component and binary versions of the phase-field crystal approach. |
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