The Effect of Anisotropy on the Equilibrium Morphology of a Crystal-melt Interfacial Grain Boundary Groove

摘要

The equilibrium morphology of a grain boundary groove at a crystal-melt interface under the constraint of a thermal gradient is computed. An integral undercooling approach is employed to compute uncoupled half-groove shapes. Coupled groove solutions are identified by minimum energy configurations. The orientation dependent interfacial energy is included in the determination of local interface temperature and in the coupling of adjacent grains comprising the groove. In contrast to the continuous set of solutions arising from the isotropic case, it is shown that a single solution exists for a fixed groove, given by a minimum in total energy which comprised both interfacial and volumetric contributions. Lateral groove migration and grain boundary tilting are also considered. Coupled groove solutions are computed for several tilt-boundary configurations, and the individual effects of grain orientation, grain boundary energy, and magnitude of anisotropy are investigated.