C. L. Di Prinzio

Anisotropic migration of two-dimensional grain boundaries

Abstract Grain boundary migration in two-dimensional samples, when the capillary driving force depends on the grain boundary inclination, is studied. The grain boundary motion equation and the solutions to this equation, specially for samples with the initial geometry proposed by Sun and Bauer, are presented. It is shown that grain boundary velocities depend not only on the free surface energy but also on the second derivative of this energy with the grain boundary inclination. By using a very simple expression for the free surface energy, it is shown that small grain boundary anisotropies can cause important variations in grain boundary velocities.

An experimental method to study grain boundary diffusivity in anisotropic materials

It has been shown that the theoretical treatment developed by Di Prinzio et al. to study the grain boundary diffusivity in anisotropic material can be experimentally implemented. The method was applied to ice bicrystalline samples. The results obtained show that the diffusivity of tilt boundaries 〈1010〉/21 ° and 〈1010〉/90 ° depends on the grain boundary inclination. As a rule, the authors suggest that when Sun and Bauers method is followed to study grain boundary migration b and F(α) may always be determined; it should be kept in mind that, neither values of the Mγ(β) function nor the mean value of Mγ were obtained; instead Mγeff was found.