ICE SURFACE PROPERTIES ANALYZED THROUGH GRAIN BOUNDARY MIGRATION

NASELLO, OLGA BEATRIZ; DI PRINZIO, CARLOS LEONARDO

Newfoundland Canada

Congreso; PCI 2002 Physic and Chemistry of Ice 2002; 2002

Physic and Chemistry of Ice 2002

One of the factors influencing the movement of grain boundaries is the groove formed at the intersection between grain boundary (GB) and the free surface of the sample. The equations that describe this interaction show that it is possible to obtain values for the GB mobility and the surface diffusion coefficient by studying the GB movement, provided that the variation of GB energy with inclination is known. In the present work, GB movement under the influence of surface is studied for pure bicrystalline ice samples. The bicrystals used in the study presented a  crystalline misorientation, and different inclinations. They were annealed at –6 oC in a silicon oil bath. The results obtained were analysed using the GB movement equation with the Sun and Bauer configuration, driven by capillarity under the retarding effect produced by a diffusion-generated groove at the GB-surface intersection. In order to interpret the experimental results, the variation of GB energy with inclination was modeled using the associated Coincidence Site Lattice (CSL). It is shown that by studying the time evolution of the i intercession between GB and sample surface it is possible to find GB mobility and surface diffusion values with a dispersion of less than 40%.