SHAPE OF GRAIN BOUNDARY GROOVE ONPURE ICE SURFACE

In this work we studied the evolution of the groove that forms the grain boundary (BG) when it emerges to a free surface, in the presence of different processes of matter transport. By using a confocal microscope, the shape of the grain edge groove was obtained in an ice sample with orientation< 1010 >/50◦ at −5◦C ; after keeping it 3 h in an environment with dry air. The shapes and depths of the grain boundary groove obtained experimentally, at regular time periods, were satisfactorily fitted considering a process of transport of matter developed by Srinivasan and Trivedi. In this model the transport of matter is mainly ruled by gaseous diffusion and not by surface diffusion.

SHAPE OF GRAIN BOUNDARY GROOVE ONPURE ICE SURFACE

In this work we studied the evolution of the groove that forms the grain boundary (BG) when it emerges to a free surface, in the presence of different processes of matter transport. By using a confocal microscope, the shape of the grain edge groove was obtained in an ice sample with orientation <1010>/50◦at −5◦C ; after keeping it 3 h in an environment with dry air. The shapes and depths of the grain boundary groove obtained experimentally, at regular time periods, were satisfactorily fitted considering a process of transport of matter developed by Srinivasan and Trivedi. In this model the transport of matter is mainly ruled by gaseous diffusion and not by surface diffusion.

Superficial self-diffusion coefficient in Ih-ICE

The evolution of the grain boundary groove in a bicrystalline ice sample was studied in this work. The groove is formed by the intersection of the grain boundary with the free surface. The bicrystalline ice sample had an arbitrary misorientation and was immersed in ultra-pure silicone oil at -5°C in order to avoid evaporation processes. Photographs of the groove were taken every 17 minutes for 100 hours with an optical microscope and the evolution of the groove was determined from these images. Through this study, it was possible to measure the coefficient of surface self-diffusion of the ice at -5°C.