The drag effect of air bubbles on triple junction migration of pure ice

The migration of a grain triple junction was studied on ice pure samples with bubbles at -2°C for almost 3 h. This work studies the interaction between Grain Boundary (GB) and bubbles. The evolution of the triple junction was recorded from successive photographs obtained from a LEICA® optical microscope. Simultaneously, numerical simulations of grain triple junction with mobile bubbles were carried out using Monte Carlo method with the following conditions: The bubbles in the bulk were kept immobile and those in the GB were allowed to move. In addition, mobile bubbles were forced to stay inside the GB. The simulations show that bubbles slow down the movement of the GB and of the triple junction. What’s more, the simulated triple junction obtained fits very well the experimental triple junction geometry, and the GB diffusivity values obtained coincide with those measured experimentally at the same temperature and reported by other authors. Finally, the drag effect of the mobile bubbles on the GB migration was verified.