2001/05/02 by M. -Carmen Miguel, Alessandro Vespignani, Stefano Zapperi +2
Physics and Astronomy · #cond-mat.stat-mech #cond-mat.mtrl-sci
published as Materials Science and Engineering 309-310, 324 (2001)
arxiv created 2001/05/02 · arxiv updated 2009/11/30
We propose a numerical model to study the viscoplastic deformation of ice single crystals. We consider long-range elastic interactions among dislocations, the possibility of mutual annihilation, and a multiplication mechanism representing the activation of Frank-Read sources due to dislocation pinning. The overdamped equations of motion for a collection of dislocations are integrated numerically using different externally applied stresses. Using this approach we analyze the avalanche-like rearrangements of dislocations during the dynamic evolution. We observe a power law distribution of avalanche sizes which we compare with acoustic emission experiments in ice single crystals under creep deformation. We emphasize the connections of our model with non-equilibrium phase transitions and critical phenomena.