The critical dynamics of dislocation avalanches in plastic flow was examined using a phase field crystal model. In the model, dislocations were naturally created, without any ad hoc creation rules, by applying a shearing force to the perfectly periodic ground state. These dislocations diffuse, interact and annihilate with one another, forming avalanche events. By data collapsing the event energy probability density function for different shearing rates, a connection to interface de-pinning dynamics was confirmed. The relevant critical exponents agree with mean field theory predictions.

Plasticity and Dislocation Dynamics in a Phase Field Crystal Model. P.Y.Chan, G.Tsekenis, J.Dantzig, K.A.Dahmen, N.Goldenfeld: Physical Review Letters, 2010, 105[1], 015502