  The critical dynamics of dislocation avalanches in plastic flow is examined
using a phase field crystal (PFC) model. In the model, dislocations are
naturally created, without any \textit{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 depinning dynamics is confirmed. The
relevant critical exponents agree with mean field theory predictions.
