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Plasticity and Dislocation Dynamics in a Phase Field Crystal Model

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 نشر من قبل Nigel Goldenfeld
 تاريخ النشر 2010
  مجال البحث فيزياء
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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.



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