Role of density fluctuations in the relaxation of random dislocation systems
نویسندگان
چکیده
We study the relaxation dynamics of systems of straight, parallel crystal dislocations, starting from initially random and uncorrelated positions of the individual dislocations. A scaling model of the relaxation process is constructed by considering the gradual extinction of the initial density fluctuations present in the system. The model is validated by ensemble simulations of the discrete dynamics of dislocations. Convincing agreement is found for systems of edge dislocations in single slip irrespective of the net Burgers vector of the dislocation system. It is also demonstrated that the model does not work in multiple slip geometries. PACS numbers: 61.72.Lk, 05.40.-a, 45.50.Jf, 62.20.fq
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تاریخ انتشار 2008