Statistically Stored Dislocations in Rate-independent Plasticity

نویسنده

  • P. Cermelli
چکیده

Work hardening in crystalline materials is related to the accumulation of statistically stored dislocations in low-energy structures. We present here a model which includes dislocation dynamics in the rate-independent setting for plasticity. Three basic physical features are taken into account: (i) the role of dislocation densities in hardening; (ii) the relations between the slip velocities and the mobility of gliding dislocations; (iii)the energetics of self and mutual interactions between dislocations. The model unifies a number of different approaches to the problem presented in literature. Reaction-diffusion equation with mobility depending on the slip velocities are obtained for the evolution of the dislocations responsible of hardening.

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تاریخ انتشار 2000