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Driving Forces and Boundary Conditions in Continuum Dislocation Mechanics

Amit Acharya
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Abstract

As a guide to constitutive specification, driving forces for dislocation velocity and nucleation rates are derived for a field theory of dislocation mechanics. A condition of closure for the theory in the form of a boundary condition for dislocation density is also derived. Kinematical features of dislocation evolution like initiation of bowing of a pinned screw segment, and initiation of cross-slip of a screw segment are discussed. An exact solution for the expansion of a polygonal loop as well as representation within the theory of dislocation level Schmid and non-Schmid behavior, and unloaded stress-free and steady microstructures are also discussed.

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Amit Acharya. 2002-05-20. Driving Forces and Boundary Conditions in Continuum Dislocation Mechanics. https://arxiv.org/abs/cond-mat/0205402

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