Thermal Effects in Dislocation Theory II: Shear Banding and Yielding Transitions
نویسنده
چکیده
The thermodynamic dislocation theory presented in preceding papers is used here to describe shear-banding instabilities. Central ingredients of the theory are a thermodynamically defined effective configurational temperature, and a formula for the plastic deformation rate determined by thermally activated depinning of entangled dislocations. An important feature of this paper is an interpretation of yielding transitions in polycrystalline solids.
منابع مشابه
Thermal effects in dislocation theory. II. Shear banding.
The thermodynamic dislocation theory presented in previous papers is used here to describe shear-banding instabilities. Central ingredients of the theory are a thermodynamically defined effective configurational temperature and a formula for the plastic strain rate determined by thermally activated depinning of entangled dislocations. This plastic strain rate is extremely sensitive to variation...
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