Geometrically necessary dislocations and strain-gradient plasticity: a few critical issues
نویسندگان
چکیده
منابع مشابه
Finite element analysis of geometrically necessary dislocations in crystal plasticity
We present a finite element method for the analysis of ductile crystals whose energy depends on the density of geometrically necessary dislocations (GNDs). We specifically focus on models in which the energy of the GNDs is assumed to be proportional to the total variation of the slip strains. In particular, the GND energy is homogeneous of degree one in the slip strains. Such models indeed aris...
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*Correspondence: [email protected] 1Materials Science and Engineering Department, University of California Los Angeles, Los Angeles, California, USA 2Mechanical and Aerospace Engineering Department, University of California Los Angeles, Los Angeles, California, USA Abstract The standard way of modeling plasticity in polycrystals is by using the crystal plasticity model for single crystals in eac...
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The role of geometrically necessary dislocations in providing macroscopic strengthening is reviewed with particle reinforcement as an example. The general relation between the Nye tensor and slip along a curvilinear slip line net is derived to emphasise the importance of curvature of slip lines upon the rate of dislocation storage. 2002 Acta Materialia Inc. Published by Elsevier Science Ltd. Al...
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ژورنال
عنوان ژورنال: Scripta Materialia
سال: 2003
ISSN: 1359-6462
DOI: 10.1016/s1359-6462(02)00335-4