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arXiv · 2007.15355

A thermodynamically consistent theory of stress-gradient plasticity

B. D. Reddy·P. Steinmann·A. Kergassner
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Abstract

As an extension to strain-gradient models of size-dependent plastic behaviour, this work proposes a model for a stress-gradient theory. The model is distinguished from earlier works on the topic by its being embedded in a thermodynamically consistent framework. The development is carried out in the context of single-crystal plasticity, and draws on thermodynamically consistent models for single-crystal conventional and strain-gradient plasticity. The model is explored numerically using the example of torsion of a thin wire comprising a face centred cubic crystal, and its behaviour compared with that based on a recent disequilibrium density model of size-dependent plasticity.

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B. D. Reddy, P. Steinmann, A. Kergassner. 2020-07-30. A thermodynamically consistent theory of stress-gradient plasticity. https://doi.org/10.1016/j.jmps.2020.104266

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