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arXiv · 2008.09056

Dislocation impediment by the grain boundaries in polycrystals

Yinguang Piao·Khanh Chau Le
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Abstract

Thermodynamic dislocation theory incorporating dislocation impediment by the grain boundaries is developed to analyze the shear test of polycrystals. With a small set of physics based material parameters, we are able to simulate the stress-strain curves for the load and its reversal, which are consistent with the experimental curves of Thuillier and Manach [2009]. Representative distributions of plastic slip under load and its reversal are presented, and their evolution explains the extended length of the transition stage during load reversal.

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Yinguang Piao, Khanh Chau Le. 2020-08-20. Dislocation impediment by the grain boundaries in polycrystals. https://arxiv.org/abs/2008.09056

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