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arXiv · 1602.02981

Barrier effect of grain boundaries on the avalanche propagation of polycrystalline plasticity

Tomoaki Niiyama·Tomotsugu Shimokawa
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Abstract

To investigate the barrier effect of grain boundaries on the propagation of avalanche-like plasticity at the atomic-scale, we perform three-dimensional molecular dynamics simulations by using simplified polycrystal models including symmetric-tilt grain boundaries. The cut-offs of stress-drop distributions following power-law distributions decrease as the size of the crystal grains decreases. We show that some deformation avalanches are confined by grain boundaries; on the other hand, unignorable avalanches penetrate all the grain boundaries included in the models. The blocking probability that one grain boundary hinders this system-spanning avalanche is evaluated by using an elemental probabilistic model.

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Tomoaki Niiyama, Tomotsugu Shimokawa. 2017-01-18. Barrier effect of grain boundaries on the avalanche propagation of polycrystalline plasticity. https://doi.org/10.1103/physrevb.94.140102

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