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arXiv · 1609.07553

Controlling Strain Bursts and Avalanches at the Nano-to-Micro Scale

Yinan Cui·Giacomo Po·Nasr Ghoniem
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Abstract

We demonstrate, through 3-dimensional discrete dislocation dynamics simulations, that the com- plex dynamical response of nano and micro crystals to external constraints can be tuned. Under load rate control, strain bursts are shown to exhibit scale-free avalanche statistics, similar to critical phenomena in many physical systems. For the other extreme of displacement rate control, strain burst response transitions to quasi-periodic oscillations, similar to stick-slip earthquakes. External load mode control is shown to enable a qualitative transition in the complex collective dynamics of dislocations from self-organized criticality to quasi-periodic oscillations.

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Yinan Cui, Giacomo Po, Nasr Ghoniem. 2016-09-24. Controlling Strain Bursts and Avalanches at the Nano-to-Micro Scale. https://doi.org/10.1103/physrevlett.117.155502

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