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

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.

5 pages, 3 figures

References in corpus (2)

• Atomistic mechanisms of intermittent plasticity in metals: Dislocation avalanches and defect cluster pinning
• Dislocation interactions mediated by grain boundaries

Cited by in corpus (4)

• Avalanches and Plastic Flow in Crystal Plasticity: An Overview
• Ice : The paradigm of wild plasticity
• Structural relaxation affecting shear transformation avalanches in metallic glasses
• Fluctuations in crystalline plasticity