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arXiv · 1001.5053

Bending crystals: Emergence of fractal dislocation structures

Yong S. Chen·Woosong Choi·Stefanos Papanikolaou·James P. Sethna
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Abstract

We provide a minimal continuum model for mesoscale plasticity, explaining the cellular dislocation structures observed in deformed crystals. Our dislocation density tensor evolves from random, smooth initial conditions to form self-similar structures strikingly similar to those seen experimentally - reproducing both the fractal morphologies and some features of the scaling of cell sizes and misorientations analyzed experimentally. Our model provides a framework for understanding emergent dislocation structures on the mesoscale, a bridge across a computationally demanding mesoscale gap in the multiscale modeling program, and a new example of self-similar structure formation in non-equilibrium systems.

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Yong S. Chen, Woosong Choi, Stefanos Papanikolaou, James P. Sethna. 2010-08-18. Bending crystals: Emergence of fractal dislocation structures. https://doi.org/10.1103/physrevlett.105.105501

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