Inelastic rotations and pseudoturbulent plastic avalanches in crystals
R Baggio1,2,3, O U Salman1, L Truskinovsky2
1LSPM, CNRS UPR3407, Paris Nord Sorbonne Université, 93400 Villateneuse, France.
Physical Review. E
|March 18, 2023
Summary
Crystal plasticity creates complex textures through microslips that self-organize into laminates. This "wrinkling" effect, driven by dislocations, leads to unstable, pseudoturbulent rotations requiring probabilistic descriptions.
Area of Science:
- Materials Science
- Solid Mechanics
- Crystallography
Background:
- Plastic deformation in crystals results in microstructures with complex textures.
- These textures feature randomly oriented, unstressed lattice patches.
Purpose of the Study:
- To investigate the origin of rotations within crystal plasticity textures.
- To model the self-organization of microslips and their resulting microstructures.
Main Methods:
- Utilized a mesoscopic Landau-type tensorial model for crystal plasticity.
- Conducted numerical experiments to simulate microstructural evolution.
Main Results:
- Identified crystallographically exact microslips as the origin of rotations.
- Observed self-organization into pseudotwin-type laminates, termed internal "wrinkling".
- Revealed pseudoturbulent effective rotations with power-law spatial correlations.
Conclusions:
- The internal "wrinkling" is a dissipative, dislocation-mediated process.
- Dislocational self-organization is inherently unstable.
- A probabilistic description is necessary for crystal plasticity.
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