Is Dislocation Flow Turbulent in Deformed Crystals?

摘要

Intriguing analogies were found between a model of plastic deformation in crystals and turbulence in fluids. A study of this model provides remarkable explanations of known experiments and predicts fractal dislocation pattern formation. Further, the challenges encountered resemble those in turbulence, which is exemplified in a comparison with the Rayleigh-Taylor instability. From horseshoes and knives to bridges and aircrafts, mankind has spent five millennia studying how the structural properties of metals depend not only on their constituents, but also how the atoms are arranged and rearranged as metals are cast, hammered, rolled, and bent into place. A key part of the physics of this plastic distortion is played by the motion of intrinsic line defects called dislocations, and how they move and rearrange to allow the crystal to change shape.