Dislocation Cell Wall Patterns

March Meeting 2010

Cell wall patterns for the relaxed, stress-free state of an initially random distortion


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

The Laboratory of Atomic and Solid State Physics (LASSP)
Cornell University
Ithaca, New York

Dislocation Cell Wall Patterns

Cell wall patterns for the relaxed, stress-free state of an initially random distortion. Top: Dislocation climb is allowed; Bottom: Glide only. 

Left: Net dislocation density |ρ|. (A) When climb is allowed, the resulting grain boundaries are sharp, regular, and at the system scale; there is little substructure. (C) When climb is forbidden, there is a hierarchy of walls on a variety of length scales, getting weaker on finer length scales.

Right: Corresponding local orientation maps, with the three components of the orientation vector mapped onto RGB values. Notice the clear grains in (B), and the fuzzier cell walls in (D).

References

Bending crystals: The evolution of grain boundaries and fractal dislocation structures, Yong S. Chen, Woosong Choi, Stefanos Papanikolaou, and James P. Sethna.

Usage Information

Reporters may freely use this image as long as they include the following credit: "Image courtesy of Yong S. Chen/Cornell University".

For further information, contact:
Jason Bardi
(301) 209-3091