Animation shows the grid development during the growth of a polycrystalline material, in a two dimensional 1 micron square.
A portion of a grain boundary between two misoriented crystals. The sequence of images shows the multiscale resolution, finally resolving the dislocation array comprising the grain boundary.
The goal of this project is to develop multiscale methods for simulating the development of materials microstructure. Our approach is based upon a continuum representation of atomic density, obeying diffusive dynamics. During the course of this project we have developed analytical methods to describe the coarse-grained dynamics of the atomic density. In the last year, these equations have been solved by implementing adaptive mesh refinement, enabling a thousand-fold increase in speed compared to a atomic-scale resolved simulation.
The work described herein was performed by an interdisciplinary team of mechanical engineers and theoretical physicists. Three students have been associated with this project, including one who has graduated and moved to industry. Our project has educated mechanical engineers in renormalization techniques, and physicists in adaptive mesh refinement techniques.
In the lower image, we show a portion of a grain boundary between two misoriented crystals. The sequence of images shows the multiscale resolution, finally resolving the dislocation array comprising the grain boundary. This work shows enables the solution of problems in materials science, seamlessly integrating length scales from nanoscopic to mesoscopic.
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