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Dislocation Extraction Algorithm (DXA)

Introduction

The dislocation extraction algorithm (DXA) is a computational analysis technique developed by Alexander Stukowski at Darmstadt University of Technology, Germany. It can identify dislocation defects in atom-position datasets generated by atomistic simulations such as molecular dynamics. The algorithm converts all identified dislocations into continuous lines and computes their Burgers vectors in a fully automated fashion. The original DXA method has been described in this article [MSMSE 18, 085001].

Program code

This website used to host the first implementation of the original DXA algorithm developed in 2010, which was limited to face-centered cubic and body-centered cubic crystals and is now outdated. Please understand that I am no longer able to support the old analysis code. If you need the old code for some reason, it can still be found here. Note that the old code is no longer compatible with recent versions of LAMMPS!

However, a new and more robust code has been developed that implements a generalized and extended version of the DXA algorithm, which was described in a recent paper [MSMSE 20, 085007]. Please write me an email if you are interested in using the new code to analyze your simulations. The rewritten analysis tool supports a much wider range of crystal lattice types and can identify partial dislocations as well as grain boundary dislocations. Moreover it allows to calculate the inherent elastic strain field and can decompose atomic-level crystal deformation into plastic and elastic parts as described in this article [MSMSE 20, 035012]. Last but not least, the new implementation is fully parallelized (based on MPI).

Alexander Stukowski

Contact

If you have any questions about the DXA method, please contact me (that is Alexander Stukowski) at stukowski@mm.tu-darmstadt.de.

I'm a research group leader in the Materials Modeling Division at Darmstadt University of Technology, Germany.

Please also check out my visualization software OVITO and my other publications.

Example

The following movie shows the results of the dislocation extraction algorithm (DXA) when applied to a large-scale MD simulation of single crystalline aluminum under tensile loading. Two notches on the sides of the crystal acted as nucleation sites for dislocation loops.

Flash must be installed to watch the movie on this page.
Download movie file (MPEG4: 25 MB)