Code: GTA
Inlcuded is a Grain Tracking Algorithm (GTA) for two different example simulations. This interface is somewhat specific to our interests regarding nanocrystalline metals, but many of the functions contained within the GTA can be modified for or applied to other materials applications. All of the codes are included in this package for your perusal. If any other questions arise, please do not hesitate to email Jason Panzarino at jpanzari@uci.edu or Dr. Timothy Rupert at trupert@uci.edu. More information about this tool can be found in the following article:
Panzarino J F and Rupert T J 2014 Tracking Microstructure of Crystalline Materials: A Post-Processing Algorithm for Atomistic Simulations JOM 65 417-428
Main Scripts The following are the main driving functions used by the GTA and their application:
| Main Driving Function | Application |
|---|---|
| GRAINIDENT1.m | Identification of crystallites |
| GRAINHISTORYEXECUTABLE.m | Mapping of MD time steps |
| periodic_boundaries.m | Builds periodic boundaries |
| OrientBCC | Calculate BCC orientation axis |
| OrientFCC | Calculate FCC orientation axis |
| Misorientation9f.m | Calculates misorientation between axis |
Proper input format
In order to use the graphical user interface (GUI) the input file from LAMMPS must be in same format as the example files given. To obtain this output from LAMMPS the following columns were calculated and output during the molecular dynamics simulation. “Scaled” refers to the scaled simulation coordinates, and “coord” references the unscaled coordinates. Common neighbor analysis (CNA) and Centro-Symmetry Parameter (CSP) are also listed. The GTA only requires CSP to identify grains, however we output CNA from the MD simulation as well since a simple modification to the GRAINIDENT1.m script could be done to use this metric instead. [1]
| x-scaled | y-scaled | z-scaled | X-coord | Y-coord | Z-coord | CNA | CSP |
A pdf file of the Instructions is available. Please refer to the documentation to learn how to use this tool.
