To help you kick start the usage of FE2AT, we provide the example of bending of a molybdenum beam(the first demonstration example in the FE2AT paper).

In what follows, <FE2AT_dir> refers to the directory/path to where you downloaded the source of FE2AT.

Prerequisites:

• Linux operating system (FE2AT is verified to work on openSuSE 12.2 and 13.1, and on Ubuntu 14.04)
• Abaqus CAE (if you want to visualize the FE simulation)
• Enough memory (RAM) to handle the problem under consideration (This example was run on a machine with 32GB RAM)
• Ovito for visualization of atomistic samples

Go to the example directory and unzip the atomistic configuration file

$> cd <FE2AT_dir>/example_bending $> gunzip Mo_wire_x011y100z01-1_1250x150x150.imd.gz

List the contents of the folder

$> ls

Mo_wire_x011y100z01-1_1250x150x150.imd Mo_y1250_xz150_xbend70A.displacements Mo_y1250_xz150_xbend70A.elements Mo_y1250_xz150_xbend70A.fe2atparam Mo_y1250_xz150_xbend70A.nodes Mo_y1250_xz150_xbend70A.odb

Details of constituent files

• Mo_y1250_xz150_xbend70A.fe2atparam --> Parameter file for FE2AT
• Mo_y1250_xz150_xbend70A.odb --> Output database of FE simulation
• Mo_y1250_xz150_xbend70A.nodes --> File containing nodal coordinates
• Mo_y1250_xz150_xbend70A.elements --> File containing element connectivity
• Mo_y1250_xz150_xbend70A.displacements --> File containing nodal displacements obtained from FE simulation
• Mo_wire_x011y100z01-1_1250x150x150.imd --> Undeformed atomistic configuration

Visualize the atomistic sample

ovito Mo_wire_x011y100z01-1_1250x150x150.imd

Have a look on the FE simulation

Invoke Abaqus

abaqus cae &

Load Database

'File' -> 'Open ...' -> File filter: 'Output Database (*.odb*)' Select 'Mo_y1250_xz150_xbend70A.odb'

The undeformed, meshed, nanowire is shown

You can rotate the view by simulaneously pressing 'Ctrl + Alt + Left mouse button' and moving the mouse. You can translate the view by simulaneously pressing 'Ctrl + Alt + Middle mouse button' and moving the mouse.

Show the deformed state

'Plot' -> 'Deformed Shape'

Execute FE2AT

We now map the nodal displacements from the FE simulation onto the atomistic configuration. For this, you need to compile FE2AT. For instructions on how to compile, please see FE2AT usage details

<FE2AT_dir>/source/<FE2AT_executable> -p Mo_y1250_xz150_xbend70A.fe2atparam

<FE2AT_executable> is the executable created after compilation. For example, with version 3.0, the executable would be FE2ATmap_V3.0.x

Output

After successful execution of FE2AT, three output files are to be found in the directory.

Mo_wire_x011y100z01-1_1250x150x150_xbend70A.imd --> File containing the coordinates of the deformed atomistic configuration (to be used for subsequent simulations).

FE2ATmap_output_notallocated.xyz --> File containing atoms that might not have been allocated to any element.

FE2ATmap_benchmark_ForRewAlgo.dat --> File containing some benchmark information

The resulting deformed atomistic configuration Mo_wire_x011y100z01-1_1250x150x150_xbend70A.imd is in the IMD format and can be visualized with Ovito.

ovito Mo_wire_x011y100z01-1_1250x150x150_xbend70A.imd

For reference and completeness, the output is also provided along with the example and can be found in the subdirectory Output_example_bending.

CONGRATS! - You have now successfully run the example!!