8.4. Dislocation helix

_images/helices.png
Dislocation helices with uniform radius (left) and with linearly varying radius (right).

To create a dislocation helix,

Step 1:

Use the tool in subdirectory tools/Bcc to creat a BCC single crystal sample: bcc_reg.lmp, use the tool in subdirectory Tool/Helical_surface to create the mesh of a helical surface: mesh.dat;

Step 2:

Open terminal, run the following command:

1CryDisGen para_file bcc_reg.lmp

Parameter file

Content of the para_file:

 1#line starting with '#' are comments
 2#crystal region definition
 3Region
 4-x     1 -1  0         # lattice orientation along x-axis
 5-y     1  1 -2         # lattice orientation along y-axis
 6-z     1  1  1         # lattice orientation along z-axis
 7-lat   2.867           # lattice constant of Fe
 8-pbc   1 1 1           # boundary condition flags along x/y/z-axes: '1' for periodic, '0'for non-periodic
 9
10#dislocation helix
11nHelix 1               # number of dislocation helices
12Helix                  # label for dislocation helix section
13-bvh   1  1  1         # orientation of the Burgers vecotr for the helix
14-bsh   1/2             # scalar coefficient of Burgers vector, e.g., 1/2 in 1/2<110>
15-f     mesh.dat        # mesh data file of the helical surface