8.5. Dislocation helix with a loop
To create a dislocation helix combined with a loop,
Step 1:
Use the tool in subdirectory tools/Bcc to creat a BCC crystal sample:
bcc_reg.lmp, use the shell script 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#those started with '#' are comment lines
2#crystal region
3Region
4-x 1 -1 0 # lattice orientation in x-direction
5-y 1 1 -2 # lattice orientation in y-direction
6-z 1 1 1 # lattice orientation in z-direction
7-lat 2.867 # lattice constant of Fe
8-pbc 1 1 1 # boundary condition flag: '1': pbc, '0': non-pbc
9
10nHelix 1
11Helix
12-bvh 1 1 1
13-bsh 1/2
14-f mesh.dat
15
16#dislcoation
17nLoop 1 # number of dislocaito loops
18Loopn # label of a dislocation section
19-bv 1 1 1 # orientation of Burgers vector
20-bs -1/2 # scalar coefficient of Burgers vector, e.g., 1/2 in: 1/2<110>
21-dnorm 1 -1 0 # normal direction of plane with dislocation loop
22-dc 0 25 0 # center of dislocation loop
23-dr 25 # radius of dislocaiton loop of half of the edge of square loop
24-lx 1 1 -2 # local x axis on slip plane
25-ly 1 1 1 # local y axis on slip plane
26-ndisl 4 2.4 # segments of a discretized dislocation loop