# Mg Single Crystals LAMMPS input file # Tian Tang, 2010 # Description: This input file for LAMMPS runs 15 cycles of a fatigue crack growth simulation # with the EAM Magnesium potential for a single crystal. units metal boundary p m p atom_style atomic read_data datafile1 pair_style eam/fs pair_coeff * * Mg_mm.eam.fs Mg neighbor 0.3 bin neigh_modify delay 1 # define groups region upper block INF INF 290.000000 INF INF INF units box region lower block INF INF INF -290.000000 INF INF units box region center block -180 180 -70 70 INF INF units box group center region center group upper region upper group lower region lower group mobile subtract all lower upper # fixs fix 1 all nve fix 2 upper setforce 0.0 0.0 0.0 fix 3 lower setforce 0.0 0.0 0.0 # equilibrate velocity mobile create 100.0 4928459 rot yes dist gaussian fix 4 mobile temp/rescale 100 100.0 100.0 0.1 1.0 run 2000 # compute centrosymmetric number and stress components compute 1 all centro/atom compute 2 all ackland/atom compute 3 all stress/atom compute myTemp mobile temp/partial 1 0 1 compute mypress all pressure myTemp thermo 1 thermo_style custom step c_myTemp etotal c_mypress f_2[2] f_3[2] thermo_modify format 1 %5d thermo_modify format 2 %22.12f thermo_modify format 3 %22.12f thermo_modify format 4 %22.12f thermo_modify format 5 %22.12f thermo_modify format 6 %22.12f # unfixs unfix 1 unfix 4 # new fixs fix 1 all nvt 100.0 100.0 10.0 drag 100.0 fix_modify 1 temp myTemp reset_timestep 0 dump 1 all custom 1000 Ensight1/dump.custom.* id type x y z c_1 c_2 c_3[2] dump_modify 1 format "%d %d %10.5f %10.5f %10.5f %7.2f %7.2f %10.5f" dump_modify 1 thresh c_1 > 11.5 dump 2 center custom 1000 Ensight1A/dump.custom.* id type x y z c_1 c_2 c_3[2] dump_modify 2 format "%d %d %10.5f %10.5f %10.5f %7.2f %10.5f %10.5f %10.5f %10.5f %10.5f %10.5f" dump 3 all custom 1000 Ensight1B/dump.eampost id x y z c_1 dump_modify 3 format "%d %10.5f %10.5f %10.5f %10.5f" # Apply cyclic loading # ------------------------------------------------------------ #CYCLE 1-LOADING velocity all ramp vy -0.4350 0.4350 y -290.000 290.000 sum yes units box uncompute myTemp compute myTemp mobile temp/ramp vy -0.4350 0.4350 y -290.00 290.00 units box run 30000 #CYCLE 1-UNLOADING velocity all ramp vy 0.8700 -0.8700 y -290.000 290.000 sum yes units box uncompute myTemp compute myTemp mobile temp/ramp vy 0.8700 -0.8700 y -290.00 290.00 units box run 6000 # ------------------------------------------------------------ print "All done"