This link my help

https://icme.hpc.msstate.edu/mediawiki/index.php/Uniaxial_Tension.html

best

A

The link provided by Alberto Fraile is helpful, and this input script is suitable for tensile simulation with periodic boundary condition (PBC). We usually use "deform command " for PBC, while "velocity command" for non-periodic condition.

have a look at "fix" and "deform" command in lammps. Something like this:

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fix 3 all deform 1 z erate 0.0001 units box remap x

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