In-situ neutron diffraction during tension-compression cyclic deformation of a pearlite steel

Tension-compression cyclic deformation of a pearlite steel was investigated using in-situ neutron diffraction, in order to make clear the mechanisms of high work hardening, large Bauschinger effect and particularly cyclic softening. The high work hardening and large Bauschinger effect are mainly caused by phase stresses generated by plastic misfit strains between ferrite and cementite. Cyclic softening was observed in tension-compression test, the reason of which was presumably softening of ferrite phase due to reversible motion of dislocations. The changes in phase stress and Full-Width at Half Maximum shows good correspondence during cyclic deformation.