Detwinning and strain hardening of an extruded magnesium alloy during compression

The plastic deformation of an extruded Mg–Al–Mn (AM30) magnesium alloy in the extrusion direction by compression can be characterized by three distinct stages. Twinning was observed in stage A with a decreasing strain-hardening rate. Detwinning occurred due to strong twin–dislocation interactions in stage B, which was represented by an increasing strain-hardening rate over an extended strain range. Stage C with a decreasing strain-hardening rate was due to a reducing resistance of fewer twins to the dislocation slip.