Influence of carbon on the microstructure of a Fe-Mn-Si-Cr-Ni alloy

The influence of the addition of C to the Fe-Mn-Si-Cr-N base material is investigated at room temperature. Steel samples were deformed during a tensile experiment up to a strain of 17 %. Light optical microscopy (OM) and XRD gave information about the different micro-structural phases that exists in the deformed and the undeformed alloys. The evolution of the defect structure is followed by positron annihilation techniques such as Doppler broadening of annihilation radiation spectroscopy (DBAR) and the positron annihilation lifetime spectroscopy (PALS). During deformation a martensitic e-phase is induced. The size of the martensite plates increases with increasing deformation