Effect of Cr content on the TWIP behavior in Fe-Mn-Cr Steels

The characteristics of the martensitic transformations induced by uniaxial tensile tests performed between room temperature and 200 degrees C in two Fe-Mn-Cr alloys with different Cr contents were examined. Different volume fraction of alpha' martensite and epsilon martensite were detected in the austenitic matrix as the function of parameters of the thermo-mechanical treatments. Quantitative and qualitative phase analyses by X-ray diffraction were carried out on the samples. The crystallographic orientation (texture) of the phases on macro scale was also determined. The decomposition of epsilon martensite was followed by DSC measurements. It was found that increasing Cr content increased the stability of austenite, thus, increased the stacking fault energy. The increased Cr content also suppressed the formation of alpha' martensite. Deformation of austenite stabilized the austenite phase and led to the formation of textured epsilon martensite. (C) 2015 The Authors. Published by Elsevier Ltd.