Effects of nitrogen on deformation-induced martensitic transformation in metastable austenitic Fe-18Cr-10Mn-N steels

The effects of nitrogen content on deformation-induced martensitic transformation (DIMT) in Fe-18Cr-10Mn-N alloys were investigated. During tensile deformation, the stress-strain response was changed at different transient strains (epsilon congruent to 0.19-0.22) depending on the nitrogen content. At the beginning of the deformation, a gamma -> epsilon martensitic transformation occurred, whereas the formation of alpha '-martensite was predominant after transient strain. Increasing the nitrogen content caused the transient strain for DIMT to shift to higher strain and, finally, DIMT did not occur when nitrogen content was above 0.5 wt.%. (c) 2007 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.