Comparative studies on near-threshold fatigue crack propagation behavior of high manganese steels at room and cryogenic temperatures

The near-threshold fatigue crack propagation behavior of high manganese steels, including 24Mn4Cr, 22Mn3Cr, 20Mn, 18Mn and 12Mn steels, were examined at 298, 173 and 113 K, and the results were compared to those of widely used cryogenic alloys, including STS304, 9% Ni and 5% Ni steels. The near-threshold FCP behavior of high manganese steels was in general excellent at both room and cryogenic temperatures as compared to the reference cryogenic steels. The near-threshold Delta K values tended to be inversely proportional to the stacking fault energy values of high manganese steels. The fractographic analysis suggested that the SFE mostly affected the slip reversibility of high manganese steels in near-threshold Delta K regime. (C) 2015 Elsevier Inc. All rights reserved.