Microstructure Defects Contributing to the Energy Absorption in CrMnNi TRIP Steels

Authors


  • The authors thank the German Research Foundation (DFG) for financial support of these investigations in frame of the Collaborative Research Centre (SFB) 799. We also thank Dr. A. Jahn from the Institute of Steel Technology, Technische Universität Bergakademie Freiberg for the hot rolled TRIP steel samples. For the metallographic sample preparation we would like to thank Mrs. Dipl.-Ing. A. Mueller, Mrs. K. Becker; for the conventional preparation of TEM samples and the FIB preparation of TEM samples on Infineon, Dresden we would like to thank Mrs. Dipl.-Ing. A. Leuteritz.

Abstract

Microstructure defects control the TRIP effect and/or the TWIP effect and contribute significantly to the absorption of deformation energy in plastically deformed austenitic CrMnNi steels. In this study, the propagation and interaction of dislocations, stacking faults and twins connected with the formation of Lomer-Cottrell locks, stacking fault tetrahedra, dislocation clusters, deformation bands, microtwins with high-energy incoherent twin boundaries and the nucleation of α′- martensite in the areas of the high local lattice strain due to the fluctuation of the stacking fault density and the lattice shearing, were analysed in the CrMnNi TRIP steel after different deformation extents via transmission electron microscope with high resolution and via scanning electron microscope.

Ancillary