5th International High Manganese Steel Conference - HMNS 2022

Hadfield steel shows high strain hardening which can be linked to its ability to form twins during mechanical loading. Twinning in Hadfield steel is well documented. However, detwinning in Hadfield steel is only barely investigated but might be an essential effect as during cyclic loading detwinning provides an additional contribution to plastic deformation.
In order to gain more information regarding the deformation behavior in Hadfield steel, the present work concentrates on the twinning and detwinning behavior during interrupted tensile tests. The tensile tests were conducted in-situ within a scanning electron microscope (SEM) and interrupted at different elongations. To determine the formation of twins after every interruption, the electropolished tensile test sample was analyzed by electron backscatter diffraction (EBSD). It is shown that twinning in a certain region takes place within one cycle of tensile straining, whereas partial detwinning of the twinned regions takes place over a few tensile loading/unloading cycles. Furthermore, the kernel average misorientation of the twinned and detwinned region is analyzed. High values of misorientation are found in the detwinned regions, which can be linked to the detwinning process.