5th International High Manganese Steel Conference - HMNS 2022

The goal of the research carried out using static and dynamic FWM and HPB methods was to obtain material characteristics, and most of all a detailed analysis of changes occurring in the high manganese steel microstructure in a broad range of deformation rates and deformation magnitudes. The research confirmed that deformation of steel in the static range occurs mainly via dislocation glide. It is proved by the presence of free dislocations, double dislocation walls and cellular structure in the microstructure. Sporadically, twins have been observed in the form of single bundles. Under dynamic conditions, the contribution of the twinning mechanism in the deformation of the steel increases. The increase in deformation rates leads to an increase in twinning intensity. Simultaneously, a continuous transformation of the dislocation structure occurs. Bulging of grain boundaries constitutes a structural effect proving a high deformation energy released during the tests with a high strain rate. A characteristic effect under these conditions consists in formation of shearing microbands and bands with diversified morphologies. The results of structural investigations became a basis for development of original models of structural changes depending on the deformation parameters were distinguished.