The role of mechanical twinning on the fragmentation and the contribution to strengthening was studied using single crystals of Hadfield steel after high-pressure torsion and rolling at room temperature. Multiple twinning was found to be the basic deformation mechanism responsible for the fast generation of an ultrafine-grained microstructure with twin boundaries in Hadfield steel single crystals after severe cold plastic deformation. As a result, the hardness of the Hadfield steel increased noticeably.

The Role of Twinning on Microstructure and Mechanical Response of Severely Deformed Single Crystals of High-Manganese Austenitic Steel. E.G.Astafurova, M.S.Tukeeva, G.G.Zakharova, E.V.Melnikov, H.J.Maier: Materials Characterization, 2011, 62[6], 588-92