Impact-induced twinning and phase transition in a medium carbon steel

Deformation twinning in a medium carbon steel containing ferrite and pearlite under shock compression is investigated below and above the α–ε phase transition stress (σT), within a peak stress range of 10–20 GPa. Free surface velocity histories are measured to obtain the Hugoniot elastic limit (2.7 GPa), σT (13.3 GPa) and bulk plastic strain. Postmortem samples are characterized with electron backscatter diffraction and transmission electron...