Influence of flow stress and strain hardening of high strength structural steel on the necking formation under dynamic tension

A numerical analysis on the thermo-viscoplastic behaviour of high strength structural steels when subjected to dynamic tension has been conducted. Using the calibration conducted by Nemat-Nasser and Guo (Mech. Mat. 35 (2003) 1023-1047) for DH-36 steel, the influence of the flow stress level and the strain hardening on necking formation and Critical Impact Velocity has been analysed. The numerical results obtained are compared with analytical predictions. Localization of necking and CIV values are directly linked to strain hardening parameters.