Constitutive modeling of phase transition in iron under sweeping detonation wave loading

The alpha-epsilon phase transition in shock loaded iron is well-known from numerous plate impact tests by the very accurately determined phase transition pressure value of 13 GPa. However, a more recent experimental study, using a sample loaded by a sweeping detonation wave, has found that a drop in the specific volume due to the transition during non-planar loading is not linked directly with the phase transition pressure value. The present analysis employing a two-phase model with the phase transition kinetic considers contribution from the shear stress at the loading resulting in the phase transition and kinetic character of the transition. The analysis demonstrates that taking these factors into account improves the accuracy of the description of the experimental data.