Experimental investigation of shock waves under steady state conditions in a polymerized epoxy resin

In experiments on uniaxial shock compression, the structure of the shock-wave front in a polymerized epoxy resin was studied in the pressure range $0.8$–$2.7$ GPa. The VISAR laser interferometry method was used to measure the velocity profiles of the surfaces of the studied samples when shock waves arrives at them. The shock Hugoniot is obtained in particle velocity–shock-wave velocity coordinates. It was found that the exponent of the dependence relating the maximum longitudinal strain rate in the shock-wave front and the pressure behind the front, $\dot \varepsilon_x \sim P^n$, is equal to $5.5$, which exceeds the value of $4$ typical for solid materials. The question of whether shock waves reach a steady state in the studied regimes is considered.