Role of dissipation processes in experiments on overall extension and compression in explosive loading of spheres

Features of the realization and calculation of the overall extension and co mpression of spheres under explosive loading are analyzed. The dependence o f the characteristics of such regimes on the dynamic-yield stress, the dyna mic-viscosity coefficient, and the spall strength of the sphere material is studied within the framework of a consistent elastoviscoplastic model. It is shown that the dissipation losses due to the work of the strength and vi scosity forces play a significant role in the course of physical processes near the center of the sphere. Taking into account their effects on the cha nges in the yield stress and the dynamic-viscosity coefficient according to the amount of dissipated energy in each element of the sphere volume, one can consistently describe the available experimental results.