Front structure of a weak shock wave in dense composites

The structure of the compression-pulse front in a heterogeneous energy material with a characteirstic size of granules of 100–300 $\mu$m and its inert simulator with a particle size of 3–5 mm is studied experimentally. Shock waves with an amplitude of the order of 0.1GPa were initiated by a 20-g explosive charge. The velocity of the free surface of the samples or the velocity on the boundary with a water window was recorded by a VISAR laser interferometer. It is shown that the variation in the mass rate in an energy material is of oscillating character, which is explained by the heterogeneous structure of the samples. Oscillations were not observed in a finely dispersed simulator. In addition, it is shown that the viscoelastic Maxwell model is suitable for averaging the description of the evolution of the compression pulse in the studied materials.