Viscoelastic model of impact ignition of solid explosives

A physicomathematical model is developed for the nonisothermal deformation of a disk, which is made of an incompressible, elastoplastic material, during an impact. The model takes into account the formation in the radial flow of viscous boundary layers at the contact boundaries on the striker and the anvil. In spite of their small thickness and the short duration, the boundary layers serve as effective concentrators of the dissipated impact energy and play a decisive role in the processes of thermal softening of the material and of the disk disintegration. The model is used to compute the critical conditions and the principal characteristics for the mechanical initiation of solid explosive charges. The good agreement between the theoretical and experimental data on the impact sensitivity of the explosive lends support to our concepts of the nature of explosion initiation using mechanical effects, on which the model was founded.