Several high explosive formulations have recently been compared in a series of impact tests where samples of each composition were encased in a test fixture designed in flat geometry mocking an HE loaded artillery projectile. The purpose of the ongoing test series is to determine the relative rate of chemical energy release or explosiveness of several standard and research insensitive high explosive (IHE) main charge compositions. The triggering stimulus is the impact of .30 calibre ball bullets fired at normal muzzle velocity.

By means of a computational approach based on classical molecular dynamics, we can begin to form a realistic picture of shock-induced processes occurring at the shock front and resulting from the detailed, violent motion associated with shock motion on an atomic scale. Prototype studies of phase transitions will be discussed. We will also examine the interaction of the shock front with defects, surfaces, voids, and inclusions, and across grain boundaries. We will focus on the critical question of how mechanical energy imparted to a condensed material by shock loading is converted to the activation energy required to overcome some initial energy barrier in an initiation process.