High Velocity Impact Testing of Structural Reactive Projectiles

This study examined the dynamic response of structural reactive projectiles penetrating through an aluminum target then impacting an inert steel anvil at speeds up to 1500 m/s. The impact testing is performed using a High-velocity Impact-ignition Testing System (HITS). The projectiles consist of a thermite with a high loading ductile metallic binder, consolidated into a cylindrical pellet contained in a .410 caliber shot gun case. The thermite includes aluminum fuel particles that were stress altered prior to their consolidation. This study considers the effect of stress altering aluminum particles on the overall penetration dynamics and reactivity of the projectile. Results demonstrate the range of plate deformation mechanics and overall transient pressure data that can be used to interpret reactivity. A threshold impact velocity was observed that corresponds with fragmentation of the projectile and is a function of stress-altered particles. The differences in reactivity between stress altered and untreated aluminum powder likely stem from the fragmentation field created upon penetration of the plate. Results provide a fundamental understanding of penetration and impact events with structural reactive formulations.