Ricochet of 0.3″ AP projectile from inclined polymeric plates

Abstract

When a rigid armor piercing (AP) projectile impacts an inclined plate it can be deflected by the asymmetric forces, which the target exerts on the projectile. This is a well-known phenomenon which has been investigated by several workers impacting various metallic targets with AP projectiles. These works have shown that if the incidence angle is small enough the projectile can ricochet from any metallic target, provided the target is thick enough. In the present study we investigated the deflection, and ricochet, of 0.3″ AP projectiles impacting inclined polymeric targets, which, to our best knowledge, were not investigated before. We concentrate our attention on Plexiglas targets, which turned out to exert the strongest asymmetric forces on the AP projectile. We present a thorough 3D numerical study following the important properties of the target, which control the ricochet and deflection processes. It turns out that these properties are the high compressive strength and the low tensile strength of the target. In other words, the high brittleness of Plexiglas is responsible for the large deflection which was observed in our experiments. Other polymers, less brittle, resulted in a much lower effect or no effect at all.