Penetration modeling of ceramic and metal targets

Abstract

Examining the centerline momentum balance with assumed velocity fields has proven to be very effective in analyzing penetration problems. Models based on this technique inherently include transient effects. This survey paper presents analytic models for both metal and ceramic targets, and then compares with experiment and large scale numerical simulation. INTRODUCTION Recently, a technique has been introduced that gives remarkably good results in modeling projectile penetration of targets. This technique is to integrate the momentum balance along the centerline. Velocity profiles are assumed in both the target and the projectile in order to carry out the integration. In order to determine the shear stress response required in the integral, it is also necessary to assume a constitutive model for the target material and a three-dimensional velocity field within the target This technique was first applied to metal targets being penetrated by long rods [1], and has subsequently been successfully applied to thick ceramic targets [2,3] and to thin targets comprised of thin ceramic tiles backed by thin substrates [4]. The constitutive models for target response that have been successfully analyzed to date with this method include von Mises plasticity [1], with a constant flow stress, and also a Drucker-Prager yield criterion with a cutoff [3]: