Simulation study on influence of component thickness on dwell-penetration transition time of long rod projectile impacting ceramic armour module

Abstract

The influence of component thickness of ceramic armour performance against long rod projectile is a critical information for the process of armour design optimization. In this study, the correlation between dwell time and cover plate thickness and mechanism shift with different ceramic to backing plate thickness ratio were studied using hydrocode simulation software LS-Dyna. The projectile is a long rod projectile with a length to diameter ratio of 14 at a nominal velocity of 1.25 km/s. In this study the cover plate performance is studied based on a surrogate module configuration, where the backing thickness is 10 mm instead of the usual semi-infinite thickness backing which has minimal bending deformation. The parameters used in the simulation were calibrated against experimental data in previous studies. From the study, the cover plate needs a minimal thickness to establish dwell. For thicker cover plate, the dwell time starts to decrease due to the confinement provided by thickness of the cover, which limited the lateral flow of the cover plate. This restriction of lateral flow, resulted in pressure build-up at the ceramic surface, thus, reducing the dwell time.