Study Onnumerical Modeling Of Ballisticdamage Mechanisms Of Ceramic Cylinder/Titaniumhybrid Structure

Hybrid structures made of ceramics and metals form very efficient shield against projectiles sincethey combine the high hardness of ceramic with the ductility of metallic materials. It helps absorb theimpact energy from firearm-fired projectiles and shrapnel from explosions in order to protect lives.This paper demonstrates a design conceptand the criteria to select materials for a high resistant hybridstructure against multi-hit12.7mm armor-piercing projectile. Based on the analytical models andnumerical simulation, the failure mechanism of the target configurations has been discussed andsubsequently employed ballistic experiments for testing and verification. The main contents andinnovative work include:Based on the understanding of alumina ceramic and TC4material characteristics and interactionbetween projectile and target, a lightweight hybrid structure consisting of alumina ceramics pelletsand TC4was designed and prepared. The target area density of the armor panel was7.47g/cm2, and itsvolume density was3.2g/cm~3, which is a little higher than aluminum alloy. Due to the fact that splicedpieces of ceramic had protective blind area, the impact probability model was provided for the firsttime, which has important guiding significance for the design of the hybrid armor.The hybrid structure was tested by12.7mm armor-piercing projectile, whose protection capabilityarrived at Type III, Class2A according to the MIL-PRF-46103E norm; meanwhile, there was noexisting protective blind area in CC/TC4hybrid structure, and due to the projectile changing itsdirection by deflecting on the ceramic pellets facing, the ballistic resistance of the three pellets’interstitial site are much higher than a pellet’s central hit. The penetration process and mechanismofthe hybrid structure against different speed of projectile were investigated with3Dcommercial codeANSYS/LS-DYNA; bycomparing the numerical results withthe experiments, the results show that thenumerical results were well agreement with experiments on the highness deformation of TC4backlayer. It explained the debonding mechanism between CC pellets and TC4back plateusingone-dimensional stress wave theory.An analytical model was established to describe the hybrid structure under impact of deformableprojectile by assuming some hypotheses;meanwhile, the energy dissipation of the projectile is mainlyduring the Shock wave stage of impacting CC pellets.The projectile’s overlength produced analyticalresults that match fairly well with simulation results and ballistic experiments.