Validating the Critical Areal Density for a New Ballistic Armor Exhibiting Blunt Trauma Reduction

Abstract

Today there are several armor technologies for reducing penetration injuries. Some of the best technologies are light weight, but alone the trauma to the wearer remains significant. The areal density of a new Hybrid Composite Armor (HCA) maintaining compliance with level III NIJ 0101.06 standards was evaluated using ballistic testing and FEM. This new HCA has a multilayered composite design tailored for Behind Armor Blunt Trauma (BABT) reduction. Three areal densities of HCA were ballistic tested using 7.62 FMJ Lead Core projectiles and measurements of Back Face Signature (BFS) and V50 velocities were collected. For comparison, baseline monolith inserts of similar areal densities were also tested. A critical areal density was found to qualify for the standard while demonstrating a 29.4% reduction in BFS (and hence BABT) in comparison to its baseline. This armor design showed the greatest known propensity to reduce injury both due to the light weight and improved trauma performance compared to existing commercial designs. Numerical simulations in finite element code were carried out to validate with the experimental results. A method for evaluating change-in-velocity and volumetric stress distribution plots was presented using a mock HCA-P2 model. In the future, a similar FEA scheme can be used for predicting the ballistic limit and estimating improvements possible in BABT reduction for HCA concepts with relative design changes.