Evidence of optimal interfaces in bio-inspired ceramic-composite panels for superior ballistic protection

Ceramic-composite panels are acknowledged to provide effective impact protection even against small fragments and armour piercing projectiles. Nature shows similar solutions, coupling an hard face and soft backing layers, in dermal animal armours for protection against predators. Finite element simulations of impact on ceramic-composite panels, to evaluate their energy absorption capability, are presented. The influence of key parameters, like interface strength and friction, on ballistic limit is studied. We find that a proper set of interface parameters is able to maximize the specific energy absorption of the panel: although this optimum is variable case by case depending on projectile penetrability and target configuration, general guidelines are provided. Oblique impact results in a higher ballistic limit also thanks to projectile change in trajectory, providing interesting spots for future developments. Numerical results are compared with experimental data from literature and forecasts of analytical models.