Impact response of aluminum/rubber/kevlar hybrid multi-layers: experimental and numerical assessment

This study investigates the effectiveness of individual rubber and fabric Kevlar layers in enhancing the performance of an aluminum layer under high-velocity projectile impact. A combined experimental and numerical approach was employed to analyze the behavior of a hybrid multilayer ballistic shield. Four specimen configurations were tested: a thin aluminum layer, an aluminum/rubber bilayer, a stacked aluminum/rubber/Kevlar multilayer, and a spaced aluminum/rubber/Kevlar multilayer. A light gas gun apparatus was used to launch a 9.32 g projectile at an impact velocity of 165 m/s, with residual velocities measured using a high-speed camera. The results demonstrate that the addition of a thin rubber layer to the aluminum sheet increased the ballistic limit by 60.4%. Furthermore, incorporating Kevlar fabric into the hybrid panel improved the ballistic limit by 9.96%, while introducing a 15 mm spacing between Kevlar fabric and the bilayer enhanced the ballistic limit by 34.29% compared to the bilayer configuration. Finite element analysis (FEA) was conducted using LS-DYNA software to simulate the ballistic behavior and failure mechanisms during projectile penetration. A comprehensive parametric study was performed on the validated model, and the results are discussed in detail.