On analysis of deformation and damage mechanisms of DYNEEMA composite under ballistic impact

This paper deals with the assessment of damages occurred to an Ultra-High Molecular Weight Polyethylene (UHMWPE) based composite during ballistic impacts with two bi-metallic projectiles of different morphologies and masses. More specifically, the evaluated composite is DYNEEMA® HB80. The conditions of impact aim at evaluating the behind armour blunt trauma effects (BABT) of blocks of ballistic gelatine covered by the composite protection. The evaluated cases correspond to non-perforating impacts of the composite. The microstructure of the intact composite is precisely described. The damaged plates are compared to evaluate the influence of the projectile nature and to verify the influence of their kinetic energy on the displacement, deformations and damage mechanisms of the composite plate. Post-mortem analyses of the composite with incrusted projectiles are performed. Also, because the dynamic interaction process between the projectiles and armour plates was not visible, numerical simulations were conducted with LS-DYNA®. Overall, a good correlation was obtained between the tests and the models. An evaluation of the kinetic energy dissipation was also performed.