Ballistic Performance and Damage Evolution of Twaron Ct 737 Para-Aramid Composite Panels Under 9 × 19 Mm FMJ Loading

This study examines the mechanical behaviour and ballistic performance of Twaron CT 737 para-aramid/epoxy laminates manufactured by vacuum-assisted resin transfer moulding, with particular emphasis on damage development across different structural scales. Tensile, three-point flexural, and Shore D hardness tests were complemented by ballistic experiments using 9 × 19 mm full metal jacket (FMJ) ammunition. The composite achieved a mean tensile strength of 583.1 MPa, a flexural strength of 223.4 MPa, and a Shore D hardness of 87.9. A 24-layer panel with a nominal thickness of 14.2 mm prevented complete perforation during three consecutive impacts at a mean velocity of 399.3 m/s and a mean kinetic energy of 637.7 J. Scanning electron microscopy identified yarn pull-out, fibre fracture, fibrillation, and localized fibre–matrix separation, whereas X-ray computed tomography revealed internal deformation and interlaminar delamination extending through several reinforcement layers. These observations indicate that projectile arrest was accompanied by interacting fibre-scale and interlaminar damage processes within the woven architecture. The findings provide an experimental basis for understanding the ballistic response of multilayer para-aramid/epoxy composites under the investigated loading conditions.