Ballistic performance and thickness optimization of TC4/UHMWPE laminates composite structure under high-speed impact

Fiber metal laminates have emerged as a promising solution for composite armor systems, addressing the growing demand for lightweight defense. A finite element model of TC4/UHMWPE laminates composite structure subjected to rigid projectile impacts was established to investigate the effects of material arrangement on ballistic performance. Response surface methodology was employed to develop a statistical model, followed by thickness optimization using Genetic Algorithm, with subsequent comparative analysis of the optimization results. The efficient global optimization framework, which couples GA with RSM, maximizes specific energy absorption while ensuring adequate ballistic performance, thereby achieving the objective of lightweight design. The findings indicate that under high-velocity impact, UHMWPE laminates experience localized shear failure, tensile deformation, and interlayer debonding, leading to delamination. The titanium alloy layer undergoes shear failure and forms plastic deformation zones. The titanium alloy backplate fails via perforation, resulting in petal-like fractures on the rear surface. The 9U2T5U2T structure with UHMWPE as the front plate and TC4 titanium alloy as the back plate, alternating between these materials, offers superior ballistic resistance and minimal rear bulge. The thickness of UHMWPE significantly influences specific energy absorption (SEA), while TC4 thickness governs ballistic resistance. The optimized TC4/UHMWPE laminates exhibit a significant enhancement in energy absorption capacity in the third UHMWPE layer, achieving a 7.7 % increase in SEA along with an 8.2 % reduction in mass.