Numerical study on mechanisms of angle-plied panels for ballistic protection

This paper investigates on the mechanisms behind the angled ply-orientation on the ballistic performances of multi-ply UHMWPE fabric panels. Finite element (FE) models have been established for the 3-ply align-laid [0/0/0] and angle-laid [0/30/60] fabric panels. Numerical analyses on the time history of projectile energy loss and panel energy absorption, panel failure time, and the stress distributions at two representative velocities are carried out for these two panels. Study results show the existence of a critical velocity for the 3-ply fabric panels. Below this critical velocity, the enhanced inter-ply isotropy in the angle-laid panel contributes to the improved energy absorption, whereas above this critical velocity, the angle-laid panel is found prone to initial stress concentration, leading to yarn premature damage on the rear ply of the panel and thus the disappearance of the advantages of the angle-laid panel. This phenomenon is supported from the FE investigation as well as from the experimental results. [Display omitted] •Numerical yarn-level models of plain woven fabrics were built and experimentally validated.•3-Ply angle-laid panels were found with improved intra-ply isotropy through superimposition.•It is however prone to initial stress concentration.•The critical velocity for the 3-ply fabric panels was identified.•Beyond this velocity the advantage of the angle-laid panels over the align-laid disappeared.