Effects of water on the ballistic performance of para-aramid fabrics: three different projectiles

In this paper, the effects of water on the ballistic performance of the para-aramid fabrics were investigated through three typical projectiles (1.1 g FSP, 9 mm FMJ and 7.62 mm TYPE51). Three different aramid fabrics made up of Taparan 629 fiber or Kevlar 129 fiber were shot by these projectiles in both dry and wet conditions according to ballistic limited velocity V50 testing method (MIL-STD-662 F). Pull-out testing, water absorption, static contact angle, and failure mode of the fabrics were performed to study the possible ballistic mechanisms. The results reveal that the V50 values of three aramid fabrics all decrease after immersion in water, even the fabric has been treated with water-repellent finishing. The V50 values of aramid fabrics in wet state is affected by water absorption of fabric, yarns friction and bullet types. And, the slippage of yarns is a dominant mechanisms affected on ballistic performance of aramid fabric in wet condition. The lower water absorption and higher friction between the yarns can improve the ballistic performance of aramid fabrics.