Aramid/epoxy composites with angle-laid reinforcement constructions for ballistic protection

This paper investigates the ballistic impact mechanism of multi-ply aramid/epoxy composites with different laying up structures. Ballistic impact behaviour of the composites was evaluated by their energy absorption capacity and high-speed video observation and analysis. Plain woven aramid fabrics were used as reinforcements and the Seemann composites resin infusion moulding process (STRIMP) was employed for manufacturing composites with ARALDITE LY 564 epoxy matrix in this study. Angle-laid dry fabric assembles were used as reinforcements in parallel to the align-laid fabric assemblies. The energy loss during penetration process was used to characterise the ballistic performance of the composites experimentally. The results of the investigation indicate that for three-layered composites, [0/45/0] and [0/30/60] angle-laid constructions absorb 3% and 10% more energy than the composite with align-laid reinforcement. However, for the four-layered composites, angle-laid composites demonstrate lower ballistic resistance than the align-laid composites, which calls for further investigation.