The response of natural fibre composites to ballistic impact by fragment simulating projectiles

While plenty of work has been published on ballistic properties of high performance fibres such as ultra high molecular weight polyethylene (UHMWPE) and aramid, and their composites, literature on the ballistic impact potential of natural fibre composites is almost non-existent. In this paper, the ballistic properties of flax, hemp and jute fabric reinforced polypropylene composites processed by hot compression moulding are investigated. The composites’ ballistic limit (V50) was determined by subjecting the material to ballistic impact loading by fragment simulating projectiles (FSPs) using a block manometric cannon interchangeable (BMCI) gun. The composites’ ballistic effect was further examined by investigating the ballistic limit of composite-steel hybrid systems prepared by gluing thin mild steel plates on the face and rear of the natural fibre composites. Flax composites exhibited better energy absorption than hemp and jute composites. The composites failed by shear cut-out, delamination and fibre fracture. It was found that the ballistic properties of the hemp composites increased significantly when a mild steel plate was used as facing and backing.