3 - Nonwoven and crossplied ballistic materials

Abstract

Although numerous methods have existed for decades to produce fiber-based material structures within the broad category known as “nonwovens”, not all of these are of practical use for ballistic resistant structures. The filament lay-up composite, or those structures made by parallel lay and resin reinforcement occupy an increasingly important sector of the ballistic resistant materials spectrum. These structures are designed to engage an incoming projectile with a much larger population of high strength fibers than can utilized with a woven or knitted fabric. The presence of a reinforcing resin also assists in the energy dissipation and the composite structure together acts to strip a bullet of its casing and flatten it upon impact. Staple fibers have not traditionally been used in ballistic resistant nonwoven structures because of their discrete, discontinuous character, but if formed together correctly, they can offer structural isotropy that filaments cannot.