Finite element analysis of pre-stretch effects on ballistic impact performance of woven fabrics

Pre-stretch effects on ballistic impact performance of woven fabrics that made of Kevlar KM2 is investigated with finite element simulation. Individual yarns of the fabrics are modeled with truss elements incorporated with equivalent material properties of real fiber yarns. Before the projectile is issued, a fabric panel that has a rectangular configuration is pre-stretched by directly applying displacement boundary conditions. This two-step loading condition is realized through results transferring capability offered by the commercial software ABAQUS. Simulation results reveal that pre-stretch can significantly influence the fabric's ballistic response such as ballistic limit, energy absorption and wave propagation. The fabric with higher pre-stretch absorbs more energy, however fails earlier than the fabric with lower pre-stretch. Parametric studies show that with the increase of pre-stretch, the deformation contour evolves from a pyramid shape that is conventionally observed in non-pre-stretched fabrics into a conical shape.