Numerical investigations into the response of fabrics subjected to ballistic impact

Abstract

The use of high-performance fibres for ballistic protection has made it possible to produce lightweight soft body armour. This provides more mobility and comfort to body armour users such as soldiers and police officers. Efforts to design more protective body armour at a reduced weight have ever continued. Ballistic impact modelling, which provides an in-depth understanding of the energy absorption mechanism of ballistic fabrics, plays an important role in designing lightweight soft body armour. This paper reports the results of numerical investigations into the stress distribution and failure mode of ballistic fabrics subjected to high-velocity impact. Finite-element (FE) models were built up and used to predict the response of ballistic fabric systems. The research confirmed that the fabric is able to absorb more impact energy with enhanced yarn–yarn friction, indicating that, if by special weaving techniques of yarn–yarn friction increase, an improvement in ballistic performance might be expected. It was also predicted from the FE simulation that yarn–yarn friction not only influence the projectile engagement time with the fabric, but also plays an important role in stress distribution on the primary and the secondary yarns. In addition, theoretical prediction from a multi-ply fabric system showed that the front layers of fabric are more likely to be broken in shear, and the rear layers of fabric tend to fail in tension. This suggested that using shear resistant materials for the front layer and tensile resistant materials for the rear layer may improve the ballistic performance of fabric panels.