Ballistic response of stitched woven fabrics with superior energy absorption capacity: Experimental and numerical investigation

Abstract

It has been widely accepted that yarn pull-out and windowing plays a vital role in absorbing impact energy in protective fabric systems. Stitching within the fabric was devised to constrain the transverse and lateral displacement of the primary yarns, using conventional cotton sewing threads. This paper reports the experimental and numerical methods and results of an investigation on the mechanisms that enable higher impact energy absorption of woven fabrics with designed yarn stitching. Penetration tests were performed over a range of impact velocities from the ballistic limit up to 180 m/s. The experimental results showed that the energy absorption of the stitched fabric sample was more than four times higher than that of the unstitched sample. For mass-normalized metrics, stitching the fabric on every other yarn yields a 146% improvement in energy absorption capacity when compared with the unstitched samples. Numerical predictions found that the more protective stitched samples enable enabling the fabric to absorb more strain and kinetic energy. It was also found that the stress concentration was greater on the primary yarns in the stitched samples, indicating the much higher likelihood of fiber failure rather than yarn pull-out such that that the rupture stress can be reached for the stitched samples.