Effects of fabric construction and shear thickening fluid on yarn pull-out from high-performance fabrics

Yarn pull-out is one of the major modes of fabric failure during an event of impact. In this article, the effects of weave and fabric sett on yarn pull-out force have been investigated for untreated and shear thickening fluid (STF) treated p-aramid fabrics. Further, the effect of different fluid treatments on yarn pull-out behavior has been analyzed using p-aramid and ultra-high molecular weight polyethylene (UHMWPE) fabrics. For all levels of fabric sett, plain woven fabrics exhibited higher yarn pull-out force compared to twill, matt and satin weaves. STF impregnation increased the yarn pull-out force considerably for p-aramid and UHMWPE fabrics and this was found for all the weaves in the case of the former. However, increase in fabric sett beyond a threshold level caused yarn breakage before yarn pull-out in case of STF-treated plain woven p-aramid fabrics. Yarn pull-out force was found to have good association with the energy absorption by the high-performance fabrics during low-velocity impact (6 m s(-1)). The normalized yarn pull-out force was higher for two consecutive yarns than for two yarns with a single gap.