Determination of stick-slip stage of single and multiple yarn ends pull-out in para-aramid (Kevlar®) woven fabric

The aim of this study was to understand the stick-slip properties of para-aramid woven fabrics. For this reasons, pull-out test was conducted on para-aramid Kevlar (R) 29 and Kevlar (R) 129 woven fabrics. The force-displacement curve from each fabric sample was obtained. The stick-slip region and accumulative retraction force region were defined based on the force-displacement curve. It was found that stick-slip and accumulative retraction forces depend on fabric density and the number of pulled ends in the fabric. Stick-slip and accumulative retraction forces in the multiple yarn pull-out test were higher than those of the single yarn pull-out test. Stick-slip and accumulative retraction forces in single and multiple yarn pull-out tests in the dense K29 fabric were higher than those of the loose K129 fabric. In addition, long fabric samples showed high stick-slip force compared to that of the short fabric samples.