Yarn Pull-Out as a Mechanism for Dissipating Ballistic Impact Energy in Kevlar~(~R) KM-2 Fabric Part Ⅰ: Quasi-Static Characterization of Yarn Pull-Out

摘要

Yarn pull-out can be an important energy absorption mechanism during the ballistic impact of woven Kevlar~(~R) fabric. This study reports the effects of fabric length, number of yarns pulled, arrangement of yarns, and transverse tension on the force-displacement curves for yarn pull-out tests on Kevlar~(~R) KM-2 fabric under laboratory conditions. A semi-empirical model is presented for predicting the yarn pull-out force and energy as a function of pull-out distance, including both yarn uncrimping and subsequent yarn translation. This model is found to replicate the experimental data with a high degree of accuracy, and should prove useful for understanding ballistic experiments and improving computational modeling of fabrics.