Degradation of yarns recovered from soft-armor targets subjected to multiple ballistic impacts

Post ballistic impact residual yarn mechanical properties were analyzed from two different as-received shoot packs composed solely of AuTx yarn possessing the 2/2 twill weave structure, one being impacted by 9-mm projectiles and the other by 2-grain projectiles. It was found that yarn mechanical properties from both shoot packs yielded similar results, regardless of yarn orientation, ply location, or penetrator size, which indicates that ballistic damage in the packets is very localized, producing little damage to the neighboring yarns. Mechanical properties of these woven, ballistically impacted, and then extracted yarns were compared to as-received native spooled AuTx yarn yielding a slight reduction in tensile strength, an increase in failure strain, and a reduction in elastic modulus, thereby yielding little variation in yarn toughness.