超高分子量聚乙烯纤维平纹织物-单向布混合堆叠板的防弹机制

Ballistic mechanism of the hybrid panels with UHMWPE woven fabrics and UD laminates

柔性防弹衣具有隐蔽性好、穿着舒适的优点,而采用平纹与单向(UD)布杂化结构具有更好的防护效果。本文采用三层超高分子量聚乙烯(UHMWPE)纤维平纹织物(A)和两层Dyneema®SB51 UD布(B)组成AAABB和BBAAA两种混合靶板,通过弹道实验比较两种排列方式的防弹性能差异。结果表明,将平纹织物在前UD布在后能大幅提升整块板的防弹性能,能量吸收比后者高约20%。进一步采用有限元模拟来阐明其防弹机制,模拟结果表明将平纹织物放在面层不易被切断,使得平纹织物层发生更大的形变,也使后面的UD布发生大面积形变,吸收大量能量。而UD布放在前面层易产生的切力破坏,失去对后面层的作用。而平纹织物在后层容易发生滑移,且形变纵深过大,不利于防弹保护。该研究结果阐明了平纹织物和UD布不同顺序堆叠时的防弹机制,为进一步优化设计该类柔性防弹衣提供了坚实的理论基础。

Soft body amour has the advantages of good concealment and high comfortability.Recent studies demonstrate that soft body amours made up of layers of woven fabrics and unidirectional(UD)laminates show better ballistic performance.However,the mechanism behind has not been clarified.This work utilized three layers of woven fabrics(A)made by ultrahigh molecular weight polyethylene(UHMWPE)yarns and two layers of Dyneema®SB51 UD laminates(B)to compose two types of hybrid panels,viz.AAABB and BBAAA.Ballistic tests were carried out to evaluate their performance.The results show that the first type panel absorbs around 20%more energy than the second counterpart does.The finite element modelling is used to clarify the ballistic mechanism.The results illustrate that when the woven fabrics in front,they are not easier to be failed by shear,which results in more deformation of the fabric and therefore more deformation of the UD laminates behind,thereby giving rise to higher energy absorption.In contrast,when the UD laminates in front,they are easier to be damaged by the shear stress,failing to act on the followed layers.Moreover,when the woven fabrics at the rear,they tend to slip and meanwhile bring about more deformation in depth,which is detrimental to the protection.This study sheds light on the ballistic mechanism of hybrid panels with laying woven fabrics and UD laminates in different sequences.Such results,theoretically,pave the way for the design of the hybrid soft body amours.