Abstract

Surface coatings on the fabrics can enhance protective properties of flexible body armors. It is known that the application of coating increases inter yarn friction, however, detailed mechanism of knife-yarn interaction in coated and uncoated fabrics is not fully understood yet. This study investigates in detail the knife-yarn interaction at individual yarn level and role of improved inter yarn friction in enhanced stab resistance of woven aramid fabrics deposited with SiO₂ coating. The coated fabric exhibited an increase of 115% in the knife penetration resistance compared with uncoated fabric due to increase in inter yarn friction. The coefficient of friction increased 29% after coating. The video graphicanalysis performed during quasi static stab resistance revealed important insights into the knife to yarn interactions. The filaments within the yarn in the uncoated fabric interact individually with the knife, undergo sequential cutting of filaments and offer less resistance to knife penetration. On the other hand, filaments within the yarn in the coated fabric were found to interact collectively, as cohesive assembly of fibers, undergo simultaneous cutting offering greater resistance to the penetrating knife. The results of yarn pull out, yarn sliding, single yarn cut resistance and single yarn strength tests confirmed that improvement in the stab resistance was attributed mainly to the increased inter yarn friction after coating the fabric while intrinsic properties of the yarn were not altered. The findings of this study will be helpful in the development of protective clothing with improved stab resistance.

摘要

织物上的表面涂层可以增强柔性防弹衣的保护性能。众所周知，涂层的应用会增加纱线间的摩擦，然而，涂层和未涂层​​织物中刀纱相互作用的详细机制尚不完全清楚。本研究详细研究了单根纱线水平的刀纱相互作用以及改进的纱线间摩擦在增强 SiO _{2沉积的芳纶机织织物的抗刺性中的作用}涂层。由于纱线间摩擦的增加，涂层织物与未涂层织物相比，其耐刀穿透性提高了 115%。涂层后摩擦系数增加了29%。在准静态防刺过程中进行的视频图形分析揭示了对刀具与纱线相互作用的重要见解。未涂层织物中纱线中的长丝单独与刀具相互作用，对长丝进行连续切割，并且对刀具穿透的阻力较小。另一方面，发现涂层织物中纱线内的细丝共同相互作用，因为纤维的内聚组装同时进行切割，从而为穿透刀提供更大的阻力。纱线拔出、纱线滑动的结果，单纱抗切割性和单纱强度测试证实，抗刺性能的提高主要归因于涂层织物后纱线间摩擦力的增加，而纱线的内在性能没有改变。这项研究的结果将有助于开发具有改进的防刺能力的防护服。