【作者】 金利民；

【导师】 顾伯洪； 孙宝忠；

【作者基本信息】 东华大学 ， 纺织材料与纺织品设计， 2009， 硕士

【摘要】 双轴向经编针织物由三个系统的纱线组成,即经纱、纬纱与经编针织纱,其中经纱和纬纱互不交织而直接以0°/90°铺层排列,使织物和复合材料具有较高的面内刚度和强度;针织纱在厚度方向上对经纬纱起束缚作用,维持织物整体的结构稳定性,提高织物增强复合材料的断裂韧性和层间剪切强度。该织物形成的复合材料具有较高的面内刚度,冲击能量将以较高的应力波速扩展到复合材料的大面积区域。本论文主要工作是:(1)利用真空辅助树脂传递模压成型技术制造双轴向经编针织复合材料;(2)测试复合材料靶板的弹道冲击性能,得到在不同入射速度下弹体的剩余速度并考察复合材料破坏形态与破坏模式;(3)将经编针织纱的力学性能转化于基体,建立复合材料细观结构简化模型与弹道侵彻模型,结合商用有限元软件ABAQUS分析复合材料的弹道侵彻性能;(4)比较实验和有限元计算的结果,分析两者在弹体剩余速度、弹体动能吸收以及复合材料靶板破坏形态等方面的一致性和差异性并研究复合材料的破坏机理。本文研究为双轴向经编针织复合材料在弹道或高速冲击加载条件下的防护设计提供一种切实有效的预测方法。希望本工作可以应用于飞行器、高速车辆和弹道防护等工程领域的双轴向经编针织复合材料结构设计。更多还原

【Abstract】 Bi-axial warp-knitted (BWK) fabric is composed of three kinds of yarns, which including warp, weft and knitted yarns. The warp yarns and weft yarns are laid in 0°/90°order and not interlaced each other. The non-crimp warp yarns and weft yarns will induce the higher in-plane stiffness and strength compared with other fabric structures. The knitted yarn loops (tricot yarns) hold the warp and weft yarns together. They maintain the fabric structure stability. The BWK fabric reinforced composite has high in-plane stiffness. The impact energy will propagate to the large area of the composite plate with stress wave propagation speed.The main researches conducted are as follows:(1) Manufacturing bi-axial warp-knitted composite with vacuum assisted resin transfer molding (VARTM) technique. (2) Ballistic tests of the BWK composite plates. The residual velocities of projectile under different strike velocities were measured. The impact damage morphologies and mode of the BWK composite were investigated and discussed. (3) A simplified micro-structural model of the BWK composite was established which converted stiffness and strength of knitted yarn loops to matrix. Incorporated with commercial-available FEM software package ABAQUS, the ballistic penetration of the BWK composite was calculated. (4) The residual velocities, kinetic energies of projectile were compared between experimental and FEA results. The impact damages of the BWK composite were also compared for elucidating the failure mechanisms.This paper provides an effective prediction method for designing the protective structure of the BWK composite. We hope such an effect could be applied to the structural design of the BWK composites in the field of aircrafts, high speed vehicles and ballistic protections.更多还原