Kevlar缝线捻度对缝合复合材料力学性能的影响

Effect of Twist Degree of Kevlar Stitch Threads on Mechanical Performance of Stitched Composites

缝合技术作为整体成型低成本制造技术已在航空领域得到广泛应用。缝合过程中使用的缝线需要加捻提高使用性能。缝线捻度对缝线自身的性能和缝合织物增强复合材料的力学性能均产生影响。本文以缝合中应用最多的Kevlar缝线为研究对象,通过实验研究不同捻度Kevlar缝线的渗透率和断裂强度,同时研究不同捻度缝线在链式和锁式两种不同缝合方式中对缝合复合材料拉伸性能、弯曲性能和层间剪切性能的影响。通过实验结果来确定缝合中使用的Kevlar缝线的最佳捻度。

The sticthing technique as the monolithic molding and low-cost manufacture technique has been widely applied in aeronautics. The stitch threads used in stitching process are needed to be twisted in order to improve the characteristic of service. The degree of the twist affects the sticth threads and the sticthed composites. The Kevlar stitch threads used popularly are studied here. The permeability and breaking strength of Kevlar stitch threads with diffetent degrees of twist are investigated experimentally,whilst the effect of Kevlar stitch threads are discussed with diffetent degrees of twist on the tensile property,bending property and interlaminar shear property of sticthed composites by chained stitching and locking-type stitching. The Kevlar stitch threads with the best degree of the twist are confirmed by the experimental results.