Study on Z-pin enhancement technology with low in-plane damage

doi:10.19936/j.cnki.2096-8000.20211128.010

Abstract

Abstract: This article presents an experimental investigation on the efficiency of the Z-pin pre-hole insertion process in reducing the in-plane damage while improving the delamination resistance of carbon fibre/epoxy laminates. The results show that the Z-pin pre-hole insertion process could reduce the fiber crimp, flow dilution and fracture. Specifically, the tensile strength and flexural strength of the laminates reinforced with Z-pin(0.28 mm in-diameter) were only reduced by 3.02% and 3.33%, respectively. It shows that Z-pin pre-hole insertion process could significantly reduce the in-plane damage of Z-pinned laminates. Furthermore, the tensile strength and flexural strength of the laminates reinforced with Z-pin(0.18 mm in-diameter) were only decreased by 1.69% and 1.12%, respectively. It shows that fine Z-pin could further reduce the in-plane damage of Z-pinned laminates while achieving interlaminar toughening. In addition, through the analysis of the failure mechanism of Z-pinned laminates, it is concluded that the in-plane damage of the laminates could be reduced by reasonably setting the arrangement of Z-pin, using fine Z-pin and reducing the use of 0° ply in design of layer.

Key words: Z-pin, composite, tensile properties, flexural properties, low-damage

CLC Number:

TB332

YAN Bin, LI Xiang-qian, YIN Ming-xin, LIU Wei-wei, CHEN Wei, MA Cheng-yan. Study on Z-pin enhancement technology with low in-plane damage[J]. COMPOSITES SCIENCE AND ENGINEERING, 2021, 0(11): 62-68.

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