EFFECT OF Z-PIN IMPLANTATION ON FLEXURAL PROPERTIES OF CARBON FIBER/EPOXY LAMINATES

doi:10.19936/j.cnki.2096-8000.20210328.014

Abstract

Abstract: This essay presents knowledge that the effect of material, diameter and twisting state of Z-pin on the flexural performance of Z-pin reinforced composite laminates,which was studied through three-point bending test. The results show that the flexural strength and modulus of the carbon fiber Z-pin group specimens have been increased by 20.28% and 27.55%, respectively, compared with the blank groups without Z-pin, and the improvement effect is better than that of the polyimide fiber Z-pin group. The flexural strength and modulus of small diameter Z-pin group specimens have been increased by 19.96% and 29.32%, respectively, compared with the blank groups without Z-pin, and the boost effect is better than that of the large-diameter Z-pin group. While the twisted state of Z-pin has little effect on the flexural performance, which is related to the mixed failure mode combined pullout with shear failure. After Z-pin is implanted into the test piece, it significantly improves the flexural strain energy of the test piece. In the test, the flexural strain energy of Z-pin reinforced specimens increased by 15.23%~112.23% compared with the blank groups without Z-pin. Among them, the effect of large diameter Z-pin is the most significant, and the lifting ratio is more than 110%. In addition, Z-pin implantation can increase the resistance of specimens to deformation damage, and make the specimens show greater failure displacement. But, the specimens with low flexural strain energy are not easy to form stable damage propagation.

Key words: Z-pin, flexural properties, bridging effect, flexural strain energy, composites

CLC Number:

TB332

YAN Bin, CHEN Wei, MA Cheng-yan, TENG Xue-bei, LIU Wei-wei, LI Xiang-qian. EFFECT OF Z-PIN IMPLANTATION ON FLEXURAL PROPERTIES OF CARBON FIBER/EPOXY LAMINATES[J]. COMPOSITES SCIENCE AND ENGINEERING, 2021, 0(3): 88-92.

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