Effect of yarns in multiple directions on impact resistance of aramid/epoxy composites

In order to study the arrangements of yarns on the impact resistance of aramid/epoxy resin composites better, 0 degrees/90 degrees/0 degrees/90 degrees is the basic control group. In addition, three different arrangements are adopted for yarn laying, and the structures are 0 degrees/90 degrees/-45 degrees/45 degrees, 90 degrees/45 degrees/-45 degrees/0 degrees, -45 degrees/0 degrees/90 degrees/45 degrees respectively. In this paper, the interfacial bonding strength of composite materials is tested by yarn pull-out test. Drop hammer impact test is used to observe the impact resistance of composite materials; scanning electron microscopy was used for characterization to investigate the damage mechanism of fiber. The results show that aramid fiber/epoxy resin composites with yarn arrangement order of 90 degrees/45 degrees/-45 degrees/0 degrees have better impact resistance. And its energy absorption is obvious, with a peak value of 5.6 J, which is larger than other structures. In addition, the bonding force and damage mechanisms of internal interfaces of four kinds of aramid/epoxy composites under impact load are analyzed. The same time is taken as the unified variable to judge their respective advantages and disadvantages. The morphology of microscopic damage is used as the basis for judgment, which provides references for the engineering application of materials in structure.

Automated summary

Through studying the different yarn arrangements of aramid/epoxy resin composites, it is found that the composite with a yarn arrangement order of 90 degrees/45 degrees/-45 degrees/0 degrees has better impact resistance and energy absorption capacity.