碳纤维增强环氧Z-pin拔脱性能

 为了研究Z-pin层间增强的影响因素,采用Z-pin-浇注体拔脱实验分析了Z-pin埋入深度、直径和固化度对其拔脱性能的影响。采用Z-pin-浇注体与层合板的对比拔脱实验验证了Z-pin-浇注体拔脱实验表征Z-pin与被增强体的结合状态的可行性。Z-pin-浇注体拔脱实验结果表明,Z-pin的最大拔脱力随着埋入深度的增加而非线性增加;直径对拔脱力的影响主要体现在总接触面积的改变,最大拔脱力与Z-pin直径呈线性关系,其中直径0.7 mm Z-pin的最大拔脱力是直径0.3 mm Z-pin的2.35倍;控制Z-pin固化度,利用其与基体的共固化效应可以大幅地提高界面剪切强度,失效模式从界面脱粘转变成界面脱粘和基体树脂的内聚破坏的混合模式,最大拔脱力最高可以提高17倍。

Pullout performance of carbon fiber/epoxy Z-pins

In order to study the influencing factors of Z-pin''s interlaminar reinforcement, the Z-pin pullout experiment from poured body is used to analyze the influence of the Z-pin''s embedded length, diameter and curing degree on the pullout performance. And the behavior of Z-pin being pulled out from laminates is compared to that from poured body to verify the feasibility of Z-pin pullout experiment characterizing the bonding condition. The results reveal that the maximum pullout force increased with the embedded length; the increase of Z-pin diameter contributed a linear rise to the maximum pullout force by enlarging the total contact area. The maximum pullout force of Ø0.7 mm Z-pin has jumped to 2.35 times that of Ø0.3 mm Z-pin. Furthermore, Z-pin''s co-curing with the matrix resin could improve the interfacial shear strength, and the failure mechanism is changed from interfacial debonding to a combination of cohesive failure of matrix resin and the interfacial debonding. The consequent elevation of maximum pullout force could be up to 17 times.