热氧老化对三维编织碳纤维-玻璃纤维/双马来酰亚胺树脂复合材料力学性能的影响

Influence of thermo-oxidative aging on the mechanical performance of threedimensional braided carbon fiber-glass fiber/bismaleimide composites

研究了三维编织碳纤维-玻璃纤维/双马来酰亚胺树脂复合材料和层合碳纤维-玻璃纤维/双马来酰亚胺树脂复合材料在200℃和250℃分别老化10、30、90、120和180天后的弯曲和剪切性能的变化。结果显示热氧环境下,纤维/双马来酰亚胺树脂基体界面性能随着老化时间的延长而显著下降,且编织复合材料老化后的弯曲和剪切性能保留率大于层合复合材料。这是由于编织复合材料中沿厚度方向的Z向纱将所有纱线捆绑为一个整体结构抵抗外力,且在热氧老化造成复合材料之间产生裂纹时,Z向纱的存在可以阻挡裂纹的扩展,减缓材料的老化速率。这说明与层合复合材料相比,编织复合材料的整体结构能够起到补偿由热氧老化导致的力学性能下降的作用。

The bending and shear properties of the three-dimensional braided carbon fiber-glass fiber/bismaleimide composite and the laminated carbon fiber-glass fiber/bismaleimide composite were investigated aging at 200℃and 250℃ for 10, 30, 90, 120, and 180 days, respectively. The results show that the interfacial performance of the fiber/matrix decreases significantly with the prolonged aging time in a hot oxygen environment, and the bending and shear retention rates of braided composite are better than the laminated composite. This is because Z-binder yarns in the thickness direction of braided composite bundle all yarns into an integral structure to resist external load, and the existence of Z-binder yarns can prevent the expansion of cracks and slow down the aging rate of composites when cracks occur between composites due to thermal-oxidative aging. This means that the integrated structure of braided composite can compensate the mechanical performance degradation caused by hot oxygen aging compared with the laminated composite.