采用聚对苯撑苯并嗯唑纤维(PBO)长丝缠绕增强碳纤维(CF)束,并通过真空辅助树脂转移成型法制备了环氧树脂/PBO-CF复合材料.采用三点弯曲试验法对包覆纤维增强复合材料的弯曲强度和弯曲模量进行了测试,并利用扫描电子显微镜观察材料的弯曲破坏模式,研究了包覆纤维对材料压缩破坏过程和界面性能的影响.结果表明,纤维包覆可以提升CF复合材料的弯曲强度,其中单向、双向旋转缠绕方式可分别提高20％、36％;三点弯曲的破坏都是在压缩面产生的,纤维包覆复合材料的破坏过程是由于一束纤维的整体压缩屈曲造成了破坏,而非单根纤维的屈曲破坏;PBO-CF和环氧树脂的界面性能较差,阻碍了长丝缠绕增强纤维束复合材料弯曲性能的进一步提升.%A type of CF bundle wound with PBO(Poly-p-phenylene benzobisoxazole) filament was designed,and than the epoxy composites with the CF bundles were prepared by vacuum assisted resin transfer molding (VARTM).The flexural strength and modulus of the PBO-CF/epoxy composites were evaluated by a three-point bending test method,the bending failure modes were observed by a scanning electron microscope.The influence of filament winding methods on the failure process was studied.The result indicated that filament winding could effectively improve the flexural strength of epoxy/CF composites.The composites achieved an increase in flexural strength by 20 ％ through the unidirectional rotation-winding method and an increase by 36 ％ through the bi-directional rotation-winding mode.The damages of three point bending were all observed on the compression surface.The failure process of filament-winding carbon fiberreinforced composites was resulted by the compressive yield of a single bundle rather than by a single fiber.Moreover the interfacial adhesion between the PBO-CF and epoxy matrix was poor,thus resulting in a limitation for the further improvement of flexural properties.
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