中文摘要：

采用碳纳米管膜作为碳纤维／环氧树脂复合材料的层间改性材料，应用液态成型树脂传递模塑工艺制备了碳纳米管膜／碳纤维／环氧树脂混杂复合材料，利用I型层间韧性与Ⅱ型层间韧性表达了其韧性相关性能，并分析了改性机理．碳纳米管膜在混杂复合材料层间仍然保持其原有连续网格结构形式，这种形式对张开型I型层间断裂韧性没有明显的改性作用，但对于滑移型Ⅱ型层间断裂韧性具有显著的改性效果．碳纳米管膜／碳纤维／环氧树脂混杂复合材料的Ⅱ型层间断裂韧性从碳纤维／环氧树脂复合材料的1292J／m^2提高到了2869J／m^2，提高了120％．材料微观形貌分析表明，这种由碳纳米管相互交叠、缠结而形成的网络结构有效地阻碍了层间微裂纹的扩展．

英文摘要：

Carbon nanotube film （CNTF） interlayer toughened carbon fiber （CF） reinforced epoxy resin （EP） hybrid composites were fabricated via resin transfer molding （RTM） processing in this paper. Multi- walled carbon nanotubes were prepared by chemical vapour deposition, and carbon nanobute films were prepared through vacuum filtration. Model I interlaminar fracture toughness GIc of laminates and model II interlaminar fracture toughness GIIc of laminates are used to characterize the fracture toughness of the RTM laminates. Furthermore,the toughening mechanism is discussed through microstructure of the fracture surface combining mechanical properties. The compact degree of the carbon nanotube films was influenced by the ratio of the multi-walled carbon nanotubes,whieh led to different impregnation of the carbon nanobute films to the epoxy resin. Experimental results indicated that the carbon nanotube films from carbon nanotubes of large aspect ratios exhibited better impregnation effect than those films from carbon nanotubes of small aspect ratios. The carbon nanotube films intercalated in the interlayer of the composites between the carbon fiber and the matrix resin as a whole laminated structure, and they still kept a continuous grid structure in the CNTF/CF/EP hybrid composites. As to the model I interlaminar fracture toughness GIc of laminates,the carbon nanotube films have no obvious improvement on the GIc value. However, the carbon nanotube films laid between the carbon fiber layers changed the failure mode of the CF/EP composites, leading to increased initial failure load and breaking load. As to model Ⅱ interlaminar fracture toughness GIIc of laminates, experimental results exhibited that the reinforcing efficacy on the sliding mode shear failure was remarkably increased for the CNTF/CF/EP hybrid composites. Model II interlaminar fracture toughness GIIc of laminates has increased from 1292 J/m^2 of the CF/EP to 2869 J/m^2 of the CNTF/CF/EP hybrid composites. There is 120% amplification in GIIc te