本文用透射电子显微术研究了三向碳-碳复合材料的界面结构。结果表明:在碳纤维表面微缺陷区或活性区,存在沉积碳微晶条带“钉扎”结构;在碳纤维表面光滑区,存在一定数量的界面间隙:沥青碳与沉积碳的界面存在一个沉积碳微晶条带与沥青碳石墨条带相互贯穿网络所形成的诱导结构界面相。本文分析了界面缺陷,并讨论了界面结构对纤维束断裂行为的影响。 In this paper, the interfacial structure of three-dimensional carbon-carbon composites was investigated by transmission electron microscopy. The results show that there exists “pinning” structure of carbon microcrystalline strip in the micro-defect area or active area on carbon fiber surface; there is a certain amount of interfacial clearance in the smooth area of ​​carbon fiber: there is a deposit of carbon on the interface of pitch carbon and deposit carbon The microcrystalline strip and the bitumen carbon-graphite strip penetrate each other through the network to form the induced structure interface phase. This paper analyzes the interface defects and discusses the influence of interface structure on the fracture behavior of fiber bundles.