以准三维针刺炭纤维毡为预制体，采用化学气相渗透工艺在预制体中炭纤维／基体炭之间制备C-SiC-TaC-c复合界面，利用树脂浸渍一炭化工艺对材料进一步增密，获得含C-SiC-TaC-C界面的C／C复合材料。研究了1400-2500℃不同温度热处理前后复合材料的微观结构和力学性能。结果表明：热处理前，SiC-TaC界面为管状结构，复合材料的抗弯强度为241．6MPa，以脆性断裂为主；经1400-1800℃热处理后，TaC界面破坏呈颗粒状，复合材料的平均抗弯强度下降到238．9-226．1MPa，其断裂方式不变，但断裂位移由0．7mm增至1．0mm；经2000-2500℃热处理后，SiC、TaC界面均受到破坏，复合材料平均抗弯强度急剧下降至158．7-131．8MPa，断裂方式由脆性断裂转变为假塑性断裂。%C-SiC-TaC-C multi-interlayers were introduced in the carbon fiber/carbon matrix interface in quasi 3D needled carbon felt by chemical vapor infiltration, the modified C/C porous performs were densified by impregnation- carbonization processes to obtain C/C composites with C-SiC-TaC-C multi- interlayers. The microstructure and mechanical properties were studied after heat treatment （HTT） at different temperatures of 1400-2500℃. The results show that the SiC- TaC interlayers have a tubular structure before HTT; while the average flexural strength of the as-prepared composites is 241.6 MPa with a brittle fracture. After HTT at 1400-1800℃, TaC interlayer is damaged to granular structure; As a result, the flexural strength of the composites declines to 238.9-226.1 MPa also with a brittle fracture, but an increasing of fracture displacement from 0.7 mm to 1.0 mm. After HTT at 2000-2500℃, both SiC and TaC interlayer are damaged. The flexural strength sharply declines to 158.7-131.8 MPa with an obvious change of fracture behavior from brittleness to pseudo-ductility.
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