以高导热沥青基炭纤维布为增强体，中间相沥青为黏结剂，采用热模压成型及液相浸渍裂解工艺增密，并经高温石墨化处理制备二维高导热炭/炭复合材料。利用X射线衍射仪和透射电子显微镜对经不同温度处理后的沥青基炭纤维及二维高导热炭/炭复合材料的结构和形貌变化进行表征，并考察石墨化处理温度对复合材料热导率的影响。结果表明，随着热处理温度的升高，纤维及复合材料内部石墨微晶尺寸增大、取向度变好，纤维与基体间界面结合紧密、裂纹减少，而基体碳层间裂纹则呈扩大趋势。此外，二维高导热炭/炭复合材料的热导率随热处理温度的升高而线性增加，经3000℃处理后，材料热导率高达443 W/m·K。
High thermal conductivity carbon/carbon composites ( HTC-C/Cs) have a high specific modulus and a low thermal ex-pansion in addition to all the excellent properties of traditional C/C composites, which have been a research focus in recent years. 2D HTC-C/Cs were prepared by hot pressure molding, densification by precursor impregnation and pyrolysis, and then heat treat-ment at high temperatures, using pitch-based carbon fiber fabric with a high thermal conductivity as reinforcement and mesophase pitch as the binder precursor. The structure and morphology of pitch-based carbon fibers and 2D HTC-C/Cs were investigated by XRD, SEM and TEM. The thermal conductivity was measured by laser-flash diffusivity. Results show that with increasing heat treatment temperature the crystallite size increases, the degree of order is improved, the thickness of laminar graphite around the car-bon fibers increases, and the number of interfacial cracks between the fiber and matrix decrease and cracks between matrix layers are expanded. A linear relationship between thermal conductivity and heat treatment temperature was observed and the highest thermal conductivity was 443 W/m·K after heat treatment at 3 000℃.
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