Carbon fiber bundles with different distance and fiber content were punctured to form carbon fiber preforms. The pre⁃forms were densified by CVI and pitch impregnation⁃high pressure carbonization process. The results show that the material punc⁃tured by 12 K bundles with a distance of 2.1 mm displays tensile strength of 131.4 MPa along Z⁃direction and 111.3 MPa along XY⁃direction. With the bundle distance decreasing and the fiber amount of punctured bundle increasing,increase of the Z⁃directional carbon fiber volume result in increasing tensile strength along Z⁃direction obviously. The tensile strength under vacuum and 1 800℃ condition is similar to that under room temperature;the tensile modulus is lower and the tensile elongation is higher than that un⁃der room temperature. The tensile fracture surface of sample tested at room temperature is flat and smooth;there are obvious cracks in the interface between fiber and matrix. On the contrary,the tensile fracture surface of the sample tested at 1800℃ is rough,both the fibers and matrix fracture surface are rough,which present pseudoplastic characters.%采用不同间距、不同根数的纤维束穿刺成型炭纤维预制体，经进一步化学气相沉积、沥青浸渍⁃高压炭化致密制备穿刺C／C复合材料。拉伸性能测试结果表明，穿刺间距2．1 mm、穿刺束纤维根数为12 K的C／C复合材料获得高的拉伸强度，Z向拉伸强度131．4 MPa，XY向拉伸强度111．3 MPa；随着穿刺间距减小、穿刺丝束纤维根数增加，Z向纤维含量增加，Z向拉伸强度明显提高。穿刺C／C复合材料1800℃真空条件下的拉伸强度与室温相当，拉伸模量低于室温，延伸率高于室温；常温拉伸断口较平整，且纤维／基体间的裂纹明显，而高温拉伸断口参差不齐，纤维及基体断面粗糙，呈现出假塑性断裂特征。
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