摘要
通过改变预制体厚度方向密度及更换不同热膨胀系数的碳纤维来制备C/C复合材料,通过场发射扫描电子显微镜分析试样端面的微观形貌以及金相显微镜观察试样热解炭结构,进一步分析在相同沉积工艺下,变密度预制体对C/C复合材料沉积效率及其力学性能的影响。结果表明,厚度方向中间选择0.4 g/cm^(3),两侧选择0.35 g/cm^(3)制备P1试样沉积平均增密0.94 g/cm^(3);厚度方向中间选择24 k碳纤维,两侧选择12 K碳纤维制备的B2试样沉积平均增密为1.17 g/cm^(3)。B2试样综合性能最佳,致密化速率约0.04 g·cm^(-3)·h^(-1),整体密度均匀性较高,热解碳结构为光滑层和粗糙层混合结构,抗弯强度约为73.5 MPa。
C/C composites were fabricated by adjusting the density of preforms along the thickness direction and utilizing carbon fibers with different thermal expansion coefficients.Under identical needling and deposition processes,the micro⁃structural morphology of sample cross-sections was analyzed using field emission scanning electron microscopy,while pyro⁃lytic carbon structures were examined through metallographic microscopy(broussonetia papyrifera).This study further inves⁃tigates the influence of density-modified preforms on the deposition efficiency and performance of C/C composites.The re⁃sults show that the P1 samples were prepared with 0.4 g/cm^(3) of the thickness direction and 0.35 g/cm^(3) of both sides,and the P1 sample density was increased by 0.94 g/cm^(3).The B2 samples were prepared from 12 K fibers on both sides and 24 k fi⁃bers in the thickness direction,the B2 sample density was increased by 1.17 g/cm^(3).Moreover,the comprehensive perfor⁃mance of B2 sample is the best,the compaction rate is about 0.04 g·cm^(-3)·h^(-1),and the overall density uniformity is high.The pyrolysis carbon structure is a mixed structure of smooth layer and rough layer,and the bending strength is about 73.5 MPa.
作者
苟美博
苏超
强涛
GOU Meibo;SU Chao;QIANG Tao(School of Continuing Education,Xi'an Technological University,Xi'an 710072)
出处
《纤维复合材料》
2026年第1期30-36,共7页
Fiber Composites
关键词
密度
不同热膨胀系数
C/C复合材料
沉积速率
热解碳结构
density
thermal expansion coefficient
C/C composites
deposition rate
pyrolysis carbon structure
