中文摘要：

通过化学气相沉积（CVI）和化学气相沉积与先驱体转化结合（CVI＋PIP）的方法,制备了三种不同炭基组织结构的炭/炭复合材料。三种基体分别是光滑层基体（SLC）、粗糙层基体（RLC）和混合双基体（DMC）（过度生长锥基体＋呋喃树脂炭基体）。对这三种复合材料样品进行微观组织结构和动态力学性能表征。结果表明,内耗主要来源于炭基体缺陷的运动、纤维/基体界面的滑移和炭平面的滑移。复合材料的内耗对于温度和振幅变化非常敏感,但频率的变化对复合材料的的内耗影响不大。混合双基体具有最高的缺陷密度和最高的内耗,粗糙层基体具备较完美的炭平面和最低的内耗。炭基体的微观组织结构是影响内耗的关键因素,由于光滑层基体、粗糙层基体和混合双基体的微观结构的区别,导致在不同基体中出现了不同的内耗行为。在室温状态下,基体中缺陷和纤维/基体的界面的运动可能是影响内耗的主要因素,随着温度的升高,内耗的贡献可能主要来源于炭平面的滑移,而且我们还发现动态模量与缺陷密度存在一定关联。

英文摘要：

Three carbon/carbon composites with rough laminar,smooth laminar and dual matrix carbon were prepared by chemical vapor infiltration（ CVI） using hydrogen-diluted methane,CVI using nitrogen-diluted propane,and two-step CVI using first methane/hydrogen and carbon dioxideand then furan resin impregnation and carbonization. The influence of the microstructure of the carbon matrix on the internal friction behavior of the composites was investigated.Results indicate that the microstructure of the carbon matrix plays an important role in the internal friction. The overall internal friction is related to the motion of dislocations,the sliding of the fiber/matrix interface and the sliding of the carbon planes.The internal friction of the composite is very sensitive to temperature and amplitude,but less sensitive to frequency.Among these composites,the dual matrix carbon has the highest density of crystal-defects and the highest internal friction while the rough laminar carbon has perfect carbon planes and the lowest internal friction.