【摘要】 以缝合结构织物为预制体,采用化学气相沉积工艺制备了C/C复合材料。通过OM、PLM对其组织进行了分析。采用SEM观察了热处理前后试样的断口形貌。结果表明:该复合材料组织为粗糙层热解碳,主要沉积在纤维束内的小孔隙内;热解碳与纤维之间界面结合紧密,沉积态C/C复合材料表现为脆性断裂方式,断口较平整,主要为纤维束的断裂;热处理后纤维/基体界面结合变弱,有单根纤维的拔出,材料呈假塑性断裂方式。更多还原

【Abstract】 By using stitched fabric as the preform,carbon/carbon composites were prepared by chemical vapor infiltration.The microstructures of the stitched carbon/carbon composites were analyzed by optical microscope(OM) and polarized light microscope(PLM).The fracture surfaces were observed by scanning electron microscope(SEM) before and after high temperature heat treatment(HTT).The results show that the as-deposited carbon/carbon composites consisted of rough laminar(RL) pyrocarbon which mainly deposited in the small porosities between the fiber bundles.As-deposited composites fail in the brittle fracture with a flat fracture surface and fractured fiber bundles because of the strong bond of pyrocarbon and fiber.After HTT,the bond between fiber and matrix becomes weak,composites shows the single fiber pulling-out and a pseudo-plastic mode.更多还原