【摘要】 采用等温化学气相渗透方法,通过调整沉积工艺,制备了具有不同微观组织结构的2D C/C复合材料.利用偏光显微镜(PLM)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)结合选区电子衍射(SAED),研究了热解炭基体微观组织结构,借助万能试验机测试了材料的三点弯曲性能.结果表明:层状高织构(HT)热解炭基体占优时C/C复合材料表现为假塑性断裂;扁平片状中织构(MT)热解炭与颗粒状各向同性层热解炭(ISO)有利于提高材料的弯曲强度;HT基体与炭纤维界面结合良好,界面处不存在非HT织构,但取向角(OA)略有增大.更多还原

【Abstract】 The 2D C/C composites with different microstructures were fabricated by isothermal-isobaric chemical vapor infiltration(ICVI).The mechanical properties of the 2D C/C composites were investigated by 3-point bending tests.The microstructures of the pyrocarbon matrix were observed by polarized light microscope(PLM),scanning electron microscope(SEM),transmission electron microscope(TEM) combining selected area electron diffraction(SAED).The results show that 2D C/C composites with dominant layered-HT pyrocarbon matrix exhibit a pseudo-plastic failure behavior.The flake-like fragments MT and granular-like particles ISO are in favor of increasing the flexural strength of the materials.It exists a good interfacial bonding between the fiber and HT layer.The non-HT layer does not exist at the interface,but the orientation angle(OA) of the matrix slightly increases.更多还原