摘要
利用三维编织炭纤维预制件通过先驱体浸渍裂解法制备C/SiC复合材料。研究了热解碳(PyC) /SiC界面相对复合材料的微观结构和力学性能的影响。弯曲性能通过三点弯曲法测试,复合材料的断口和抛光面通过扫描电镜观察。结果表明:通过等温化学气相沉积法在纤维表面沉积PyC/SiC界面相以后,复合材料的三点抗弯强度从46MPa提高到247MPa。沉积界面的复合材料断口有明显的纤维拔出现象,纤维与基体之间的结合强度适当,起到了增韧作用;而未沉积界面相复合材料的断口光滑、平整,几乎没有纤维拔出,纤维在热解过程中受到严重的化学损伤,性能下降严重,材料表现为典型的脆性断裂。
3D braided carbon fiber preforms were used to fabricate C/SiC composites using polymer infiltration and pyrolysis （PIP）. Before the PIP, the preforms were coated by isothermal chemical vapor infiltration with methane to produce pyrocarbon （PyC） and then with hexamethyldisilazane to form SiC and produce the PyC/SiC interphase. The correlation of the PyC/SiC interphase to the microstructure and the mechanical properties of the fabricated composites was investigated. The flexural properties of the composites were measured using the three-point-bend test, and the fracture surfaces observed by SEM. The bend strengths were 247 MPa and 46MPa, with and without the PyC/SiC interphase respectively. Long fiber pullout dominated the fracture surface for the composite with the PyC/SiC interphase, while for the one without the interphase, almost no fiber pullout was observed.
出处
《新型炭材料》
SCIE
EI
CAS
CSCD
北大核心
2007年第4期327-331,共5页
New Carbon Materials
基金
国家973计划项目~~
