Research Initiation: Influence of Carbon Fibers Surface Modifications on Mechanical Properties of C-C Composites

这项为期2年的碳-碳复合材料界面和力学性能研究的目标是：(1)找到有效的表面处理和去处理，以降低化学键合，增加机械键合和界面摩擦系数；(2)确定表面官能团与纤维向基体载荷传递机理、界面结合强度和断裂韧性之间的相关性。纤维表面处理将包括氧、氩等离子体蚀刻和硝酸处理。处理过和未处理过的纤维的表面特性将用化学分析的电子能谱和傅里叶变换红外光谱来确定。C-C复合材料将使用经过处理和未经处理的织物生产。所有的复合材料将使用电子显微镜、破坏性和非破坏性力学测试进行分析。由此产生的机械性能将与织物的表面性能相关。本研究将利用弱化学键、机械键和高界面摩擦系数来回答与基体协同作用机制有关的基本问题。此外，本研究结果将有助于优化C-C复合材料的机械性能，增加其更广泛的技术应用机会。

The objectives of this 2 year study of the interfacial and mechanical properties of Carbon-Carbon Composites are: (1) to find effective surface treatments and de-treatments which would lower the chemical bonding and increase mechanical bonding and interfacial coefficient of friction; and (2) to determine the correlation between surface functional groups and the mechanism of load transfer from fiber to matrix, interfacial bond strength and fracture toughness. The fiber surface treatments will include oxygen, argon plasma etching and nitric acid treatment. The surface characteristic of treated and untreated fibers will be determined using Electron Spectroscopy for Chemical Analysis and Fourier Transform Infrared Spectroscopy. The C-C composites will be produced using both treated and untreated fabrics. All the composites will be analyzed using electron microscopy, destructive and non-destructive mechanical testing. The resulting mechanical properties will be correlated with the surface properties of the fabrics. This study will answer the fundamental question related to synergetic mechanism of the matrix by employing weak chemical bond, mechanical bond and high coefficient of interfacial friction. In addition, the results of this research will assist in the optimization of mechanical properties of C-C composites, increasing their chances for wider technological applications.