纳米压痕技术测试纤维束内沥青炭和粗糙层热解炭的力学性能

Mechanical properties of pitch carbon and rough laminar pyrocarbon in beams through nanoindentation technique

为了研究纤维束内沥青炭和粗糙层热解炭的力学性能,以2.5D针刺炭毡为增强体,分别通过中温煤沥青浸渍炭化和化学气相沉积制备得到C/C复合材料。使用G200型纳米压痕仪对C/C复合材料纤维束内基体进行纳米压痕测试,采用连续刚度测试方法,利用Oliver和Pharr模型获得试样弹性模量随测试深度的变化,利用弹性模量和硬度两参数Weibull分布函数对纳米压痕测试结果进行统计分析。结果表明,沥青炭和粗糙层热解炭的弹性模量平均值分别为(14.92±2.02) GPa和(12.87±1.35)GPa;硬度的平均值分别为(0.64±0.14) GPa和(0.67±0.17) GPa。沥青炭和粗糙层热解炭的弹性模量的Weibull分布模数分别为8.60和9.18,弹性模量的特征值分别为15.63 GPa和13.40 GPa。

In order to study the mechanical properties of pitch carbon and rough laminar pyrocarbon, the C/C composites were prepared through impregnation carbonization of medium coal tar pitch and chemical vapor deposition with 2.5D needled carbon felt as reinforcement. The nanoindentation test of C/C composites was carried out by G200 nanoindenter, the change of elastic modulus with depth was obtained using continuous stiffness measurement and Oliver and Pharr model. The results showed that the average values of the elastic modulus of the pitch carbon and rough laminar pyrocarbon are(14.92±2.02) GPa and(12.87±1.35) GPa, respectively.The average values of the hardness of the pitch carbon and rough laminar pyrocarbon are(0.64±0.14) GPa and(0.67±0.17) GPa, respectively. The Weibull distribution modulus of the elastic modulus of pitch carbon and rough laminar pyrocarbon are 8.60 and 9.18,respectively. The eigenvalues of the elastic modulus are 15.63 GPa and 13.40 GPa, respectively.