The multifunctional application of carbon fiber reinforced polymer composites (CFRP) can be affected by the anisotropic electrical conductivity of the carbon fiber because it differs in the longitudinal and the transverse direction of the fiber. In our article, we measured the transverse resistivity of the reinforcing carbon fiber bundle in different conditions: when the fibers were dry, when they were impregnated with non-crosslinked resin, and in a crosslinked matrix. We have shown that in the case of dry and impregnated fibers, a compressive force acting on the fiber bundle has a significant effect on the transverse resistance, while when crosslinked, this effect is negligible. We developed a finite element model (FEM) to investigate the area around the electrodes and the current distribution in the fiber bundles. We have shown that due to the pressure dependence of the transverse resistance and the significant difference in length and transverse conductivity, the current density distribution in the cross-section around the current electrode will not be homogeneous, leading to inaccuracies in sensory applications. We have shown by finite element simulation that the current electrode and voltage measurement electrode can be optimized, which was verified experimentally.

中文翻译：

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多功能碳纤维传感器：各向异性电导率的影响

碳纤维增强聚合物复合材料（CFRP）的多功能应用可能会受到碳纤维各向异性导电性的影响，因为它在纤维的纵向和横向上都不同。在我们的文章中，我们测量了增强碳纤维束在不同条件下的横向电阻率：当纤维干燥，何时用非交联树脂浸渍以及在交联基质中。我们已经表明，在干燥和浸渍的纤维的情况下，作用在纤维束上的压缩力对横向阻力有显着影响，而在交联时，这种影响可以忽略不计。我们开发了一个有限元模型（FEM），以研究电极周围的区域以及纤维束中的电流分布。我们已经表明，由于横向电阻的压力依赖性以及长度和横向电导率的显着差异，电流电极周围横截面中的电流密度分布将不均匀，从而导致感官应用中的误差。通过有限元仿真，我们已经证明可以优化电流电极和电压测量电极，并通过实验进行了验证。