Multifunctional carbon/epoxy composites with power transmission capabilities

This study evaluates the power transmission of multifunctional composites with embedded conductors. The electrical conductors were constructed by braiding copper strands with Para-aramid fibers into a tape configuration, then placing these tapes within carbon/epoxy prepregs to create a multifunctional structure. Experiments were performed on these multifunctional composites under tensile loading conditions. During experimentation, the conductive tapes were incorporated within an electrical bridge to record their resistance change as a function of mechanical strain. The Digital Image Correlation (DIC) technique was used to obtain in-plane displacements and strains as a function of time. In addition, low-speed flight condition experiments with an airfoil shape composite system were carried out in a wind tunnel to study the temperature performance of these structures while under high currents. Computational models were then created to expand the experimental efforts and evaluate the system's multiscale performance. Experimental results show that the mechanical load on the conductive tape is mainly carried by the Para-aramid yarns, leading to a relatively consistent electrical performance and airflow over the wind foil providing efficient power transmission. Lastly, the computational models showed consistency in the electrical/mechanical results and established a framework for analyzing multifunctional structures (MFS).