Self-sensing impact damage in and non-destructive evaluation of carbon fiber-reinforced polymers using electrical resistance and the corresponding electrical route models

Abstract

Carbon fiber-reinforced plastics (CFRPs) made of uni-directional carbon fibers (UDCFs) are used in various applications such as construction, aerospace, and automobiles. Therefore, their structural health monitoring (SHM) and non-destructive evaluation (NDE) are important to ensure safety during operation. While there is literature on self-sensing of CFRPs to realize various properties, there is no information on their impact self-sensing properties. Therefore, in this study, CFRPs in several orientations were investigated in terms of their mechanical fracture and electromechanical behavior. Changes in their electrical resistance due to impact damage can be utilized for SHM using the corresponding electrically equivalent circuit models. The circuit models constructed consisted of electrical resistors that described the UDCFs. In addition to converting CFRPs into 2D circuits, 3D electrical routes between electrodes were proposed for NDE. Calculating the detour length of the electrical routes using the proposed models helps in assessing the severity of the impact damage. Therefore, the models for CFRPs developed in this study not only provide support for SHM but also for NDE using electrical resistance. © 2021