Effect of composite design parameters on the inverse magnetostrictive characteristics of hybrid carbon fiber reinforced plastic embedded with Fe-Co fibers

Carbon fiber reinforced plastic (CFRP) has been generally chosen in the areas where weight reduction is important, for instance, sports goods and aerospace. For safe operation of the system using CFRP, we have to assess the damage state and predict the remaining service life accurately, which is one of the critical issues to keep the reliability in CFRP applications. Recently, multi-functional CFRP, especially embedded with piezoelectric or magnetostrictive materials, has been explored to realize lightweight battery-free sensors for structural health monitoring (SHM). In present study, the hybrid CFRP embedded with magnetostrictive Fe-Co fibers was developed, and the effect of composite design parameters (e.g. diameter of the fibers, location of the layers, bias magnetic field) on the inverse magnetostrictive response characteristic was also investigated. Mechanical cyclic bending tests showed that the fluctuation of magnetic flux density was measured resulting from the flexural deformation of our hybrid CFRP. Moreover, the measured magnetic flux density changed drastically when the CFRP was damaged, which implies that our hybrid CFRP has damage self-sensing ability. It seems that we should experimentally and numerically design and investigate the hybrid CFRP with magnetostrictive Fe-Co fibers in order to improve the capability as sensor composite materials. Accordingly, this study must make contribution to feasibility of lightweight, buttery-free, high performance stress sensors for SHM.