An investigation of the performances of embedded Buckypapers within a 0/90 WC glass fibre reinforced composite specimen with a delamination, under tensile loading

Buckypapers (BP) are made from CNT that arrange to produces a thin layer which are bonded to each other by van der Waals forces. One of the sensitive characteristic of a buckypaper is change of its resistance due to a nano scale change to its geometry. Due to this reason BP has been widely researched for strain measurement of various structures and became a potential candidate for sensing of structural performance under operational loading. Due to compatibility with fibre reinforced composites; BP is becoming an attractive candidate for structural health monitoring (SHM) of composite structures. This paper detailed an investigation conducted on embedded BP strips closer to a purposely created delamination within a glass fibre composite sample under tension loading. In this study, a FBG sensor was also embedded at a location closer to BPs for comparison purpose. The change of electrical resistance of BP under tensile loading was investigated. Interestingly the change of electrical resistance of BPs was following the same trend as FBG sensor strain readings. Further, when the delamination damage approach the locations of BPs, the measured resistance of BP has increased significantly showing strain concentrations around the crack tip.