Design and development of self-diagnosis composites containing electrically conductive phase

Abstract

The electrically conductive fiber reinforced plastics (FRP) and ceramics matrix composites (CMC) have been designed and fabricated in order to introduce the self-diagnosis function in these materials. The electrical conductivity was achieved by adding conductive particles into the matrices of these composites. The FRP with percolation structure consisting of carbon particles had liner response of resistance to the tensile strain and high sensitivity in the wide strain range. The FRP embedded in mortar block successfully diagnosed micro-crack formation and propagation, showing that the self-diagnosis function of the FRP has the ability to monitor the health condition of concrete structures. The CMC materials containing TiN particles as a conductive phase indicated not only fine response of resistance to the applied strain but also resistance increase with increasing number of repetitions during cyclic bending test. These results suggest that these composites can be brought to many industrial applications concerning the self-diagnosis of deformation and damage in structural materials.