Fabrication and electromechanical performance of carbon nanotube based conductive membrane and its application in real-time multimode strain detection in composites

In this study, a flexible conductive membrane (CM) consisting of a network of carbon nanotubes is produced and the electromechanical behavior of this CM was studied experimentally and the gauge factor (GF) of CM was in the 8–8.25 range. Then, a multi-mode strain detection is carried out in composites using this CM sensor. The CM is embedded gradually at directions i.e. 0°, +45°, 90°, −45° between the plies for real-time/in-situ strain monitoring. The composite specimens are then cut in star profile and then tested under tensile and bending cyclic loading. There is a good reproducibility in the results and the mechanical response of composite correlated perfectly with the electrical resistance of the CM sensor however, a sensor in each position showed distinct behavior. The results established that the CM sensor exhibited good potential as a flexible strain sensor for in-situ monitoring of composites and can provide detection over a large section and unapproachable locations.