Comparative analysis for strain response and life monitoring of composite using carbon-based nanosensors

Sensing technology based on carbon nanomaterials has become a very promising technology in the field of composite health monitoring, which requires high-sensitivity piezoresistive strain sensors to serve. In this study, two different carbon nano-sensors were used. Based on the traditional carbon nano-paper sensor, a flexible printed circuit and a polysulfone membrane were added to ensure the stability and sensitivity of the sensor. The conductive mechanism of adjacent carbon nanotubes (CNT) was analyzed. The electrical network model inside the carbon nanosensor was established, and its working mechanism during loading and unloading was described. The research mainly adopts three-point bending experiment. The deformation and failure of composite laminates containing two kinds of sensors under load experience low strain and high strain cyclic loading. Both sensors have the same response and stability as the load growth trend. Experiments show that the CNT-Paper sensor is suitable for long-term health monitoring of composite materials. The carbon nanotube-ultrafiltration membrane (CNT-UM) sensor is more sensitive to the cyclic monitoring of small strain.