Structural health monitoring for polymer composites with surface printed MXene/ink sensitive sensors

摘要

In this study, a novel sensor with high sensitivity and linear was prepared based on two-dimensional (2D) material (MXene) and ink, which can be used for deformation and damage monitoring of structural composites. The MXene was efficiently prepared by etching Ti_3AlC_2 powder with LiF-HCl solution and subsequent vacuum drying. The viscosity and adhesion of MXene/ink composites were controlled by changing the ratio of solvent (dimethyl sulfoxide) to ink. The MXene/ink was printed on the surface of the composite material to avoid forming defects in the composite material. The percolation threshold of the MXene/ink nanocomposite was relatively low, 3.6wt%. In this paper, MXene/ink composites with different contents were selected as the sensor, and the characteristics of the sensor were verified through monotone stretch and cyclic load-and-unload tests. When the MXene content just exceeds the percolation threshold (4wt%), the gauge factor (GF) of the sensor is higher, the results of monotonic tensile experiment show that there are two different sensitive stages of linear change (0～0.477%) and (0.477 ～ 1.37%), and the range GF is 116.6 and 554.3, respectively. In addition, the linear relationship and sensitivity of the sensor remained stable after loading and unloading tensile tests. MXene/ink sensor has a broad application prospect in damage monitoring of aerospace structural composites.