Real-time and visible monitoring of stress distribution using organic mechanoresponsive luminogen

A real-time and visible stress monitoring method based on a pure organic mechanoresponsive luminogen (MRL) was proposed in this work. 1,1,2,2-tetrakis(4-nitrophenyl)ethene (TPE-4N) could produce ultrasensitive and visible mechanoresponsive fluorescence. Metal specimens were coated with a uniform TPE-4N film, wherein mechanical deformation was transformed into visible fluorescence. Tensile tests were conducted to determine the calibration relationship between the stress value and fluorescence intensity. The accuracy of stress measured using the organic MRL method was investigated on single-edge notched tension specimens. Results show that the stress distribution obtained using the proposed method agrees well with that calculated using ANSYS simulation. The organic MRL method may open up new opportunities for large-scale, full-field, on-site monitoring of stress distribution in complicated structural components.