CARBON NANOTUBES BASED SENSORS FOR DAMAGE DETECTION

In this paper Multi-walled Carbon Nanotubes (MWNTs) - based nanocomposite films were investigated as dynamic strain sensors for damage detection. After a thorough study to optimize the electromechanical properties of the material as a function of the MWNTs content, the proof-of-concept was carried out by installing the film onto the surface of a fiberglass cantilever. The cantilever was made to oscillate through an impulsive force applied at its free end. The free oscillations of the structure are monitored and the frequencies are identified before and after reducing locally the cross section of the cantilever (to simulate damage propagation). The experimental data show the capability of the manufactured nanocomposite film to clearly identify structural frequencies in dynamic regimes. The obtained experimental data also show that this material has the potential to monitor incipient cracks (nano/micro-scaled cracks) due its sensitivity to nanoscale morphology changes.