More than 80% of failure in polymeric materials occurs due to fatigue. The local phenomena associated with periodic loading in polymers is of complex nature and can involve a superposition of effects such as creep, molecular orientation, crazing etc. In the case of polymer composite/nanocomposite materials, in addition to phenomena associated to the polymer matrix, it is of utmost importance to detect and understand the complex interactions between the material constituents, namely matrix-reinforcement interaction, debonding, fracture propagation, toughening mechanisms etc. In this framework, we develop a state-of-the-art high sensitivity approach coupled with advanced data analysis methods to investigate the damage mechanisms in polymer composite/nanocomposite materials.
To summarize, the experimental technique involves the acquisition of raw output signal data, use of oversampling technique and subsequent advanced data analysis. Oversampling is applied in order to improve the accuracy/signal-to-noise ratio of the signal and provide access to nonlinearities beyond the linear viscoelasticity limit of the material, i.e. in the weakly nonlinear regime. The final goal of the pilot project is to create the infrastructure necessary for outstanding research opportunities in the field of fatigue analysis of polymer composite/nanocomposite