PSI - Issue 19

Francesca Curà et al. / Procedia Structural Integrity 19 (2019) 388–394 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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4. Conclusions

In the present paper the results of an experimental activity on multilayer nanocoated PU open cell foams are presented. Quasi-static and cyclic compression tests were performed. The particular aim was to characterize the effect of different number and kind of layers: PU and CNT nanoinks. The results of quasi-static cyclic preconditioning of specimens show that an increasing number of coating layers increases the maximum stress and the area of the hysteresis cycle. It can also be observed for all specimens a decrement in the maximum stress with cycles (stress softening) and this phenomenon is more evident increasing the number of layers. This difference in damaging behavior can be attributed to the coating layer contribution. This trend is linear for PU layers and non-linear for MW layers. For cyclic characterization the following parameters, obtained from the hysteresis loops, were chosen: Stiffness degradation, Secant modulus and Loss factor. 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