Structural damping properties of composites interleaved with functionalized nonwoven fabrics

A new structural damping composite was prepared by interleaving polyamide nonwoven fabrics modified by PVDF between the carbon fiber reinforced epoxy composites via co-cured method. The static mechanical properties of co-cured composites were estimated by measurement of flexural strength, flexural modulus and interlaminar shear strength. The temperature spectra of storage modulus and loss factor were measured, and single cantilever beam vibration experiment was conducted to analyze the vibration damping characteristics. The micro structure and damping mechanism of co-cured composites were analyzed by optical microscopy and scanning electron microscopy. Results indicate that the damping properties can be significantly improved by inserting modified PNF with comparatively lower decline of mechanical properties. The loss factor of composites with seven layers of modified PNF was 0.008 3, 72.9% more than the control sample, and flexural modulus was only 16.3% lower than the control sample.