Attenuation of Ao Lamb mode in hybrid structural composites with nanofillers

This paper focuses on quantification of attenuation coefficient of fundamental anti-symmetric (Ao) Lamb wave when it propagates through hybrid structural composites with nanomaterials. Investigations were carried out on nanosilica and carbon nanofiber hybridized-glass and carbon fiber reinforced epoxy composites in comparison to their respective control composite laminates with no nanofillers. Composite specimens were fabricated through Resin Film Infusion (RFI), ensuring near zero void fractions. Effective and actual attenuation characteristics of Ao mode were evaluated at three different frequencies – 100 kHz, 200 kHz and 500 kHz in hybrid glass and carbon based composites. It is observed that effect of the nanomaterials (nanofillers) on attenuation of Ao mode is more significant at high frequencies. Furthermore, attenuation behavior of Ao mode depends on the type of nanomaterial. It is also observed that Ao mode undergoes more attenuation in glass fiber reinforced composites compared to their carbon fiber based counterparts, irrespective of the nanomaterials.