Enhancing interlaminar fracture toughness of CFRP laminates with hybrid carbon nanotube/graphene oxide fillers

Abstract

The study focuses on the improvement of the interlaminar fracture toughness of Carbon Fiber Reinforced Polymer (CFRP) with graphene oxide (GO) and multi-walled carbon nanotubes (MWCNTs) in different ratios. A simple and convenient method was used to spray a density of 1.1 g/m2 nanofiller onto the surface of CFRP prepreg. Meanwhile, the ability of resistant temperature changes from −58 °C to room temperature was employed and evaluated. The influence of nanofillers on the interlaminar fracture toughness of CFRP laminates was examined via the double cantilever beam (DCB) test and end notched flexure (ENF) test. Results show that the addition of MWCNTs and GO greatly enhanced the interlaminar fracture toughness with different strengthening mechanisms. In particular, the laminates with the nanofillers ratios of MWCNTs/GO = 8:3 and MWCNTs/GO = 10:1 presented the optimal performance for the mode I and mode II fracture toughness, with remarkable improvements of 151.52 % and 215.15 % are achieved compared with the original laminates without nanofillers respectively. Moreover, the composites reinforced by hybrid nanofillers display a similar toughening trend after the temperature cycle proving the reliability and synergy of hybrid nanofillers. Fracture surface morphology was analyzed by scanning electron microscopy (SEM).