Influence of fracture toughness on the impact properties of carbon nanotubes/aramid fibre reinforced composite

This research was carried out to investigate the relation of the fracture toughness of epoxy/CNT/twaron on the impact properties by dividing into two phases and use design of experiment (DoE) approach. In Phase 1, the effect of parameters such as epoxy viscosity, CNT content, stirring time, stirring speed and sonicating time on fracture toughness of epoxy/CNT composite were studied. The fracture toughness of epoxy/CNT composite was determined by using Single Edge Notch Bending (SENB) and indentation method. The Phase 2 was the continuity of the Phase 1 of the research,
which the result will be used to fabricate the sample of epoxy/CNT/twaron composite. The effect of fracture toughness on the energy absorption will be studied by manipulating the CNT loading, number of layers, projectile velocity. The readings of the fracture toughness by using SENB and the indentation method were recorded from 78.764 to 287.092 MPa.mm0.5 and 30.06 to 99.23 MPa.mm0.5. From the analysis of
variance (ANOVA), it was found that the epoxy viscosity, CNT loading, stirring speed, and sonicating time was the significant parameters, which were affecting on the fracture
toughness by using SENB method. Meanwhile, epoxy viscosity, CNT loading and stirring speed were significant parameters for the indentation method. From the analysis, two statistical equations were generated. In Phase 2, the energy absorption was recorded in the range from 47.44 to 303.45 J. From the ANOVA analysis, CNT loading and numbers of layers were the significant parameters which affected the energy
absorption of epoxy/CNT/twaron composite. A statistical model was derived.