Characterization of the interface and interphase region in the multi-walled carbon nanotube modified epoxy resin/carbon fiber hybrid nanocomposite

In this study, the interphase of multi-walled carbon nanotubes (MWCNTs) modified epoxy resin/carbon fiber composite is evaluated in detail. The composites are manufactured using a filament winding machine. The nanomechanical and tribological properties of the interphase region and the exact position of the interface in the composites are studied by nanoindentation and nanoscratching test methods. Results are shown that the hard to soft interphase region thickness (tH/tS) ratio increased 84% and 200% by the addition of 0.5 and 1.0 wt.% MWCNTs into epoxy/carbon fiber composites, respectively. Also, increases in elastic modulus and hardness up to 41% are observed in the matrix of nanocomposite containing 1.0 wt.% MWCNTs than the MWCNTs free matrix. In addition, the resistance to plastic deformation of the matrix was improved by 37% by incorporating 1.0 wt.% MWCNTs into the matrix. As a result, the use of MWCNTs improves the tH/tS ratio and mechanical properties of the matrix due to the enhancement of the load transfer between matrix and CF in the interphase region of the hybrid nanocomposite. By exploiting the executed analyses, MWCNTs can be modified properties of epoxy/CF composites for advanced industries.