Influence of carbon nanotube on interfacial and mechanical behavior of carbon fiber reinforced epoxy laminated composites

Reinforcing carbon fiber epoxy composite (CF-EP) with carbon-based nano-fillers offers outstanding mechanical and interfacial properties by strengthening the weak fiber-matrix interface (delamination) and enhancing the fiber pull-out strength of neat CF-EP. In this study, a multiscale CF-EP laminated composite with CNT modified epoxy matrix has been fabricated by a vacuum-assisted resin infusion method. Dispersion of 0.3 wt% CNTs into the epoxy are carried out using a probe sonicator. The outcomes indicate that the incorporation of 0.3 wt% CNTs in CF-EP can improve the ultimate tensile strength (UTS) and interlaminar shears strength (ILSS) by 17% and 28%, respectively. Modulus gradient evaluation across the interface revealed the improvement in the stability of the interface with nanofiller addition. Further, energy absorption during delamination is also improved by 26.31% more due to better interfacial bonding offered by nanofillers.