Study of composite joint strength with carbon nanotube reinforcement

Abstract

Strengthening of composite joints is a topic of recent research. The benefits of using locally applied carbon nanotubes to reinforce a carbon fiber composite joint were studied. The effect of carbon nanotubes on enhancing the fracture toughness and joint interface strength was investigated by performing Mode I, Mode II, and Mixed Mode I/Mode II fracture with and without carbon nanotubes applied locally at the joint interface. Furthermore, the effects of seawater absorption on Mode II fracture were investigated. Finally, an optimization of carbon nanotube concentration was performed. During the study, the image correlation technique was used to examine the fracture mechanisms altered by the introduction of carbon nanotubes. The experimental study showed that carbon nanotubes can increase the fracture toughness of the composite interface significantly, especially for Mode II, including a physical change in the fracture mechanism.