Mechanism of Interlaminar Strengthening and Toughening of Al/CFRP/Al Composite Laminates

To solve the problem of easy delamination of the interface of Al/CFRP/Al laminate (CFRP, carbon fiber composite; Al, aluminum), a method of constructing high strength and toughness at the interface is proposed. The effects of adding resin and carbon nanotubes at the interface on the shear, flexural strength and impact resistance of Al/CFRP/Al laminates are studied. Experimental results show that gullies and micropores can be formed on the surface of aluminum after pretreatment, and the contact area between aluminum and matrix can be increased. After resin is added to the Al/CFRP interface, the shear strength between layers and the bending strength and impact resistance of laminates are improved. Mixing carbon nanotubes into the added resin will further improve the mechanical properties of laminates. On the basis of strengthening and toughening the Al/CFRP interface, the carbon nanotubes added between the CFRP layers can strengthen and toughen the resin at the interface, which enhances the bending strength and impact resistance of the laminates. When the resin between the layers breaks, the carbon nanotubes will be pulled off and pulled out to resist the damage of the resin, and the carbon nanotubes at the end of the crack can hinder the propagation of the cracks.