Rolling preparation process and interface toughening mechanism of Al/CFRTP/Al composite laminates

In this study, a highly efficient method for preparing Al/CFRTP/Al composite laminates by roller preparation was proposed. Three different surface treatments, namely, anodic oxidation, laser texture and surface modification, were used to improve the strength of the metal-fiber interface. Results show that composite laminates can be prepared efficiently by using reasonable roll pressing technology. The composite laminates with a thickness of 3 mm has good shear strength when the reduction amount is 0.02 mm. Laser texturing increases the contact area at the laminate interface. The surface roughness of Al alloy sheet is improved after laser texture. Moreover, the matrix in the fiber layer of the laminate can be embedded in the gullies formed by the laser texture to form a mechanical interlocking structure. The shear strength of the laminates was further increased when the laser scanning spacing was 2 mm. The highest shear strength of the laminate is 52.4 MPa after using a coupling agent to modify the surface of the Al alloy sheet. X-ray photoelectron spectroscopy analysis showed that a new chemical bond was generated at the interface between CFRTP and the Al alloy sheet modified with silane coupling agent, thereby forming a molecular bridge among different materials. Mechanical interlocking structure and the generation of new chemical bonds cause the interface to need to absorb more energy during the failure process, which is conducive to the improvement of the interface strength.