The characterization of the flexural and shear performances of laminated aluminum/ jute-basalt fibers epoxy composites containing carbon nanotubes: As multi-scale hybrid structures

In this study, firstly the fiber metal laminates (FMLs) were fabricated by using aluminum sheets as skin layers and jute/basalt fibers with the different stacking sequences (sandwiched and intercalated structures) as core of structures. Then, the carbon nanotubes (CNTs) were dispersed into the epoxy resin for fabricating the FMLs with the proper flexural and shear properties. Also, the macro and micro-structural observations were performed to characterize failure mechanisms into these structures. The obtained results showed that the FML with the stacking sequence of jute sandwiched by the basalt fibers had the highest mechanical properties. Incorporating 0.3 wt% CNTs caused to achieve the highest flexural strength, flexural modulus and shear strength in this FML, which were 635 MPa, 54 GPa and 27.1 MPa, respectively. The tearing and plastic deformation of aluminum layers, fracturing and pulling out the basalt fibers, fracturing and crossing the cracks between the jute layers, delamination between aluminum and composite core were the characterized failure mechanisms. Also, creating the CNTs/epoxy nanocomposite adhesive agent on the interface of skin/core in the FML structures, fibrillating the jute fibers, pulling out CNTs, and adhering distinct fibers/epoxy were the characterized as influence factors on the mechanical properties.