Research on the deformation law of ultra-thin fiber metal laminates under the synergistic effect of nano-reinforcement and scale effect

[Display omitted] •The mixed solution of acetone-epoxy resin containing multi-walled carbon nanotubes was prepared by ultrasonic dispersion.•The effects of MWCNT content, test temperature and strain rate on the properties of FMLs were systematically investigated.•The enhancement mechanisms of multi-walled carbon nanotubes mainly involve fracture, pull-out and crack bridging.•As the geometric ratio increases, necking occurs and the outermost metal produces an edge curl effect.•With the increase of grain size, the fracture mode changes from microporous aggregated fracture to cleavage fracture. At present, titanium alloy/carbon fiber reinforced polymer (TA1/CFRP) laminates, representing the latest fourth generation of fiber metal laminates (FMLs), are predominantly applied in the field of aerospace. The miniaturization of traditional FMLs in thickness or plane size to the micron level for the study of structural properties of ultra-thin laminates will further expand the application of FMLs in the field of micro-devices. Given that carbon nanotubes have a strengthening mechanism in polymers. However, most existing studies have focused on the effect of carbon nanotubes on the properties of macro-scale FMLs, while the enhancement mechanism of the interfacial and mechanical properties of ultra-thin micro-scale FMLs has not been studied, leaving the mechanism still unclear. Based on this, this paper explores the interfacial deformation mode, damage fracture and performance enhancement mechanism of the ultra-thin TA1/CFRP laminates by comparing the parameters of tensile strength and elongation under quasi-static conditions and different process parameters of multi-walled carbon nanotubes content, test temperature, geometry size and grain size. Meanwhile, the correlation law between high-speed tension and quasi-static tension is determined, a 29.3 % increase in tensile strength as the strain rate rises from 0.001 s−1 to 100 s−1, yielding the basic deformation law of ultra-thin FMLs.