Strength improvement and mechanism analysis of thermoplastic fiber metal laminates using multi‐field‐assisted forming method

Abstract Fiber metal laminates (FMLs) are an innovative hybrid material formed by laminating metal with fiber‐reinforced plastics. Due to their excellent functional characteristics, FMLs are extensively employed in the automotive and aerospace industries. Nevertheless, the strength of FMLs is significantly influenced by various interfaces, making it crucial to explore strategies for further enhancement and conduct an in‐depth mechanism analysis. Consequently, this research proposes a novel multi‐field‐assisted forming method for thermoplastic fiber metal laminates (TFMLs) composed of 5052 aluminum alloy, carbon fiber PA6 prepreg, and hot‐melt adhesive film. A multi‐field‐assisted forming platform was established comprising a hot‐press unit, an ultrasonic device, and a pulsed current device. Orthogonal experiments were conducted to optimize the forming process parameters for improving the multi‐fields coupling formability. The results demonstrate that the multi‐field‐assisted forming method enhanced tensile and bending strengths by 19.76% and 17.55%. To explore the effect of the ultrasonic field and electromagnetic field acting separately, the mechanisms by which multi‐fields enhance the mechanical properties of TFMLs are elucidated independently. Additionally, the multi‐field‐assisted forming analysis indicates that both ultrasonic and electromagnetic fields improved the forming quality of curved components. The present study can provide an initial research foundation for the multi‐field‐assisted forming process of FMLs. Highlights A novel multi‐field‐assisted forming method for TFMs was proposed. The forming process parameters were optimized. The multi‐field‐assisted forming method improved the forming quality. The enhancement mechanisms of forming quality were elucidated.