Abstract: The hybrid joint has excellent mechanical properties, which combines bonding and riveting. However, due to the complex manufacturing process and numerous design parameters, it is difficult to guarantee its reliability. Therefore, it is necessary to identify and optimize the key parameters that affect the reliability of the structure, so as to control the quality fluctuation of the hybrid joint. This work proposes a set of identification and optimization methods for key parameters of the mechanical properties of CFRP-Aluminum hybrid joints based on 3D finite element simulation. By constructing a high-precision 3D finite element simulation model, a number of experimental quantitative uncertain sources from materials, geometry and assembly are introduced into the mechanical simulation, so as to realize the prediction of the randomness of the mechanical response. On this basis, the sensitivity analysis strategy based on the combination of polynomial chaos expansion and Sobol is used to quantify the relative contribution of each parameter to the response of the joint, and realized the identification of key parameters. The results show that the method can effectively and accurately determine the key parameters of the hybrid joint under the condition of considering the parameter uncertainty, and can be used to improve the design efficiency and quality of the hybrid joint.

Key words: carbon fiber reinforced plastic, aluminum alloy, hybrid joint, Sobol sensitivity analysis, reliability of mechanical properties