The CFRP-Al hybrid thin-walled structure combines the dual advantages of carbon fiber reinforced plastics (CFRP) and metal, which is one of the crucial methods for both lightweight and high strength. This study aimed to explore the theoretical prediction of the mean crushing force of the hybrid tubes with different winding angles subjected to axial compression. In order to construct the theoretical model of the hybrid structural energy absorption response, the failure modes, and deformative behavior of the hybrid tubes are analyzed and summarized based on the axial compression experiments. Considering the effects of winding angles on the energy dissipation and deformation characteristic of hybrid circular tubes, the expressions of membrane force and binding energy per unit length are obtained. Then, the analytical model is established to predict the mean crushing force of the CFRP-Al hybrid circular tube. Furthermore, the results of the prediction model are compared according to different failure criteria of composite materials. The findings show that the predicted values of the maximum stress failure are more consistent with the experimental values, in which the discrepancy between analytically predicted and experimentally tested mean crushing forces of these hybrid tubes is no more than 10%. The results can provide a basis for the design of the composite-metal hybrid thin-walled tube.

To find a thin‐walled impact‐resistant structure with excellent crushing performance, a multi‐cell hybrid thin‐walled tube (MCHT) formed by winding carbon fibers around a multi‐cell Al tube was proposed. The structure is designed based on different structural parameters of the thin‐walled tubes exhibiting different crushing characteristics and damage modes. First, a finite element model applicable to MCHT is established, and the accuracy of the model is verified by quasi‐static axial pressure experiments. Second, the verified finite element model was used to study the variation law of the overall structural crushing performance by changing the structural parameters of MCHT, and the Al tube wall thickness was found to have the greatest effect on MCHT crushing performance, followed by the number of ribs and finally the inner circle diameter. Then, a theoretical prediction model of the mean crushing force of MCHT was established based on the principle of energy conservation, and the accuracy of the theoretical model was initially verified through experiments. Finally, to overcome the problem that the prediction error of the theoretical model is larger when the number of ribs is larger or the inner circle diameter is smaller, a correction function is constructed based on Pearson correlation coefficient analysis to further improve the generalization ability of the above‐mentioned theoretical model, and the maximum relative error is reduced from 37% to 14.61%.

This paper aimed to investigate the bending collapse and optimization of carbon fiber reinforced plastics/aluminum (CFRP/Al) hybrid tubes with different parameters through the three-point bending test. Based on the experimental tests, the transverse energy absorption of upon hybrid tubes was found to be higher than net aluminum tube, and the overall strain and internal failure mode of the CFRP/Al hybrid tube were observed by digital image correlation technology and X-ray computed tomography scan. The failure of outer CFRP and interaction between aluminum and CFRP was the main factor to improve loading capacity and energy absorption, and various parameters configuration of CFRP and aluminum are of their own benefits. Afterward, the validated numerical simulation model was carried out by correlating with the test results. Based upon the numerical simulation model, the parametric study and design optimization on the CFRP/Al hybrid tube (concerning the thickness of aluminum, ply angle, and layer number of CFRP) were further conducted systemically. It was found that the optimization results were θ = 15°, t = 1.65 mm, n = 3, which decreased the peak force ( F max) by 10.82%, mass is reduced by 13.0%, and specific energy absorption ( SEA) shows almost no change.