Theoretical analysis and crashworthiness optimization of multi-cell Al-CFRP hybrid tube

Abstract

In this paper, a hybrid thin-walled tube with multiple cells and multiple materials is proposed to achieve lightweight, high energy absorption efficiency, and low cost of structures. Energy absorption characteristics and crushing deformation of the hybrid structures are investigated by experimental testing and numerical analysis. Meanwhile, theoretical prediction models of the mean crushing force for hybrid structures are developed and its accuracy was verified. It is found from the sensitivity analysis that the parameters of the multi-cell structure have significant effects on energy absorption. Furthermore, the multi-objective optimization including surrogate models is performed to obtain optimal crashworthiness of the multi-cell hybrid tube. The same optimal results were obtained using the full factor response mapping optimization algorithm and the non-dominated sorting genetic algorithm with elite strategy algorithm for multi-objective optimization solution. Compared with the original multi-cell hybrid tube and multi-cell pure aluminum (Al) tube, the optimized structure showed an increase of 0.25% and 25.31% in specific energy absorption, an increase of 16% and 77.34% in average crushing force, and an increase of 3.89% and 23.08% in energy absorption efficiency, respectively.