Crucial parameters and influence rules of axial crushing energy absorption of CFRP-Al hybrid columns

To investigate the failure behavior and energy absorption characteristics of carbon fiber reinforced polymer (CFRP)-aluminum alloy (Al) open-section hybrid columns under axial load, the combination of quasi-static crushing test and finite element method were employed to analyze the effects of different crucial parameters on axial crushing failure behavior and energy absorption characteristics of CFRP-Al hybrid columns. The results show that the Al model with single-layer shell adopted the elastic-plastic constitutive and GISSMO damage model, as well as the CFRP model with laminated shell adopted the Chang-Chang intralaminar failure criterion and the B-K interlaminar damage model can accurately simulate the axial crushing failure behavior and energy absorption characteristics of CFRP-Al hybrid columns. Through the analysis of crucial parameters such as relative thickness ratio, fillet ratio, opening angle, gradient and induced hole, the specific energy absorption of CFRP-Al hybrid columns reaches a higher level with the relative thickness ratio η=67%, fillet ratio γ=50%, opening angle θ=120°, gradient T=8, and induced hole K=1. By coupling the optimal values of the crucial parameters, the axial crushing energy absorption of the CFRP-Al hybrid column increases by 46.81%, and the specific energy absorption increases by 49.06%.