Crashworthy and Performance-cost Characteristics of Aluminum-CFRP Hybrid Tubes under Quasi-static Axial Loading

Abstract

Metal/composite hybrid thin-walled structures combine the low cost of metallic materials and the high strength-toweight ratio of composites and thus have the potential to be utilized as cost-effective energy absorbers for vehicle applications. This study aimed to examine the crushing behaviors and performance-to-cost ratio of aluminum/carbon fiberreinforced plastic (CFRP) hybrid tubes under quasi-static axial loading. First, a single aluminum tube, a single CFRP tube and an aluminum/CFRP hybrid tube were tested to validate numerical models. The experimental results showed that the total energy absorption (EA) of the aluminum/CFRP hybrid tube was 32.46 % higher than the sum of that of the individual parts, and the special energy absorption (SEA) of the hybrid tube was improved by 105.26 % compared with that of the single aluminum tube. Then, the effects of the orientation angles ([±15°]n, [±45°]n, [±75°]n, [±90°]n, [90°/0°]n, n=2, 4, 6) and thicknesses of the CFRP tube wall (4-ply, 8-ply, 12-ply) on the crashworthiness of the hybrid tube were studied through validated numerical models. The numerical results showed that as the orientation angle increased, SEA, EA and the mean crushing force (Fmean) decreased first and then increased; in addition, the hybrid tubes with orientation angles of [±45°]n and [90°/0 °]n (n=2, 4, 6) consistently exhibited the worst and best crashworthiness, respectively. Furthermore, the SEA, EA, and Fmean of the hybrid tube increased with increasing thickness of the CFRP tube wall. Finally, the performance-to-cost ratio (SEA/cost) of the hybrid tube was analyzed, and the results show that aluminum/CFRP hybrid tubes with a smaller wall thickness of the CFRP tube exhibits superior potential in terms of both cost and performance for automotive applications.