Experimental Study on Energy Absorption Mechanism of Aluminum / GFRP Composite Hybrid Tubes Subjected to Lateral Impact Loads

ABSTRACT Aluminum‐glass fiber reinforced polymer (GFRP) hybrid tubes integrate the stable and ductile plastic deformation mechanism of aluminum with the superior strength‐to‐weight ratio of fiber/resin composites, forming composite structures with enhanced energy absorption capacity. In this paper, three types of aluminum‐GFRP hybrid tubes with distinct fiber layup configurations ([0°/90°] ₂ , [45°/−45°] ₂ , and [90°/0°] ₂ ) were fabricated on the surface of 1‐mm‐thick pure aluminum tubes via the vacuum‐assisted resin injection molding process. The post‐impact crushing behavior and post‐impact energy absorption characteristics were investigated through low‐velocity impact tests at a variety of energy levels of 5, 10, and 15 J. The results indicate that, in comparison to pure aluminum tubes, the three hybrid tubes exhibit significant improvements in compressive strength and crushing force efficiency (CFE) following lateral impact. Under a 15‐J impact, the CFE of the specimen with [0°/90°] ₂ was 0.73, representing a 55% increase over that of the pure aluminum tube. Higher impact energy levels increase the likelihood of localized instability failure. The outermost 90°fiber layer provides the most effective structural confinement, showing outstanding energy absorption performance and contributing to the lightweight design of thin‐walled structures.