Crashworthiness of AA6060-T4 Crash Boxes at Different Drop Heights

Abstract

Purpose: The study investigates the crashworthiness of corrugated AA6060-T4 aluminium crash boxes under axial impact loading, focusing on the effect of drop height on their corresponding energy absorption and deformation behaviour. Design/methodology/approach: Drop-weight impact experiments were conducted at heights of 1, 2, and 3 m to obtain force–displacement responses. In parallel, finite element simulations using ANSYS were performed to validate the experimental results. Key parameters, including mean crushing force, absorbed energy, and crush force efficiency, were evaluated. The corresponding deformation patterns from both experimental and simulations were compared. Findings: Increasing the drop height led to higher impact velocities, resulting in greater absorbed energy, higher crushing forces, and more pronounced progressive folding patterns. The force–displacement (F-D) responses consistently exhibited an initial buckling (primary peak) stage followed by a progressive folding (plateau) stage; with the onset of densification observed only at the highest drop height (3 m), confirming the stable absorption behaviour of the AA6060-T4 crash boxes. Higher drop heights promoted larger deformation strokes and increased crush force energy, thereby enhancing overall crashworthiness performance. Numerical results show good agreement with experiments. Research limitations/implications: The study is limited by geometric imperfections and simplified numerical assumptions. Future work should consider advanced material models and alternative structural designs. Practical implications: The study offers important insights into how impact severity affects crash box performance and serves as a useful reference for the design and optimisation of lightweight structures for automotive applications. Originality/value: The paper presents a combined experimental–numerical analysis of corrugated AA6060-T4 crash boxes across varying drop heights, offering new insights into crashworthy structure optimisation.