Oblique impact loading conditions are common in automobile collision accidents, which strongly influence the energy absorption performance of thin-walled structures. In this paper, a novel three-dimensional (3-D) hexagonal structure-filled crash box with better comprehensive crashworthiness under multiple working conditions is proposed. First, the finite element models of four 3-D typical cellular structures (hexagon structure, re-entrant hexagon structure, star-shape structure, double arrow structure) are established. The dynamic responses of four structures under different impact angles (from 0° to 30°) and impact velocities (from 5 to 15 m/s) are discussed. The results reveal that the 3-D hexagonal structure has great advantages in terms of the energy absorption at varying inclination angles. Second, the 3-D hexagonal structure is filled in the crash box in the form of gradient distribution. The multi-island genetic algorithm (MIGA) based on the response surface model (RSM) is utilized to explore the optimal design of crash box. Compared with the traditional crash box, the optimal 3-D hexagonal structure-filled crash box increases 18.9% in specific energy absorption and decreases 21.7% in maximum peak force, which demonstrates great potential for applications in impact engineering.

倾斜冲击载荷条件在汽车碰撞事故中很常见，这严重影响了薄壁结构的能量吸收性能。本文提出了一种新颖的三维（3-D）六边形结构填充碰撞盒，在多种工作条件下具有更好的综合耐撞性。首先，建立了四个3-D典型单元结构（六边形结构，凹角六边形结构，星形结构，双箭头结构）的有限元模型。讨论了四种结构在不同的冲击角（从0°到30°）和冲击速度（从5到15 m / s）下的动力响应。结果表明，在变化的倾角下，3-D六边形结构在吸收能量方面具有很大的优势。第二，3-D六边形结构以梯度分布的形式填充在碰撞盒中。利用基于响应面模型（RSM）的多岛遗传算法（MIGA）探索碰撞箱的优化设计。与传统的碰撞盒相比，最佳的3D六边形结构填充碰撞盒在比能量吸收方面提高了18.9％，在最大峰值力方面降低了21.7％，这显示了在冲击工程中的巨大潜力。