The energy absorption mechanism of the aluminum foam-filled multi-cell conical tube under the oblique impact loading

Collision loads in actual safety accidents are complex, and the direction of loads on structures is uncertain. Therefore, it is of great significance to study the energy absorption mechanism of the protective structure under the oblique impact loading. In this paper, a kind of the aluminum foam-filled multi-cell conical (AFMTC) tube was designed and manufactured, and its finite element model was established and validated. Based on Complex Proportional Assessment (COPRAS) method and Radar graph, the influence of oblique impact loading (angle, speed and action point) on the energy absorption performance was studied, and the coupled energy absorption mechanism was revealed. It is found that the four-cell structure of AFMTC (AFMTC-N4) tube has the best anti-tilt performance and the overall energy absorption is stable when the impact angle is 0°∼20°. In addition, the change of action point shows insensitivity to the energy absorption characteristics. Finally, the coupled effect makes the deformation mode of the AFMTC tube regular and efficient, and the energy absorption effect is better.