Structural design and crashworthiness analysis of axial cutting coupled radial extrusion tube

In order to address the energy absorption (EA) issue caused by limited installation space, a circular tube EA structure with axial cutting coupled radial extrusion (ACCRE) deformation modes is proposed and constructed. The FE model of cutting and extrusion die, bottom plate, cross rib and circular tube was established. The accuracy of the FE model was verified by two repeated tests. Finally, the peak force was predicted by theoretical model. Under the influence of dies, the circular tube produces chips and grooves and exhibits multi-level EA characteristics, with specific EA of 43.38 kJ/kg and first and second order platform force of 107.53 kN and 515.22 kN. With a maximum error of only 6.78 %, the FE model and experimental data offer accurate simulations of deformation patterns, steady-state loads, and EA. The specific EA of the ACCRE tube is increased by 120.2 % and 223.7 %, respectively, when compared to the single deformation modes of cutting and extrusion. This finding indicates that the ACCRE deformation mode can adequately cause the tube to undergo plastic deformation, improve the material utilization rate to better EA effect.