Numerical investigation on dynamic response of bio-inspired bi-directional corrugated lattice structure under impact loading

In order to explore the impact resistance of bio-inspired bi-directional corrugated lattice structure (BBCLS), ANSYS/LSDYNA finite element analysis software was used to establish the finite element numerical model under the impact load, and the existing test results were compared with the numerical simulation results to verify the effectiveness of the model. On this basis, the effects of different impact velocities on the stress distribution, deformation mode, bearing capacity and energy absorption characteristics of BBCLS were studied, and compared with the traditional body-centered cubic lattice structure (BCC). The effects of the geometric parameters such as amplitude, ripple number and cell wall thickness on the impact resistance of BBCLS were further analyzed using the numerical model. The results show that the carrying capacity, total energy absorption and specific energy of BBCLS under impact load are obviously superior to the traditional BCC lattice structure. The impact dynamic response of BBCLS is mainly related to impact velocity and microstructure geometry parameters. At low speed impact, BBCLS presents an overall deformation pattern. The structure changes to the local deformation mode during the impact of medium and high speed. With the increase of impact velocity, the increase of amplitude, ripple number and cell wall thickness can make the stress distribution of the structure under impact load uniform, and effectively increase the platform stress at the impact end. In addition, the change of microstructure geometric parameters has a significant effect on the specific absorption energy of the structure and the overall specific absorption energy. As the number of ripples increases, the bearing capacity, stiffness and energy absorption of BBCLS are greatly improved. When the number of ripples is 8, the impact velocity reaches 100 m/s. Compared with the number of ripples, the impact velocity is 10 m/s, which is 201.36% higher than the energy absorption. The results provide a mechanical basis for the study of impact deformation failure and energy absorption effects of bionic lattice structures.