Structural response and energy absorption assessment of corrugated wall mechanical metamaterials under static and dynamic compressive loading

Mechanical metamaterials, especially corrugated wall structure with negative Poisson's ratio, have received much attention since it offers more options for energy absorption. Herein, the effects of structure factors, wall thickness, and gradient design on the structural response and energy absorption performance of corrugated wall metamaterials have been explored using finite element simulations, quasi-static compression tests and dynamic plate-impact tests. The energy absorption performance was evaluated using indexes such as energy absorption efficiency, specific energy absorption, plateau stress, etc. The results show that the difference in the deformation and interaction mechanism between corrugated walls leads to different mechanical responses of the structure. Compared with the normal sample, the gradient setting of the wall thickness (t) increases the negative Poisson's ratio by 44.6%, and the gradient setting of the structure factor (h/L) increases the maximum energy absorption efficiency to 80.52% (an increase by 14.7%). Finally, plate-impact tests demonstrate that the corrugated gradient structure has better energy dissipation performance than the corrugated normal structure. Compared with the normal sample, the thickness gradient sample and the structure factor gradient sample reduce the impact load of the structure by 42.89% and 34.56%, respectively. This work can strengthen our capability of engineering tunable energy-absorbing device for a wide range of application.