Design ideal shock-absorbing metamaterials with sequential plastic buckling

An ideal shock-absorbing material should be lightweight, stiff before impact, and maximum dissipative upon impact. To date, shock-absorbing structures are either stiff and strong before impact or energy-absorbing upon impact, and normally can be only used once for the stiffness loose after the first impact. Metamaterials have emerged as a promising avenue for shock absorption since their programmable deformation. Here we strategically use plastic buckling to create metamaterials that can buckle sequentially in an arbitrary large number of steps, behaving as ideal and reusable shock absorbers. We demonstrate this approach in 2D, 2D axisymmetric, and 3D metamaterials and show how they perform as ideal and reusable shock absorbers. Our work expands the metamaterial toolbox of using plasticity and opens the door for their use in automotive and aerospace fields