Out-of-plane impact resistance enhancement in plane lattice with curved links

In the past decades, various novel functions (i.e., negative Poisson's ratio, zero thermal expansion) have been obtained by tailoring the microstructures of the cellular structures. Among all the microstructures, the horseshoe topology shows a J-shaped stress-strain curve, which is quite different from the conventional materials. It can be inferred that the 2D lattice structure with horseshoe microstructure will also exhibit excellent out-of-plane impact resistance since the spider silk also exhibits the J-shaped stress-strain curve. In this paper, the out-of-plane sphere impact of 2D truss lattice structure is conducted using finite element method (FEM) simulation. The point has been made that, by replacing the direct-line beam to horseshoe curved beam, the out-of-plane impact resistance has been greatly improved. The most curved beam structure is found to have the best out-of-plane performs with the maximum energy absorption and the minimum passing through velocity.