Additively-manufactured anisotropic and isotropic 3D plate-lattice materials for enhanced mechanical performance: Simulations & experiments

Plate-lattices are an emerging category of mechanical metamaterials with exceptional mechanical performance. In this paper, a family of half-open-cell plate-lattices is innovated with exceptional mechanical properties and additive manufacturability. The elastoplastic properties and large strain response of the novel plate-lattices are investigated both numerically and experimentally. Design maps for tailoring the anisotropic index reveal that elastically isotropic plate-lattices can be obtained for a wide range of relative densities. Numerical results reveal that the isotropic plate-lattices exhibit significantly higher elastic properties than other competing topologies such as conventional truss-lattices and isotropic smooth shell-lattices, and their bulk modulus can attain the Hashin-Shtrikman upper bound for all relative densities. Large strain simulations demonstrate the remarkable energy absorption capacity of the novel plate-lattices. The numerical findings are confirmed through the compression experiments on the anisotropic and isotropic stainless steel 316 L specimens manufactured by selective laser melting. This work proposes a novel type of plate-lattices with both exceptional mechanical performance and good additive manufacturability, which opens a new channel for the design of lightweight mechanical metamaterials.