Quasi-static compressive properties of a novel shell-plate hybrid crystal lattice metamaterials

3D plate-lattice metamaterials (PLMs) exhibit exceptional specific stiffness; however, the synergistic enhancement of deformation stability and energy absorption remains an open challenge. To address this limitation, a novel shell-plate hybrid crystal lattice metamaterial (SPh-CLMs) is designed by integrating an FCC shell-lattice with a traditional SC plate-lattice framework. By replacing selected flat plates with curved shell elements, localized membrane-bending coupling is strategically activated, initiating a “constrained shell effect” that suppresses localized plate-type instabilities. The mechanical response under quasi-static compression is evaluated through selective laser sintering experiments and finite element simulations, focusing on the influence of the curvature parameter (θ). Results demonstrate that increasing θ markedly reduces stress fluctuation amplitudes while significantly enhancing load-bearing capacity and deformation stability. Specifically, at a relative density of 0.185, the initial yield stress, plateau stress, densification strain, and specific energy absorption are increased by 15.60%, 15.91%, 14.04%, and 33.02% for SPh-CLMs with θ = 30° compared to conventional FCC-SC plate-lattices, respectively. These findings demonstrate that localized curvature engineering offers a viable strategy for the concurrent optimization of energy absorption and mechanical stability, with promising implications for advanced lightweight structural and protective applications.