Enhancing impact resistance of hybrid structures designed with triply periodic minimal surfaces

The triply periodic minimal surface (TPMS) represents an engineered structure characterized by its mathematically controllable geometric topology and exceptional mechanical properties. This structure offers notable features such as high porosity, specific strength, stiffness, and energy absorption capabilities. Drawing inspiration from the structure of the human tibia, we developed hybrid structures that combine side-by-side, circular, and elliptical connections, utilizing two TPMS types: IWP and Gyroid. Our comprehensive study delves into the impact resistance of these hybrid structures when subjected to high strain rate loading. To conduct our research, we employed selective laser melting (SLM) to fabricate TPMS samples based on AlSi10Mg, and we validated our finite element model through quasi-static compression experiments. By conducting numerical simulations, we analyzed the mechanical properties and deformation patterns of these structures under strain rates of 250s−1 and 1250s−1, comparing them to commonly used porous structures such as Honeycomb, FCC, and BCC. Through quantitative analysis utilizing various evaluation indexes, we effectively demonstrated how the design of hybrid structures enhances energy absorption. Furthermore, we discussed the impact of strain rate on the mechanical properties of these structures, and the Gibson-Ashby model accurately predicted the mechanical properties of partial structures. These findings hold significant implications for guiding the design of lightweight porous structures, improving energy absorption, and enhancing impact resistance.