Mechanical performance of interpenetrating phase composites with multi-sheet lattice structures

•A novel multi-sheet lattice structure with interpenetrating phases was designed and fabricated.•Both quasi-static and dynamic mechanical properties of the IPCs were investigated.•The effects of several parameters were studied both experimentally and numerically.•The guidance for optimizing parameters under different loading conditions was provided. Interpenetrating phase composites (IPCs), as a novel type of composite material, offer advantages such as lightweight, high strength, and superior energy absorption. This study proposed a multi-sheet lattice structure based on the Gyroid surface, which was initially designed and then fabricated via TC4 laser powder bed fusion (LPBF). Through the infiltration of epoxy resin, a composite material with interpenetrating phases was achieved. Subsequently, the mechanical properties of the IPCs were comprehensively investigated using experimental and numerical simulation methods. In quasi-static compression tests, the IPCs demonstrated higher strength and improved energy absorption characteristics compared to original lattice structures. However, under dynamic loading conditions, while the strength of the IPCs showed significant enhancement, the improvement in energy absorption characteristics of the composite structures was constrained by temperature rise, thermal softening effects, and the glass transition of the epoxy resin induced by elevated temperatures. Thus, while the proposed IPCs exhibited high strength under both quasi-static and dynamic loads, it is imperative to consider material properties and the influence of temperature on energy absorption to prevent overestimation of performance under dynamic loading conditions. Therefore, this study not only highlights the novelty of utilizing a multi-sheet lattice structure based on the Gyroid surface for creating IPCs, but also underscores the importance of carefully considering temperature effects on material properties when evaluating their performance under dynamic conditions. [Display omitted]