Study on the load-bearing and energy absorption performance of additively manufactured plate–truss hybrid lattice structures

Inspired by the deep-sea glass sponge skeleton, this study designed and fabricated three hybrid lattice structures that combine face-centered cubic Z-strut (FCCZ) truss and plate architectures using selective laser melting (SLM): body-diagonal plate–truss hybrid lattice structure (structure A), square plate–truss hybrid lattice structure (structure B), and face-diagonal plate–truss hybrid lattice structure (structure C). These structures aim to address stress concentration at the nodes of conventional truss lattice structures and the tendency of conventional plate lattice structures to undergo global failure. The mechanical properties, energy absorption (EA) characteristics, and failure mechanisms of these structures are investigated through quasi-static compression tests and finite element simulations. The results demonstrate that unlike structures B and C, which undergo global failure under compression, structure A, featuring cross plates added at the body center, exhibits intersections between the internal plates and multiple struts, forming nodes that increase the number of load transfer paths. This configuration creates an efficient load-bearing network, effectively alleviates stress concentration, exhibits layer-by-layer fracture characteristics, and avoids global structural failure induced by shear bands. The specific ultimate strength and specific energy absorption (SEA) of structure A are 343.47 MPa/(g/cm3) and 166 J/g, respectively, which are considerably higher than those of structures B and C. Compared with existing TC4-based lattice structures, the proposed hybrid lattice structures exhibit higher specific strength and SEA. The findings of this study provide insights into the effective design and optimization of hybrid lattices and offer a feasible strategy for applications requiring lightweight and high-strength materials.