The body-centered cubic (BCC) lattice structure is a commonly porous scaffold in automotive transportation and aerospace fields due to its lightweight and multiple functional characteristics, and there is a need to improve the ratio of compressive property-to-weight to save material consumption. In this study, inspired by the hollow cylindrical structure of rice stem and the porous spherical structure of Haeckel, the modified hollow-body body-centered cubic lattice structure (HBCC) and spherical-body composite body-centered cubic lattice structure (BBCC) with uniform porosity were designed and fabricated by selective laser melting (SLM) technology. Additionally, the CoCrFeMnNi high entropy alloy (HEA) was selected due to its good comprehensive performance. The compressive strength and energy absorption characteristics were comparatively investigated. The results show that the HBCC structure demonstrates a 104.7% increase in the strength, while the BBCC structure shows a 9.2% improvement, compared to the original BCC structure. The energy absorption capacity of HBCC and BBCC structures is significantly higher than that of BCC structures, increasing by 105.1% and 51.1%, respectively. These improvements are attributed to the effective release of stress concentration in the node of the original BCC lattice structures. Finite element (FE) numerical simulations and deformation observations also confirmed the alleviation of the stress concentration. This proposes a feasible design approach for lightweight HEA lattices in a variety of applications.
Sun et al. (Wed,) studied this question.