Excellent Mechanical Properties and Energy Absorption of Hexagonal‐Body‐Centered Lattice Structure Fabricated by Selective Laser Melting

Abstract

Inspired by the crystal lattice characteristics of hexagonal‐close‐packed and body‐centered‐cubic metals, a novel hexagonal‐body‐centered (HBC) lattice structure is constructed for energy absorption. HBC lattice structures with three different c/a ratios are prepared by selective laser melting (SLM) using 316 L stainless steel powder. The geometric features and energy absorption performance of the fabricated HBC lattice structures with different c/a ratios are studied by scanning electron microscopy and quasistatic compression tests, respectively. The results show that the HBC lattice structure prepared by SLM not only exhibits good formability, but also demonstrates excellent mechanical properties and energy absorption capacity. The c/a ratio significantly affects the mechanical properties and energy absorption performance of HBC lattice structures. The Young's modulus, yield strength, and energy absorption increase as the c/a ratio decreases. Compared with other lattice structures, the HBC lattice structure exhibits better energy absorption at the same relative density, thus indicating the usefulness of the HBC lattice structure as a lightweight energy‐absorbing structure.