Enhancement of Energy Absorption Capability of 3D Printed Ti-6Al-4V BCC Lattice Structures by Adding Auxiliary Struts

Lattice structures, composed of interconnected struts, offer an efficient way to reduce structural weight while maintaining structural integrity. Because of this potential, this work aims to investigate and develop an efficient variant form of a BCC (Body-Centered Cubic) lattice structure to enhance the structural robustness and energy absorption capability, based on the Maxwell stability criterion. And we specifically changed the bending-dominated to stretching-dominated behavior by adding auxiliary struts, according to the theory, and confirmed how this affects the compression behavior of the structure. For this purpose, horizontal auxiliary struts are added for the first time to the BCC structure along with vertical struts. As a macroscale cellular lattice structure, a unit cell size of 12 mm is considered. For the considered macroscale cellular lattice structures, FEA (finite element analysis) is employed to numerically investigate the stress distribution and compressive deformation mechanisms. Then, quasi-static compression tests are carried out to measure the energy absorption performance of the lattice structures manufactured by the EBM (Electron Beam Melting) metal additive manufacturing technique, which has advantages in building lattice structures without supporters. A comprehensive investigation reveals that a newly designed lattice structure offers significant advantages in structural robustness, with energy absorption capability increased by 365% compared to existing structures, achieved by incorporating vertical and cross-shaped horizontal auxiliary struts into the original BCC lattice configuration. The enhanced lattice structures can be utilized in industries where low-weight and high-strength are needed, such as aerospace, marine, and other industries.