Crashworthiness and Failure Mechanism Regulation of 3D-Printed Gyroid Lattice Coupled with Column Struts

To improve the crashworthiness, the 3D-printed Gyroid lattices coupled with column struts are designed to regulate the failure mechanism by synergistic effects. There are four types of combining form to reveal their different synergistic effects, including Gyroid lattice with side column, Gyroid lattice with diagonal column, and Gyroid lattice with topology-optimized (TO) column. To improve Gyroid lattice with TO column, both gradient and nongradient column structs are further optimized. All samples are fabricated using fused deposition modeling rapid prototyping technique, and the typical 3D-printing defects are characterized to confirm their usability. By the axial crushing tests, the load–displacement responses, energy absorption, and failure mechanisms are evaluated. The results show that the significant improvements in the load-bearing and energy absorption are identified for the Gyroid lattice with diagonal column strut and TO-column struts, compared with pure Gyroid lattice. Under the synergistic effects, the failure mechanisms of Gyroid lattice with different column struts vary significantly, presenting a great effect on crashworthiness. The failure regulation mechanisms of Gyroid lattice induced by different single-column struts are revealed extensively. This work provides an effective guide for the lightweight crashworthiness design of complex coupling structures.