A Novel Asymmetric Triangular Re‐entrant Honeycomb with Enhanced Energy Absorption

Traditional honeycombs commonly exhibit a single deformation mode and inferior deformation stability when applied to buffering and impact protection. To overcome these constraints, a novel asymmetric triangular re‐entrant honeycomb (ATRH) is proposed by combining an asymmetric re‐entrant honeycomb (ARH) with triangular structures. The accuracy of the finite element (FE) model is validated by comparing experimental results. By arranging the ATRH in different patterns, four novel negative Poisson's ratio honeycombs (ATRH‐1, ATRH‐2, ATRH‐3, and ATRH‐4) are proposed, and their mechanical performance is investigated through FE analysis along both the X‐ and Y‐directions. The results show that, along the Y‐direction, the arrangement of ATRH‐1 enables stepwise deformation of the structure, resulting in three energy absorption stages. Comparative analysis shows that ATRH‐1 is the optimal arrangement, and parametric studies are then conducted to examine how structural parameters affect mechanical performance. At a similar relative density, the specific energy absorption of ATRH‐1 is 82.6% and 79.5% higher than that of the re‐entrant honeycomb in the Y‐ and X‐directions, respectively. Overall, this work provides insights into the parametric design of ARH and offers novel ideas for the design of multistage energy absorbing structures.