An Improved Multi‐Arc Enhanced Reentrant Honeycomb With Dual Energy‐Absorbing Plateaus and Tunable Poisson's Ratio Sign Reversal

Honeycombs have garnered significant research interest owing to their multifunctional attributes and exceptional mechanical performance. This study develops an improved variant of the multi‐arc enhanced reentrant honeycomb (MAERH) inspired by the multi‐arc reentrant auxetic honeycomb (MARAH). A combined experimental‐numerical methodology is employed to investigate the compression behavior of additively manufactured specimens under quasi‐static loading. The experimental data are provided for constructing and verifying the finite element models. A series of finite element analyses is systematically performed to determine the key parameters of the mechanical characteristics. Within the effective compression range before densification, Poisson's ratio ( ν ) can be regulated by adjusting the crossing angle α , and the variation law of the strain‐controlled ν transition varies with α . Moreover, the critical effective strain for the linkage contact (and the accompanying ν transition) can be tuned by adjusting the spacing of the installed connecting rods, which synchronously determines the onset strain of the second stress plateau. Compared to MARAH, MAERH shows a lower stiffness, which results in lower initial stress when the structure is compressed. Due to its two stress plateau stages and excellent stability, MAERH exhibits a 129% increase in specific energy absorption compared to MARAH. The MAERH introduces a revised structural design strategy that successfully reconciles the conflict between high stiffness and high energy absorption. The superior performance of MAERH offers new ideas for lightweight honeycomb metamaterial design.