Enhanced energy absorption in star-shaped honeycomb structures through the negative poisson’s ratio effect

Abstract Star-shaped honeycomb (SSH) structures exhibit broad application potential in impact protection by the negative Poisson’s ratio (NPR). However, existing research has primarily focused on conventional structures with positive Poisson’s ratios (PPR), leaving the performance of NPR effects in SSH, particularly in combination with other materials, insufficiently explored. This study aims to investigate the NPR effect in SSH structures by systematically analysing the influence of varying Poisson’s ratios on energy absorption performance through wall angle adjustments. Results indicate that the NPR effect significantly enhances the specific energy absorption of SSH. Furthermore, in the coupling system of SSH filled with shear-thickening fluid, the NPR effect further augments energy absorption and establishes a stable energy dissipation mechanism under dynamic impact conditions. This study provides theoretical and experimental support for the application of SSH structures in impact protection and introduces an effective strategy for designing energy-absorbing structures through SSH-STF coupling.