A study of the impact dynamics of improved arc-edged concave honeycomb

To enhance the impact resistance and energy absorption capacity of honeycomb structures, this study proposes two Improved Arc-Edged Concave Honeycomb structures (IAEC-I and IAEC -II). These structures are developed through geometrical topology optimization, incorporating a thin-walled cylindrical structure into the traditional Arc-Edged Concave Honeycomb structure (AEC) and substituting its horizontal wall with a double-crossed sloping wall. The deformation mechanisms, auxetic properties, and energy absorption characteristics of the two improved structures under different impact velocities and relative densities are systematically investigated using Abaqus/Explicit finite element analysis software. Additionally, the influence of geometrical parameters on energy absorption performance is analyzed. The results demonstrate that the introduction of the circular thin-walled structure enables the IAEC honeycomb to retain the negative Poisson’s ratio effect of AEC while significantly enhancing its impact resistance and energy absorption efficiency. At different impact velocities, the average nominal stress and specific energy absorption of IAEC-I and IAEC-II are both greater than those of AEC. Specifically, at impact velocities of 3m/s, 20m/s, and 120m/s, the platform nominal stress of IAEC-I increased by 66.8%, 87.5%, and 8.7%, respectively, while the platform nominal stress of IAEC-II increased by 65.9%, 58.1%, and 5.1%, respectively. The specific energy absorption of IAEC-I increased by 56.1%, 83.9%, and 15.9%, respectively, while that of IAEC-II increased by 50.8%, 61.8%, and 19.6%, respectively. In addition, the present study explores the effects of impact velocity and relative density on the stress of the IAEC honeycomb platform. In light of the exploratory results, an empirical prediction model for platform stress is formulated. Finally, a comprehensive summary of the regulatory effects of geometric parameters on the energy absorption characteristics of honeycomb structures is provided through parametric analysis. The research results can provide new ideas for the design and application of high-strength, high-energy-absorbing honeycomb structures.