In-plane energy absorption characteristics and mechanical properties of novel re-entrant honeycombs.

This paper proposes novel re-entrant honeycombs (NREH), which are designed as the support ribs of the re-entrant honeycomb subunit in an asymmetrical form to further improve its mechanical properties. First, three types of NREH composed of asymmetric subunits are compared. The σ m and specific energy absorption (SEA) of the three NREHs are not much different during in-plane impact, while the Poisson's ratio of NREH-3 is smaller than that of the other NREHs. Analyze the performance of NREH-3 by analyzing the change of angle θ. It was found that in the y-direction, the SEA of NREH-3-80 is 41.46% higher than that of NREH-3-60, and the Poisson's ratio is almost unchanged. On x-direction, the energy absorption performance is not significantly improved. Analysis of NREH-3′s sensitivity to impact velocity revealed that NREH-3-60, NREH-3-70, and NREH-3-80 are greatly affected by impact velocity. As the velocity increases, their deformation models significantly change, while other structures remain constant. An analysis of the influence of NREH-3 on wall thickness showed that the SEA of NREH-3 is significantly improved with increasing wall thickness and that Poisson's ratio did not significantly change, indicating that appropriately increasing the wall thickness effectively improves the impact resistance of the honeycomb structure. [ABSTRACT FROM AUTHOR]