Simulation Study on Quasi-Static Compressive Mechanical Properties of Honeycomb Structures with Negative Poisson's Ratio

Negative Poisson's ratio structures are widely used in military, aerospace, vehicles, air-dropped packages, and medical devices due to their high strength, stiffness, energy absorption, and impact resistance, but their mechanical properties are significantly affected by geometric parameters. In this paper, for the compression energy-absorbing mechanism of the re-entrant hexagonal honeycomb structure, numerical simulations are used to study the effects of wall thickness and angular gradient on its compression failure mode and energy-absorbing performance. The results show that the wall thickness has little impact on the compression failure mode, while the angular gradient has a significant impact on the compression failure mode. The wall thickness has a significant effect on the energy-absorbing performance, and the larger the wall thickness is, the better the energy-absorbing property is; the energy-absorbing performance of the symmetric negative gradient structure is significantly better than that of the other three angular gradients, and all the four kinds of angular gradient structures have better energy-absorbing performance than that of the conventional re-entrant honeycomb. The results obtained provide a reference for improving the energy absorption performance of negative Poisson's ratio honeycomb structures under quasi-static compression.