Deformation Modes And Energy Absorption Capability Of Honeycombs Under In-plane Impact

Hexagonal and circular honeycombs have stable plastic deformation modes and excellent energy absorption capability under in-plane impact, which are used to make energy absorption device generally. Analysis to honeycombs under impact is the basis of structure design, so it's required for people to study. In this dissertation, main deformation modes of honeycombs under in-plane impact are introduced and investigation status is summarized at home and abroad. A large number of simulations are done with the help of FEA code ABAQUS, the result agree well with the theoretical models.We have analyzed the dynamic behavior of hexagonal honeycomb, the influence of impact velocity, thick and the length ratio (t/l) and the impact direction to the deformation modes and energy absorption capability of hexagonal honeycomb. The result reveals that the ultimate deformation modes are both velocity and (t/l) dependent. Under X-axis direction impact, Hexagonal honeycomb appears "X" shaped deformation mode under a low velocity impact and "I" shaped deformation mode under a high velocity impact, and "V" shaped deformation is a transitional mode between "X" and "I" shaped deformation modes. Under Y-axis direction impact, honeycomb appears a simple "I" shaped deformation mode. Under different impact velocity, the initial location of the initial deformation is different. Through a large number of simulations, we get the empirical formula of critical velocity on three deformation modes.We have analyzed the dynamic behavior of circular honeycomb with three different arrange-square, vertical and transverse. Three different deformation modes appear in three different arranges. Use the shortest path theory of the stress wave propagation to explain the three different deformation modes appearance.Compare the energy absorption of the hexagonal honeycomb and the transverse arranged circular honeycomb with the same relative density, they have the similar energy absorption capability, although energy absorption capability of cylindrical honeycomb is better than hexagonal honeycomb...