In-plane crushing behaviors of hexagonal honeycombs with different Poisson's ratio induced by topological diversity

Abstract

For the topological diversity, in-plane hexagonal honeycombs show some interesting mechanical properties which can be related to Poisson's ratios. This work trying to understand how Poisson's ratios affects the crashworthiness of in-plane honeycombs. Based on the standard beam theory, the analytical model that predicting Poisson's ratios is derived, from which the crushing strength in terms of Poisson's ratios is further proposed by using one-dimensional shock model. Combining the analytical and numerical method, Poisson's ratios on the critical crushing characteristics as plateau stress, densified strain, Specific Energy Absorption (SEA) has been investigated under crushing speeds range from 5 m/s to 150 m/s which is complied with previous study about in-plane honeycomb crashworthiness. Through observing the wave trapping behavior of honeycombs, some typical deformation modes have been identified and a deformation-mode map is generated by considering critical wave trapping speeds and Poisson's ratio.