Modeling and observation of compressive behaviors of closed celullar structures using central Voronoi tessellation concepts

Abstract

Numerous numerical models of mimicking cellular structures have been proposed, but, in many cases, those models were not able to describe the random cell geometry which is common for most cellular products. The concept of Voronoi tessellation has recently applied to construct the random characteristics of cell structures, but the structure generated by classical Voronoi tessellation method is too ideal by comparing with the actual cell structures. Moreover, the verification of physical and mechanical behaviors of random cell structures is scarcely researched due to the complexity of fabricating the cell structures which are numerically generated. In this study, Central Voronoi Tessellation (CVT) theory which considers the center of mass of each cell for further iteration of cell structure modification is adopted to generate realistic shape of cell structures. Some key parameters such as relative density, anisotropy, and number of iteration are considered. Mechanical behaviors of samples with numerically generated cell structures are investigated using elasto-plastic finite element analysis considering instability conditions. In addition, test samples in some cases considered in FEA are fabricated by aluminum alloy using 3-D printer based on the selective laser melting (SLM) technique, and the test results are compared with the numerical simulation results.