INFLUENCE OF RELATIVE DENSITY AND MICROSTRUCTURAL ANISOTROPY ON THE GLOBAL ELASTIC PROPERTIES OF CELLULAR STRUCTURES

Abstract

The favorable strength-to-weight ratio of cellular solids makes them ideal for structural applications. With the advent of additive manufacturing, the fabrication of complex cellular structures is becoming a reality. It is therefore necessary to understand the mechanical properties of cellular structures. The global mechanical properties of cellular structures are governed by geometry and therefore, differ from the mechanical properties of the base material from which they are constructed. In this study, finite element models are developed to explore the effective elastic properties of honeycomb structures for isotropic and anisotropic microstructural material properties. Finite element models are generated for regular, hexagonal honeycombs and irregular, Voronoi honeycombs to study the relationship between cell regularity and microstructural anisotropy. Lastly, the finite element models vary in relative density from purely solid to purely cellular to better understand the ranges of relative densities where a structure behaves as a cellular structure versus a porous solid. The results of the finite element analysis are compared to the theoretical solutions for regular, hexagonal honeycombs as well as the theoretical solutions for porous media. A recommendation is made to the theoretical analysis of honeycombs to improve correlation with the finite element results.