Energy absorption properties of cellular materials with maximum bulk modulus

摘要

Cellular materials possess excellent mechanical, physical and thermal properties compared to solid materials. They are widely used as an energy absorber in the form of packaging foams to protect products from severe acceleration and deceleration in collision or impact events. The properties of cellular materials rely on their solid distribution within their periodic unit cell. In the last few decades, a large amount of research and studies have been conducted on metallic foams, honeycombs, and other cellular composites. However, only limited amount of research has been conducted on the 3D periodic cellular structures. Particularly, the practical research for the relationship between the specific energy absorption and bulk modulus of a 3D periodic cellular materials is the main concern. The cellular materials with optimized bulk modulus are expected to have merits for use in energy absorption applications. Unfortunately, there is few research conducted to investigate this type of materials. The aim of this thesis is to understand the specific energy absorption, compressive strength and deformation pattern of the 3D periodic cellular materials with optimized bulk modulus, i.e., Schwarz Primitive Structures, which possesses optimal mechanical, thermal and flow properties. Inspired by their optimum bulk modulus, this study aims to investigate the energy absorption capacity of 3D periodic Schwarz primitive structure under uniaxial compression as well as under triaxial compression. The experimentally validated Finite Element Models (FEM) is employed to simulate their deformation features. The mechanical properties of 3D periodic Schwarz primitive structure are studied in uniaxial and hydrostatic compression with strain control. The deformation process and corresponding stress-strain curves are presented. The nonlinear increasing trend of mechanical properties with respect to relative density has been obtained. The specific energy absorption of the 3D periodic Schwarz primitive structure. The merits of energy absorption capacity of 3D periodic Schwarz primitive structure under compression is confirmed by comparison with other common cellular material of identical relative density. It can be concluded from those results that the cellular materials have the ideal energy absorption features under uniaxial compression and have superior energy absorption capacity under triaxial compression. Thus, they are ideal for industry packaging and other energy absorption applications.