Studies On The Dynamic Mechanical Properties And Energy Absorption Of Aluminum Alloy Foams

Metal foams are a new, as yet imperfectly characterized, class of engineering materials with low densities and novel physical, mechanical, thermal and acoustic properties. The characteristics of a foam are best summarized by describing the material from which it is made, its relative density, ρ*/ρ_s (the foam density, p',by that of the solid material of the cellwall,ρ_s), and stating whether it has open or closed cells. Beyond this, foamproperties are influenced by structure, particularly by anisotropy and by defects-by which we mean wiggle, buckled or broken cell walls, and cells of exceptional size or shape. Recent improvements as well as the development of production methods for metallic foams have offered a variety of application in fields such as the automobile, railway and aerospace industries. In these applications, the foam is subject to high-velocity deformations. Designing for these applications therefore demands a full characterization of their mechanical properties under a wide range of strain rates. For these reasons, dynamic compressive behavior, the energy absorption and the strain rate sensitivity of aluminum alloy foams have become one of the most attractive topics. In this paper, combined with theoretical analysis and numerical simulation, the dynamic compressive behavior, deformation mechanism, energy absorption and strain rate sensitivity of aluminum alloy foam are studied systematically. The obtained results are outlined as following:1. The equivalent in-plane elastic parameters of two-dimensional square honeycomb are evaluated. A homogenization FEM is derived for the 2-D...