Uniaxial stress-strain behaviour of aluminium alloy foams

The tensile and compressive stress-strain behaviour of closed cell aluminium alloy foams (trade name "Alulight") has been measured and interpreted in terms of its microstructure. It is found that the foams are anisotropic, markedly inhomogeneous and have properties close to those expected of an open cell foam. The unloading modulus and the tensile and compressive yield strengths increase non-linearly with relative density. The deformation mechanisms were analysed using image analysis software and a d.c. potential drop technique. The scatter in results is attributed to imperfections within the foam. These include non-uniform density, weak oxide interfaces, and cell faces containing voids and cracks. (C) 1999 Acta Metallurgica Inc. Published by Elsevier Science Ltd. All rights reserved.