Mechanical Behaviour of Metallic Hollow Spheres Foam

Structural and mechanical characterization of stainless steel hollow spheres foams has been investigated by X-ray tomography. In-situ compression tests enable to study the main deformation mechanisms that govern the plasticity of the foam. FEM calculations of the compression of a pair of connected spheres have been performed in order to identify the conditions under which either mechanism is operative. Then a macroscopic phenomenological model for the compressive behaviour has been developed. It describes the overall behaviour of the material following damage progression. The model gives a description of an equivalent homogeneous material without loosing information on irreversible mechanisms occurring at the level of the mesostructure.