Compressive behaviour and vibration characteristics of Closed Cell Eutectic Aluminium Silicon Alloy foam

Abstract

Metal foams are a new class of materials with low densities, good vibration, acoustic properties, energy absorption and high specific stiffness. These also exhibit many unusual combinations of physical and mechanical properties that make them attractive in a number of engineering applications. Metallic foams can be manufactured by many methods like powder metallurgy route, melt route, gas injection into molten metal, liquid metal infiltration. The properties of metal foam depend on many morphological features, such as pore size distribution, cell wall curvature, defects etc. The aim of the present work is to study the compressive behaviour and damping properties of eutectic Al-Si alloy. Closed cell foam specimens were produced by melt route using calcium carbonate as foaming agent. The compressive test was conducted and stress verses strain curve exhibits a typical three regions, elastic, plateau and densification. Damping properties of closed cell were measured by experimental modal analysis using impulse excitation technique at room temperature.  Material damping factors were calculated by circle fit method. The measured loss factor shows that closed cell eutectic Al-Si alloy foams have a higher damping capacity compared to Al-Si alloy