Mechanical characterization of AlSi12 foams at high strain rates

Abstract

In recent years, there has been a rapid growth in the use of aluminium foams in engineering applications, and there is a clear indication that this will be continuing. In this context, a better knowledge about the mechanical properties of these materials is expected, especially when submitted to dynamic loads. The mechanical properties, in static terms, are conveniently reported in the open literature for uniform-size and dual-size open-cell structures, but studies about their characterization in terms of high strain rates are not so abundant. Therefore, in order to optimize the mechanical properties at high strain rates, these two types of open-cell aluminium foams are compared. For this purpose, dynamic tests are performed using a Split Hopkinson Pressure Bar (SHPB), and the stress-strain curves are analysed in detail. It is possible to conclude that aluminium foams with dual size present better energy absorption than the uniform-size ones.