AN EXPERIMENTAL STUDY OF THE INDENTATION BEHAVIOUR OF Al FOAM

Article history: Received: 31.01.2013. Received in revised form: 08.02.2013. Accepted: 08.02.2013. The indentation response of a closed-cell Al foam under the flat-end cylindrical indenter was experimentally investigated. The effects of indenter sizes, relative density of Al foam and boundary condition on the mechanical and energy absorption characteristics of indentation were also investigated. Experimental results show that the indentation load-displacement response obtained using the flat-end cylindrical indenter is similar to that observed under uniaxial compression. Crosssectional views of the indented specimens show that the deformation is confined only to the region directly under the indenter with very little lateral spread, and that the indentation deformation of Al foam is non-uniform. The tear energy and energy absorbing efficiency of Al foam is not related with the indenter diameter and relative density of Al foam. By increasing the indenter diameter or decreasing relative density, the indentation hardness is linearly decreased, but the energy absorbing capability linearly increases with an increase in indenter diameter or an increase in relative density. At a certain indentation depth range, the difference between rigid foundation and the indentation response of Al foam under simply supported conditions can be ignored.