This work was aimed at analyzing and quantifying the influence of the degree of structural homogeneity of aluminum foams on their energy absorption properties. Specimens having the same relative density but with controlled degrees of heterogeneity were obtained by assembling in series several subsamples of constant density. These heterogeneous foams were tested under compression and their energy absorption properties analyzed by the use of specific energy absorption diagrams, which represent the real values of energy absorbed up to a certain value of stress -or strain-, normalized by the value of stress. Heterogeneous specimens showed mean values of collapse stress similar to the homogenous samples of the same density. However, the shape of the stress-strain curve was strongly modified, increasing the slope of the stress-strain curve and affecting the energy absorption behavior. Lower energy absorption efficiency and reduced specific energy absorption were also accompanied by modifications of the optimum peak stress and densification strain for the design of energy absorbing devices.
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