The density ρf of the final Cu-foam was calculated by dividing the
mass of the foam by its volume, which was calculated based on Archimedes
principle. The porosity of the as-manufactured Cu-foam Pf can
be estimated by the equation Pf=1−ρf / ρCu, where ρf is the calculated
density of the foam and ρCu is the density of copper (ρCu=8.96 g/cm3).