Geometrical convergence was tested by comparing the measured
porosity of the Cu-foam sample with the volume porosity of the corresponding
3D model (i.e. deviation b2%). The reconstructed 3D models
of the Cu-foams used together with the pore size distribution obtained
from image analysis are shown in Fig. 3. Considering that the foam's
pores were open, a watershed algorithm was applied to convert the
open pores to closed ones. Each pore was then replaced with the best
fitting ellipse that had the same volume, orientation and centroid as
the original pore. Then, the mean size and pore size distribution were
calculated.