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Hollow silver particles with three different shapes, i. e., spherical, cylindrical, and octahedral, were used as raw material to produce open-cell silver foams. The shape difference of the particles resulted from the reduction of different shaped silver sulfates. Fabrication of silver foams was carried out using SDP process with disaccharide particles as space holder. The resultant silver foams show high porosity with distinctive pore microstructures. The examination of pore structure by SEM shows that there are three levels of porosities which are unique for each type of foam. The foams, using spherical and cylindrical silver particles, have a larger surface area and a higher density than the foam with the silver particle of octahedral shape. A control of pore architecture can be performed by tailoring material and process parameters. The difference in pore architecture resulted in a different compressive behaviour of the foams. As expected, the foam, using octahedral silver particles, has lower compressive strength than the others, mostly due to lower foam density.

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Silver foams with 70% porosity have been produced by the sintering and dissolution process (SDP) of fine silver powder. The powder was obtained from the reduction of rod-shaped silver sulfate, using glycerol mixed with sodium hydroxide as reducer and reaction accelerator, respectively. The foam shows three-level porosities, ranging from nanometer to millimeter level. The nanopores were created during the reduction process. The micropores were formed by the dissolution of remaining silver sulfate. The millipores were made from the removal of disaccharide powders. The pore architecture is unique and can be tailored by varying material and process parameters such as silver sulfate and disaccharide morphologies, reduction temperature and time as well as volume fraction of materials.