Microstructure and Compressive Properties of Open-cell Silver Foams with Different Pore Architectures

Hollow silver particles with three different shapes; spherical, cylindrical and octahedral, were used as a raw material to produce open-cell silver foams. The shape difference in the particles resulted from the reduction of different-shape silver sulfates. Fabrication of silver foams was carried out using SDP process with disaccharide particles as a 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 from each type of foams. The foams, using spherical and cylindrical silver particles, have larger surface area and higher density than the foam with the silver particle of octahedral shape. A control of pore architecture can be performed through tailoring material and process parameters. The difference in pore architecture resulted in different compressive behavior of the foams. As expected, the foam, using octahedral silver particles, has lower compressive strength than the others, mostly due to lower foam density.