Gold and Gold Alloy foams

The possibilities to manufacture gold-based foams are explored. Gold powder and various powdered alloying elements are mixed with a small volume fraction of a gas-releasing blowing agent. The blend is compacted to a dense precursor, which is then melted in a further step in order to trigger foam formation. We find that gold-silicon alloys containing 2–3 wt.% of silicon or around 8 wt.% of germanium can be foamed using TiH 2 or ZrH 2 as a blowing agent. Foams with about 85% porosity are obtained.