Abstract
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 TiH2 or ZrH2 as a blowing agent. Foams with about 85% porosity are obtained.
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Experimental work was carried out at the Fraunhofer-Institute for Manufacturing Technology and Applied Materials Research, Bremen, Germany
About the author John Banhart is a professor in the Faculty of Materials Science and Technology at the Technical University of Berlin and head of the Department of Engineering Materials of the Helmholtz Centre for Materials and Energy (formerly Hahn-Meitner-Institute) in Berlin. Current research interests are aluminium alloys, metal foams and Xray and neutron imaging methods. He is a physicist and earned his PhD in physical chemistry at the University of Munich in 1989. He worked at the Fraunhofer-Institute in Bremen for 10 years where a process for foaming metals was developed in close cooperation with industry.
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Banhart, J. Gold and Gold Alloy foams. Gold Bull 41, 251–256 (2008). https://doi.org/10.1007/BF03214878
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DOI: https://doi.org/10.1007/BF03214878