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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 TiH2 or ZrH2 as a blowing agent. Foams with about 85% porosity are obtained.


  1. J. Banhart and D. Weaire,On the road again — metal foams find favour, Physics Today, 2003,55, 37–42

    Google Scholar 

  2. M.F. Ashby, A.G. Evans, N.A. Fleck, L.J. Gibson, J.W. Hutchinson and H.N.G. Wadley, Metal foams — A design guide, Butterworth-Heinemann, Boston (2000)

    Google Scholar 

  3. J. Banhart, Manufacture, characterisation and application of cellular metals and metallic foams,Progress in Materials Science, 2001,46, 559–632

    Article  CAS  Google Scholar 

  4. L.-P. Lefebvre, J. Banhart, D. Dunand, Porous metals and metallic foams — current status and developments,Advanced Engineering Materials, 2008,10, 775–787

    Article  CAS  Google Scholar 

  5. H.P. Degischer and B. Kriszt, Handbook of cellular metals, Wiley-VCH, Weinheim (2002)

    Book  Google Scholar 

  6. F.C. Meldrum and R. Seshadri, Porous gold structures through templating by echinoid skeletal plates,Chemical Communications, 2000, 29–30

  7. J. Erlebacher, M.J. Aziz, A. Karma, N. Dimitrov, and K. Sieradzki, Evolution of nanoporosity in dealloying,Nature, 2001,410, 450–453

    Article  CAS  Google Scholar 

  8. O.D. Velev, P.M. Tessier, A.M. Lenhoff, E.W. Kaler, A class of porous metallic nanostructures,Nature, 1999,401, 548–548

    Article  CAS  Google Scholar 

  9. K. Nagai, D. Wada, M. Nakai, T. Norimatsu, Electrochemical fabrication of low-density metal foam with mono-dispersed-sized micro and submicrometre pore,Fusion Science and Technology, 2006,49, 686–690

    CAS  Google Scholar 

  10. J. Banhart, Metal foams: production and stability,Advanced Engineering Materials, 2006,8, 781–794

    Article  CAS  Google Scholar 

  11. J. Banhart, D. Bellmann, and H. Clemens, Investigation of metal foam formation by microscopy and ultra small-angle neutron scattering,Acta Materialia, 2001,49, 3409–3420

    Article  CAS  Google Scholar 

  12. A. Irretier and J. Banhart, Lead and lead alloy foams,Acta Materialia, 2005,53, 4903–4917

    Article  CAS  Google Scholar 

  13. H.D. Kunze and M. Knüwer, About the foamability of iron — carbon alloys,Steel Research, 1999,70, 513–518

    CAS  Google Scholar 

  14. C.J. Yu, H. Eifert, J. Banhart, and J. Baumeister, Metal foaming by a powder metallurgical method: production, properties and applications,Journal of Materials Research and Innovations 1998,2, 181–188

    Article  CAS  Google Scholar 

  15. C. Körner, M. Arnold, and R.F. Singer, Metal foam stabilization by oxide network particles,Materials Science and Engineering A, 2005,396, 28–40

    Article  Google Scholar 

  16. A. Dudka, F. García-Moreno, N. Wanderka, J. Banhart, Structure and distribution of oxides in aluminium foam,Acta Materialia, 2008,56, 3990–4001

    Article  CAS  Google Scholar 

  17. B. Matijasevic, J. Banhart, S. Fiechter, O. Görke, and N. Wanderka, Modification of titanium hydride for improved aluminium foam manufacture,Acta Materialia, 2006,54, 1887–1900

    Article  Google Scholar 

  18. V. Gergely, D.C. Curran, and T.W. Clyne, The FOAMCARP process: foaming of aluminium MMCs by the chalk-aluminium reaction in precursors,Composites Science and Technology, 2003,63, 2301–2310

    Article  CAS  Google Scholar 

  19. B. Predel, Au-Si (gold-silicon), Landolt-Börnstein — New Series, Group IV Physical Chemistry, Vol. 5a, Springer-Verlag (1991)

  20. T.B. Massalski, Binary Phase Diagrams, ASM Information Society, Materials Park (1986)

  21. S. Mechler, Private communication (2008)

  22. D.M. Jacobsen, S.P.S. Sangha, A low melting poind solder for 22 carat yellow gold,Gold Bulletin, 1996,29, 3–9

    Google Scholar 

  23. C. Cretu and E. van der Lingen, Coloured gold alloys,Gold Bulletin, 1999,32, 31–40

    Article  Google Scholar 

  24. C.W. Corti, Blue, black and purple! The special colours of gold, 5th International Jewellery Symposium, St. Petersburg, 3. July 2006

  25. B. Matijasevic and J. Banhart, Improvement of aluminium foam technology by tailoring of blowing agent,Scripta Materialia, 2006,54, 503–508

    Article  CAS  Google Scholar 

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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).

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  • Foam
  • Aluminium Foam
  • Gold Alloy
  • Metal Foam
  • Titanium Hydride