Metals foams, also called cellular or porous metals, combine favorable metallic properties with a low density. Although metal foams are often made through liquid-state foaming (mostly aluminum foams), solid-state foaming allows for unique processing benefits. For instance, the size and spacing of pores can be controlled and any metal or alloy can be “foamed.” In conjunction with researchers at ARL, we developed a method to create metal foams by reducing oxide particles within the metal particles. This allows foaming of individual particles as well as bulk components made from them. The process can be combined with other, well-established methods to create additional porosity. So far it has been successfully applied to copper, but other metals and alloys are in development now. I hope to advance an understanding of the mechanisms and to apply it to bulk part creation. The images below show the structure of the foamed material. To see a “video” of cross-sectional ion milling of a foamed particle, click here.
Related publications are listed below (for full list, see Publications).
This work is supported by the Division of Materials Research (DMR) through the Faculty Early Career Development Program (CAREER Award #1555016)
Publications on Solid-State Foaming:
- Mark A. Atwater, Kris A. Darling and Mark A. Tschopp. Synthesis, characterization and quantitative analysis of porous metal microstructures: Application to microporous copper produced by solid state foaming. AIMS Materials Science; 3(2), pp. 573-590 (2016)
- Mark A. Atwater, Kris A. Darling and Mark A. Tschopp. Solid-State Foaming by Oxide Reduction and Expansion: Tailoring the Foamed Metal Microstructure in the Cu–CuO System with Oxide Content and Annealing Conditions. Advanced Engineering Materials; 18 (1), pp. 83-95 (2016)
- Mark A. Atwater, Kris A. Darling, Mark A. Tschopp. Towards reaching the theoretical limit of porosity in solid state metal foams: Intraparticle expansion as a primary and additive means to create porosity. Advanced Engineering Materials; 16 (2) pp. 190-195 (2014)