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A first-of-a-kind, solid state process is used to foam loose metal powder to 40% porosity and bulk compacts to 70% porosity. Focused ion beam sectioning reveals expansion within individual particles and allows 3D digital reconstruction of the interior (shown in the inset images). The foamed particles are characterized by micron-sized, interconnected channels. The process is both simple and scalable. More details can be found in the article byMark A. Atwater and co-worker on page 190.