Cover Picture: The Role of Oxidation During Compaction on the Expansion and Stability of Al Foams Made Via a PM Route (Adv. Eng. Mater. 6/2006)

The foam expansion and collapse behaviour for hot compacted Al‐TiH₂ precursors has been shown to be driven by the oxidation of the Al powder and the premature loss of gas from the TiH₂ foaming agent during the compaction process. At 550 °C, oxidation is rapid, and gas loss from the hydride is extensive leading to poor expansion.