Repeated foaming of A1050 porous aluminum with densification by compression and friction stir processing and remaining foaming agent

Abstract

Porous aluminum, which has many pores inside, is lightweight and has high shock absorption properties. However, once porous aluminum is impacted and deformed, the cell walls are collapsed and difficult to reuse. In this study, we attempted re-foaming of deformed porous aluminum using the undecomposed foaming agent remained during the porous aluminum fabrication process. In our previous study, it was found that porous aluminum can be re-foamed by compressing and densifying with FSP before optical heating. In this study, we attempted further foaming of refoamed porous aluminum by optical heating after densification by compression and FSP. The amount of foaming gradually decreased with each repeated foaming, and the pore structures were not the same as that of the initial foaming, but further foaming was achieved after re-foaming. From the XRD analysis, it was observed that the undecomposed foaming agent remained after re-foaming.