Effects of holding temperature and holding time on pore structures in porous aluminum fabricated by friction stir processing

Porous aluminum has the advantages of good lightweight property and high specific strength. By applying porous aluminum as materials for automobile and structural component, both improvement of fuel efficiency and lightening can be realized. Authors have proposed the new fabrication method of porous aluminum using friction stir processing, i.e. Friction stir processing route (FSP route), which has low manufacturing cost and high productivity. Pore structure in porous aluminum depends on a holding temperature and a holding time when the blowing agent is foamed, and affects the mechanical properties. In this study, changing a holding temperature and a holding time, porous aluminum is fabricated by FSP route. Porosity of porous aluminum rises at short holding time when the holding temperature is high. Pore structures change even if the porosity is almost same and also changes quickly with the passage of holding time.