Fabrication of porous aluminum alloy with aligned unidirectional pores by dipping pipes in base metal melt

A pure aluminum pipe was dipped into Al13 mass%Si melt at 873 K. After holding time, the specimen was cooled and solidified. With holding time shorter than 360 s, the pipe was connected with the base metal without melting of the inner wall. Aligned 37 pipes with internal diameter of 3mm were dipped into the base metal, also. Even the distance between the pipes was as small as 0.5 mm, the melt of the base metal penetrated among the pipes. The result of the EPMA analysis showed metallic bonding between the pipe and the base metal by Si diffused into the pure aluminum pipe side. It became possible by this method to fabricate porous aluminum alloys with aligned unidirectional pores by controlling the porosity, pore diameter and pore distribution.