Fabrication of Porous Aluminum Alloys with Aligned Unidirectional Pores by Joining Pipes and Melt through Continuous Casting and their Mechanical Properties

Porous aluminum alloy was fabricated by joining pure aluminum pipes and base metal melt of Al-13mass%Si through continuous casting without breakout at transfer velocity of 155 mm/min. The position, volume fraction and diameter of pores were controlled by the initial setting position and geometry of pipes. The yield strength of fabricated porous aluminum alloy agreed well with the value calculated by the rule of mixture of pure Al and Al-Si alloy. The increment of the compressive stress of the fabricated porous aluminum alloy was small at high stress region by buckling of cell walls. This lowered stress resulted in the high efficiency of energy absorption. The pipes did not detach from the base metal even at high strain.