Influence of solidification mode on pore structure of directionally solidified porous Cu-Mn alloy

By the directional solidification of metal-gas eutectic method (GASAR), porous Cu-Mn alloy with oriented pores was fabricated successfully. The variation of pore structure was studied by experiments. The results show that the pore structure is primarily dependent on the solidification mode (planar, columnar cellular, columnar dendritic, equiaxed dendritic), which is controlled by the solidification process. By numerical simulation, it is noted that along with solidification, the solidification mode of the alloy transforms from cellular to columnar dendritic and finally to equiaxed dendritic. Through increasing melt temperature and mold preheating, the range of equiaxed dendrite could be decreased, which helps to extend the region of oriented pore structure.