Abstract
Tin is effective for reducing the grain size of pure zinc castings, but on the contrary causes intergranular corrosion of the castings when more than 0.05% is added. The cast structure of Zn-0.05%Sn alloy solidified in stirring was investigated. To observe the effects of stirring on the movement of liquid, a solution of water and 60% glycerin with 66 nylon balls were stirred in an acryl vessel at various conditions. The results obtained are as follows. Granular crystals that had separated accumulated at the bottom of vessel when the effects of stirring on the water or solution were not observed at the bottom of vessel. But columnar crystals were seen to develop from the bottom of vessel when they were indicating, stirring at 2∼3s-1 was effective for reducing grain size.
