The effect of axial crucible rotation on microstructural uniformity during horizontal directional solidification

Abstract The effects on microstructure of crucible orientation with respect to the Earth's gravitational vector, g , during directional solidification of low-volume fraction copper and aluminum, Pb-Cu, and Sn-Al alloys are examined. It is demonstrated that horizontal alignment (i.e. perpendicular to g ) in combination with axial rotation of the crucible during growth is sufficient to negate factors which initiate macrosegregation, e.g. density gradients attributed to temperature and/or compositional differences, and promotes a uniform microstructure.