Pb-20wt%Cu 합금의 일방향 응고시 Cu 수지상 결정성장에 대한 시험편의 회전효과

The Effects of Sample Rotation on Cu-Dendritic Growth During the Directional Solidification of Pb-20wt%Cu Alloy

For Pb-20wt%Cu alloys, severe macrosegregation due to density difference of the resulting phases in normal directional solidification has been minimized and a uniformly aligned dendritic structure has been produced by axially rotating the sample of 5mm diameter in conjunction with horizontal directional solidification. Under the constant growth velocity of $20{\mu}m/sec$, increasing the rotation rate from 0.18 to 12rpm results in a transition from an aligned columnar to an equiaxed Cu-dendritic structure. With a constant rotation rate of 0.18rpm, increasing the growth velocity from 10 to $50{\mu}m/sec$ also has promoted a transition from columnar to equiaxed structure.