The effects of cooling velocity, melt weight and purity of copper were reported on copper single-crystal growth by Heat Exchanger Method in this paper. Copper single-crystals could be grown at the cooling velocity lower than 1℃/min. Higher purity(99.995wt%) of copper single crystal less than 7㎝ height(radius 3.5㎝) was grown when the cooling velocity was 0.34℃/min. and the height less than 3.5㎝(radius 3.5㎝) was grown with the plane front of solid-liquid interface and of semi-ellipse, and the free surface of single crystal was solidified in the end. However in the lower purity(99.93wt%) of copper, it should be solidified with plane front at the initial stage, and cell, dendrite formed finally at the cooling velocity lower than 0.5℃/min. The significant segregation were caused when the solid-liquid interface was changed from plane front to cell structure. |
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