Directional solidification of Y123 thin fiber with different growth rates

Crystal growth of the YBa 2Cu 3O x superconductive oxide was investigated using the zone melting process. YBa 2Cu 3O x rods with 0.5 mm in diameter were unidirectionally solidified at different growth rates. Continuously grown single faceted structures were observed near the interface in the specimens grown at the grown rates up to 6 mm/h. The maximum growth rate to obtain a single faceted grain becomes higher in thin fibers. Although a single faceted continuous structure was observed near the interface of the specimen grown at 6 mm/h, discontinuous structures were observed in the sample. The compositional analysis revealed that the liquid composition near the growth interface of the sample grown at 6 mm/h was shifted to the CuO rich side. This compositional shift during solidification would be the reason for the break down of the continuous growth of YBa 2Cu 3O x crystals.