Analysis of the morphology and chemical composition at the growth front of YBCO bulks

Abstract

The morphology and chemical composition at the growth front of YBCO bulks have been investigated to make clear the stopped growth mechanism in the samples which have covered the whole melt growth process. It is found that the breakdown of quasi-single crystal growth occurs when the liquid phase ahead of the growth front becomes rich in copper and depleted in yttrium and barium. To meet the needs for maintaining the continuous growth of YBCO, the composition of Y, Ba and Cu has to be adjusted to be rich in yttrium and barium in the liquid phase ahead of the growth front during the melt growth process for growing large YBCO bulk superconductors.