DIFFUSION SOLIDIFICATION MODEL ON Y-SYSTEM SUPERCONDUCTORS

The unidirectional solidification of the zone melt method was performed in order to clarify the growth mechanism on Y-system superconductors. A sharp faceted interface of YBa2Cu3Oy (123) crystals was obtained in the sample grown at the low growth rate of 1 mm/h. The volume of the 211 phase changed drastically from liquid to 123 crystal. These results lead to the idea that the necessary solute for peritectic reaction is provided through a liquid. Based on this idea, we developed a simple solidification model that is in good agreement with the experimental results.