Phase Equilibrium And Epitaxial Relations Of Sm-Ba-Cu-O High Temperature Superconducting System

In this paper, we studied the epitaxial phases and their orientations on Sm211 single crystal whisker.We confirmed the long axis of sm211 whisker is [001] direction. Through the analysis on the growth mechanism of the low-energy surface, we improved the experiment and got a large scale Sm211 whiskerIn situ investigation experiments were performed with a high-temperature optical microscope on the (010) surface of Sm211 single crystal whisker. A needle-shaped high temperature phase was observed at 1085℃,which showed two epitaxial relations of 0°and 90°to the long axis of whisker. SEM, EDX and XRD analyses showed this phase may be the Sm242 phase. At peritectic temperature 1050℃, the Sm123 phase formed on the Sm211 whisker and showed two epitaxial relations of 0°and 45°. The experiment and thermodynamic analysis showed the 45°relation is more stable.Finally, we tentatively used the large scale Sm211 whisker as seed for the RE123 bulk melt-textured growth. The experiments showed polycrystalline growth and self-nucleation on the surface. Analyzed this result, we suggested some improving methods.