Melting of SmBa2Cu3O7-y-seeds during preparation of YBCO Bulk Superconductors by Infiltration Growth Method

The conditions for single-grain growth of YBCO bulk superconductors by top seeded infiltration growth were tested. It is shown that the interaction of melt formed from BaCuO2 + CuO + Y2O3 precursor with the Sm123 seed causes dissolution of the seed at maximum melting temperature 1045 °C. Experiments with low weight Y211 pellet confirmed that the low concentration of Y in the infiltration melt is responsible for this effect. The most effective way suppressing the seed dissolution was shown to be the insertion of Y123 + Y211 buffer layer between the seed and the Y211 pellet. This buffer layer possesses the melt which is saturated with yttrium what prevents dissolution of the seed.