Superconducting Performance, Microstructure and SEM by EDX Analysis of IG Processed YBa₂Cu₃O_y Bulk Superconductors by Top and Interior Seeding Methods

The top-seeded and interior seeded methods, together with infiltration growth (IG) technique were used to produce YBa₂Cu₃O_y (Y-123) samples with Y₂BaCuO₅ (Y-211) secondary phase particles. T_c (onset) was around 91.5. K. When interior seeding process was used, a complete growth of Y-123 single grain starting at the lower part of the bulk was observed by optical microscopy. The Y-211 particles dispersion was quite uniform in lower and upper parts of the samples, both in the a- and c-axis growth sectors, both at the beginning and end of the grain growth. In the sample produced by infiltration growth and interior seeding the critical current density at 77 K with H//c-axis was 44,000 A/cm² and 7,750 A/cm² in self-field and 2 T, respectively. It is a good basis for optimization of processing conditions, which can further improve the superconductor's performance and enable to grow large-size Y-123 bulks.