Use of Mixed-Powder Buffers to Assist the Growth of SmBCO and ZrO2-doped SmBCO Single Grain, Bulk Superconductors

In this paper single domain, bulk SmBCO samples have been fabricated successfully in air in a top-seeded melt growth (TSMG) process using a conventional chamber furnace, in addition to samples doped with ZrO₂. To improve the reliability of seeding, Sm-123 + Sm-211 mixed-powder buffers were used to increase the success of the SmBCO single grain growth process. SmBCO single grains of diameter as large as 20 mm and 10 mm in thickness with and without ZrO₂ were fabricated successfully using Sm-123 + Sm₂BaCuO₅ (Sm-211) mixed-powder buffer layers. The geometric configurations of the buffers were also optimized as part of this study to further increase the success of the single grain growth process. Superconducting properties of J_C and T_C of the specimens under the buffer layer have also been investigated.