Process Technology and Superconducting Properties of Bulk HTS With Multi-RE Elements
A series of REBa<sub>2</sub>Cu<sub>3</sub>O<sub>y</sub> (RE123)/Ag bulk superconductors with multi-RE elements at the RE site, were prepared by top-seeded melt growth. By employing the differential thermal analysis, we carefully adjusted the peritectic decomposition temperature (<i>T</i><sub>p</sub>) by changing the ratio of the two RE123 compositions to meet the requirements of the cold-seeding process. The superconducting properties, <i>T</i><sub>c</sub>, <i>J</i><sub>c</sub> and the flux trapping performance were evaluated after achieving the growth of the single grains. The microstructure was also observed. A relatively low growth temperature range depressed the LRE-Ba substitution, which was effective to suppress the probable RE211 coarsening. By employing ZrO<sub>2</sub> chemical doping, the flux pinning property was further improved under both zero-field and in-field, and the <i>J</i><sub>c</sub> was enhanced without reducing <i>T</i><sub>c</sub>.