Fabrication of high-performance YBa₂Cu₃Oy melt-textured bulks with selective grain growth

Abstract

We developed a simple single-direction melt growth for the fabrication of high-performance REBa2Cu3O y (RE: rare earth element) melt-textured bulks with selective grain growth. In this method, bulks were epitaxially melt-grown from a large plate cut from commercial melt-textured bulks by utilizing the different peritectic temperatures of REBa2Cu3O y . Ag-added YBa2Cu3O y bulks with three crystallographic orientations ([100], [110], and [001]) were successfully prepared. The whole c-grown bulk showed a higher trapped field (∼0.39 T) with more circular distributions than the conventional top-seeded bulk. The proposed method is promising for the fabrication of high-performance melt-textured bulks with high scalability and flexibility.

Current Status of High Temperature Superconducting Materials and their Various Applications

“…As mentioned in Section 2.2, RE123 bulk materials have problems of very long crystal growth time and inhomogeneity in superconducting properties originated in two growth regions. The recently developed single-direction melt growth (SDMG) is a simple crystal growth method with high throughput and solving these problems [68]. In this method, large seed plates cut from commercial RE123 bulks are used instead of using small seed crystals in TSMG and TSIG methods.…”

Novel approach for manufacture of single‐grain EuBCO/Ag bulk superconductors via modified single‐direction melt growth

“…[18][19][20] Single-direction melt growth (SDMG) involves only single grain growth along the c direction and is a superior processing method compared to both TSMG and TSIG. 21,22 The pressed bulk precursor pellet is placed on top of a seed plate, which is commonly a (RE)BCO bulk single grain grown by TSMG with higher peritectic temperature. (RE)BCO bulk single grains grown by SDMG typically grow exclusively parallel to the direction c-axis as a direct result of this special seeding arrangement.…”

“…This enhances greatly the homogeneity of the trapped field and is crucial for particular applications of (RE)BCO bulk superconductors. 21 Additionally, the distance to seed within the bulk is constant within the a-b planes, which should improve the homogeneity of 211 inclusions within the bulk.…”

“…Single‐direction melt growth (SDMG) involves only single grain growth along the c direction and is a superior processing method compared to both TSMG and TSIG 21,22 . The pressed bulk precursor pellet is placed on top of a seed plate, which is commonly a (RE)BCO bulk single grain grown by TSMG with higher peritectic temperature.…”

“…Therefore, no growth sector boundaries are present in the as‐prepared single grains that may consequently deform the trapped field (Figure 1). This enhances greatly the homogeneity of the trapped field and is crucial for particular applications of (RE)BCO bulk superconductors 21 . Additionally, the distance to seed within the bulk is constant within the a‐b planes, which should improve the homogeneity of 211 inclusions within the bulk.…”