Development of homogeneous and high-performance REBCO bulks with flexibility in shapes by the single-direction melt growth (SDMG) method

TL;DR

This paper introduces a single-direction melt growth method for producing high-performance, shape-flexible REBCO superconducting bulks with homogeneous properties and high trapped magnetic fields, suitable for various applications.

Contribution

The study presents a novel SDMG technique enabling the fabrication of diverse-shaped REBCO bulks with high reproducibility and superior magnetic trapping performance.

Findings

YBCO bulk trapped over 1 T at 77 K

Homogeneous and boundaryless crystal structures achieved

Successfully fabricated various shapes with well-connected joints

Abstract

We have developed a single-direction melt growth method in which REBCO melt-textured bulks grow only vertically from a seed plate utilizing the difference in peritectic temperatures of REBCO. Entirely c-grown YBCO, DyBCO and GdBCO bulks with various sizes and shapes were successfully fabricated with high reproducibility. Disk-shaped bulks showed high trapped fields with almost concentric field distributions, reflecting homogeneous and boundaryless bulky crystal. In particular, a YBCO bulk with a 32 mm diameter trapped a high field more than 1 T at 77 K. Furthermore, rectangular and joined hexagonal REBCO bulks were successfully fabricated, showing designed field-trapping distributions reflecting their shapes through well-connected superconducting joints among bulks.