Tuning the top-seeded melt growth of REBCO single-domain superconducting bulks by a pyramid-like buffer stack

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

“…The presence of silver improves the microstructure of the final bulk material by filling any oxygen‐induced defects (primarily pores and cracks generated during melt processing), thereby enhancing significantly its mechanical properties. Moreover, because untreated defects act as stress concentration points, the addition of silver also helps to limit crack propagation during mechanical stress induced by the trapped field 27–30 …”

“…Moreover, because untreated defects act as stress concentration points, the addition of silver also helps to limit crack propagation during mechanical stress induced by the trapped field. [27][28][29][30] 10 wt.% of Ag 2 O was added the precursor powder (i.e., a total of 110 %) to obtain a sufficient temperature difference between the seed plate material and the precursor bulk composition, as is common in the preparation of certain (RE)BCO systems, including EuBCO. The silver fills any defects in the bulk sample during the single grain growth process and improves the microstructure, and therefore the mechanical properties of the fully processed sample.…”

Transport Current Measurement of $I_{c}(T, B,\theta)$ and $n(T, B,\theta)$ for a Bulk REBCO Superconductor

“…Commercially available 35 mm diameter single-grain GdBCO-Ag bulk (CAN SUPERCONDUCTORS) was prepared by standard top-seeded melt growth technique from precursor powder with nominal composition Gd 1.8 Ba 2.45 Cu 3.4 O x + 10 w.t.% Ag 2 O [45]. An NdBCO thin film on MgO substrate was used as a seed, with a small (8mm diameter) buffer pellet (from the same precursor powder).…”

Novel chemical recycling process of REBCO materials showcased on TSMG-processed waste

“…20 Secondary grains can grow in the bulk, significantly deteriorating its properties, which is why such bulks are most often discarded. [21][22][23] Another type of defect is large cracks in the volume of the bulk. 24,25 This is a problem mainly for bulks that are larger in diameter since during growth, the bulks are under higher stress due to high shrinkage during heat treatment.…”