Single-domain Yba₂Cu₃O_y thick films and fabrics prepared by an infiltration and growth process

Abstract

An infiltration and growth process has been developed to produce single-domain YBa 2 Cu 3 O y (123) as thick films on various substrates or as self-supporting fabrics. Commercially available Y 2 O 3 cloths of square woven or satin woven structure were infiltrated with liquid phases from a suitable source containing barium cuprates and copper oxides and subsequently converted into Y 2 BaCuO 5 (211) and -123 phases by a series of distinct peritectic reactions. Depending on the final form of 123, the Y 2 O 3 cloth was either clamped firmly at corners to produce a self-supporting 123 fabric or placed on a suitable substrate to result in a thick film coating of 123. The source material for the liquid phase being in the form of solid blocks was placed at corners of the cloth in the case of free-standing 123 fabrics. In case of the thick film configuration the liquid phase powder was spread on the surface of the Y 2 O 3 cloth. A small c-axis-oriented MgO or Nd(123) seed was used to generate an oriented 123 domain in the infiltrated fabric. The solidification process was optimized to transform the entire Y 2 O 3 fabric into a single-domain 123. The microstructure of the single domain was optimized in terms of 211 size and content for high J c . A detailed description of the process, the growth mechanism, the resulting microstructures was given, and basic superconducting properties of the new form of 123 are briefly discussed.

Natural strategies for creating non-equilibrium morphology with self-repairing capability towards rapid growth of excellent YBa2Cu3O7−δ crystals

“…Apart from multiple-seeding methods, one more conventional strategy for large-scale REBCO crystals is the utilization of a large-sized seed (Li et al, 2015;Wu et al, 2009), by which a sizable c-GS could be directly induced (Guo et al, 2015;Li et al, 2015). However, a large seed means a large surface coverage, which inhibits the release of oxygen derived from peritectic melting (Sudhakar Reddy et al, 2001). The residual bubbles largely accumulate as pores in the crystallized sample and are certainly detrimental to the superconducting properties (Li et al, 2015).…”

Superconducting foams

“…The method used to convert these 211 foams into single domain 123 foams is similar to the infiltration process used for the fabrication of superconducting fabrics [11] and nearnet shaped bulk components or materials [12]. The process involves the infiltration of liquid phases into the body of the 211 foam from a liquid phase source.…”