Progress in Processing of Thin Wall HTc Bulk Superconducting Cryomagnets

• Published in: Journal of superconductivity and novel magnetism 2013-04, Vol.26 (4), p.959-963
• Main Authors: Noudem, J. G., Kenfaui, D., Chaud, X., Louradour, E., Zhou, D., Izumi, M.
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Cold working, work hardening; annealing, quenching, tempering, recovery, and recrystallization; textures; Condensed Matter Physics; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Cryomagnetic properties; Cuprates superconductors (high tc and insulating parent compounds); Domain effects, magnetization curves, and hysteresis; Engineering Sciences; Environmental Sciences; Exact sciences and technology; High-pressure and shock-wave effects in solids and liquids; Magnetic Materials; Magnetic properties and materials; Magnetism; Magnetization curves, magnetization reversal, hysteresis, barkhausen and related effects; Materials; Materials science; Mechanical and acoustical properties of condensed matter; Original Paper; Physics; Physics and Astronomy; Reactive fluid environment; Strongly Correlated Systems; Superconductivity; Thin walls; Treatment of materials and its effects on microstructure and properties; Y-based cuprates; YBCO superconductors
• ISSN: 1557-1939; 1557-1947
• DOI: 10.1007/s10948-012-1844-2

We report on our progress in the preparation of single domain of high temperature superconducting (HTS) bulk YBCO and GdBCO cryomagnets with multiple holes. Three mains steps have been explored and discussed in this study: Gd 2 BaCuO 5 (Gd211) and Y 2 BaCuO 5 (Y211) and thin wall preforms shaping by the extrusion technique. GdBa 2 Cu 3 O 3 (Gd123) YBa 2 Cu 3 O 3 (Y123) single domain obtained from Y211 using the Seed Infiltration Growth (SIG) process. Annealing under high oxygenation pressure in order to improve the superconducting properties. The thin wall samples with larger specific areas offer some advantages as better thermal exchange, shorter oxygen diffusion paths, possibility to reinforce the material to overcome the mechanically stresses during magnetization. The process and the microstructural features at various stages of processing, with particular emphasis on the characteristics of Gd211 and Y211 inclusions are discussed. Properties like the magnetic trapped field at different temperatures, the superconducting transition temperatures, and critical current densities of the resulting composites are presented and compared with their values in samples processed by other variants of the melt textured growth process.