Crystal growth of melt-textured Nd-123 under 1% oxygen partial pressure atmosphere

• Published in: IEEE transactions on applied superconductivity Vol. 11; no. 1; pp. 3442 - 3445
• Main Authors: Kambara, M., HariBabu, N., Shi, Y., Cardwell, D.A.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: New York, NY IEEE 01.03.2001; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Atmosphere; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Critical current density; Cross-disciplinary physics: materials science; rheology; Crystal growth; Crystal microstructure; Crystals; Cuprates superconductors (high tc and insulating parent compounds); Exact sciences and technology; Growth from melts; zone melting and refining; Isothermal processes; Materials science; Methods of crystal growth; physics of crystal growth; Neodymium; Other cuprates; Oxygen; Partial pressure; Physics; Solidification; Solids; Steady-state; Superconductivity; Supercooling; Telephony; Temperature; Undercooling
• ISSN: 1051-8223; 1558-2515
• DOI: 10.1109/77.919803

Crystal growth of melt-textured Nd-123 pseudo-crystals was investigated via an isothermal solidification with top-seeding technique under a 1%O/sub 2/ in N/sub 2/ atmosphere. Nonsteady state solidification was observed at low undercooling, in contrast to an almost linear growth at higher undercooling. Similar to processing in air, the substitution of Nd/Ba was found to decrease from the seed position to the edge of the crystal. In addition, the volume fraction of Nd-422 particles decreased in the solid as solidification proceeded. As a result of these microstructural inhomogeneities, the critical temperature and the critical current density varied within the crystal even for samples processed isothermally, despite the narrow solid solution range of the Nd-123 phase under a reduced pO/sub 2/ atmosphere.