Continuous Solidification of YBa₂Cu₃O₇-x by Isothermal Undercooling

Abstract

Growth kinetics and microstructural development of single crystal YBa 2 Cu 3 O 7-x (Y123) superconductors, prepared by a method melt texturing undercooling under isothermal conditions were investigated. At small undercooling, ΔT=6K, the initial growth of yl23 crystal was terminated at a size of ∼8 mm x 8 mm in the semisolid phase before the entire sample was fully solidified through the peritectic reaction. At small undercooling, Δ = T 6K, the initial growth of yl23 crystal was terminated at a size of ~ 8 mm x 8 mm in the semisolid phase before the entire sample was fully solidified through the peritectic reaction. with incremental increase of AT, the growth of the crystal continued so that the whole sample (22 mm diameter and 8 mm thickness) solidified as a single crystal. with incremental increase of AT, the growth of the crystal continued so that the whole sample (22 mm diameter and 8 mm thickness) solidified as a single crystal. Termination of the crystal growth at a given undercooling temperature was attributed to the coarsening process of Y211 particles in the melt associated with their surface energy contributions. Termination of the crystal growth undercooling at a given temperature was attributed to the coarsening process of Y211 particles in the melt surface associated with their energy contributions. Isothermal growth of large size Y 123 single crystal requires a continuous supply of Y solute to the solidification interface which can be achieved by continuing dissolution of coarsening Y211 particles through further undercooling of the melt. Isothermal growth of large size Y 123 single crystal requires a continuous supply of Y solute to the solidification interface which can be achieved by continuing dissolution of coarsening Y211 particles through further undercooling of the melt.

Department(s)

Materials Science and Engineering

Keywords and Phrases

Crystal Growth from Melts; Cuprates; Experimental Study; High-Tc Superconductors; Inorganic Compounds; Isothermal Condition; Kinetics; Microstructure; Oxides; Solidification; Supercooling; Transition Element Compounds; Yttrium Barium Copper Mixed Oxides

International Standard Serial Number (ISSN)

0955-2219; 1873-619X

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2005 Elsevier Inc., All rights reserved.

Publication Date

01 Jan 2005

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