Hostname: page-component-84b7d79bbc-fnpn6 Total loading time: 0 Render date: 2024-07-27T12:39:56.592Z Has data issue: false hasContentIssue false

Solidification Mechanism of YBa2Cu3Ox Superconductors

Published online by Cambridge University Press:  26 February 2011

Yuichi Nakamura
Affiliation:
Superconductivity Research Laboratory, ISTEC, 10–13 Shinonome 1-chome, Koto-ku, Tokyo, 135, Japan
Teruo Izumi
Affiliation:
Superconductivity Research Laboratory, ISTEC, 10–13 Shinonome 1-chome, Koto-ku, Tokyo, 135, Japan
Yuh Shiohara
Affiliation:
Superconductivity Research Laboratory, ISTEC, 10–13 Shinonome 1-chome, Koto-ku, Tokyo, 135, Japan
Shoji Tanaka
Affiliation:
Superconductivity Research Laboratory, ISTEC, 10–13 Shinonome 1-chome, Koto-ku, Tokyo, 135, Japan
Get access

Abstract

Directional solidification of the zone melting method was performed in order to clarify the growth mechanism on YBa2Cu3Ox (123) superconductors from the partial molten state. The effect of a platinum addition for crystal growth was also investigated. Results indicate that a higher G/R ratio was preferable for the continuous growth of 123 crystals, and lead to the idea that the necessary solute for the peritectic reaction is provided from dispersed Y2BaCuO5 (211) particles in liquid to 123 interface through the liquid. Based on this idea, we developed a solidification model which is in good agreement with the experimental results. In the case of a platinum addition, the coarsening rate of 211 particles decreased, and the cell spacing of 123 crystals also decreased. It is tentatively suggested that the platinum addition decreases the products of the diffusivity in liquid and the Gibbs-Thomson coefficients, which include the surface energy between 211 or 123 phase and liquid,(DLΓ211 and DLΓ123).

Type
Research Article
Copyright
Copyright © Materials Research Society 1992

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

[1] Ogawa, N., Hirabayashi, I. and Tanaka, S., Physica C 177, 101 (1991).Google Scholar
[2] Izumi, T., Nakamura, Y., Sung, T. H. and Shiohara, Y., J. Mater. Res.,in press.Google Scholar
[3] Izumi, T. and Shiohara, Y., J. Mater. Res. 7, 16 (1992).Google Scholar
[4] Flemings, M. C., in Solidification Precessing (McGraw-Hill, New York 1974), p. 58.Google Scholar
[5] Rutter, J. W. and Chalmers, B., Can. J. Phys. 21, 15 (1953)Google Scholar
[6] Izumi, T., Nakamura, Y. and Shiohara, Y., J. Mater. Res.,in pressGoogle Scholar
[7] Kurz, W. and Fisher, D. J., in Fundamentals of Solidification, 3rd ed. (Trans Tech Publications, Switzerland, 1989), p. 80.Google Scholar