Hostname: page-component-77c89778f8-swr86 Total loading time: 0 Render date: 2024-07-17T03:59:22.806Z Has data issue: false hasContentIssue false
  • English
  • Français

Phase Equilibria Studies Near the Superconducting YBa2Cu3Ox Composition by a Solid-State Ionic Technique

Published online by Cambridge University Press:  28 February 2011

Byung Tae Ahn ,
Turgut M. Gür ,
Robert A. Huggins ,
Robert Beyers  and
Edward M. Engler
Byung Tae Ahn
Affiliation:
Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305–2205
Turgut M. Gür
Affiliation:
Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305–2205
Robert A. Huggins
Affiliation:
Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305–2205
Robert Beyers
Affiliation:
IBM Almaden Research Center, 650 Harry Road San Jose, CA 95120–6099
Edward M. Engler
Affiliation:
IBM Almaden Research Center, 650 Harry Road San Jose, CA 95120–6099
Get access

Abstract

This paper reports the findings of a phase-equilibrium study of the Y-Ba-Cu-O quaternary system in which the oxygen activity was monitored and controlled by a solid-state ionic technique. A stabilized zirconia electrolyte was used to titrate oxygen in or out of the sample and to monitor the oxygen activity inside a sealed sample chamber.

Compositions at or near YBa2Cu3Ox were studied at elevated temperatures in a wide range of oxygen pressures. All compositions indicated the presence of an invariant polyphase reaction- e.g., at 1 × 10-3 atm of oxygen pressure at 850 °C-- below which the superconducting phase becomes thermodynamically unstable and undergoes a decomposition reaction. Complementary x-ray diffraction analysis of samples prepared under well-defined oxygen pressures identified the phases present and, along with the oxygen coulometric titration data, allowed the construction of a portion of the relevant quarternary phase diagram.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 99: Symposium AA – High-Temperature Superconductors , 1987 , 171
Copyright
Copyright © Materials Research Society 1988

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] Cava, R.J., van Dover, R.B., Batlogg, B., Rietman, E.A., Phys. Rev. Lett. 58, 408 (1987)Google Scholar
[2] Tarascon, J.M., Greene, L.H., McKinnon, W.R., Hull, G.W., and Geballe, T.K., Science, 235, 1373 (1987)Google Scholar
[3] Giir, T.M., Raistrick, I.D., and Huggins, R.A., Mat. Sci. Engr. 46, 53 (1980)Google Scholar
[4] Giir, T.M., Raistrick, I.D., and Huggins, R.A., J. Electrochem. Soc, 127, 2620 (1980)Google Scholar
[5] Engler, E.M., Lee, V.Y., Nazzal, A.I., Beyers, R.B., Lim, G., Grant, P.M., Parkin, S.S.P., Ramirez, M.L., Vazquez, J.E. and Savoy, R.J., J. Amer. Chem. Soc. 109, 2848 (1987)Google Scholar
[6] Barin, I. and Knacke, O., Thermochemical Properties of Inorganic Substances. (Springer-Verlag, 1973)Google Scholar