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Decomposition of the ZrO2 electrolyte in contact with Ni: Structure and chemical composition of the Ni–electrolyte interface

Published online by Cambridge University Press:  31 January 2011

Thomas Wagner
Affiliation:
Max-Planck-Institut für Metallforschung, D-70174 Stuttgart, Germany
Gerd Duscher
Affiliation:
Max-Planck-Institut für Metallforschung, D-70174 Stuttgart, Germany
R. Kirchheim
Affiliation:
Universität Göttingen, Institut Für Materialphysile, D-37073 Göttingen, Germany
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Abstract

The Ni/(ZrO2 + 9.5 mol% Y2O3) interface was used as a model system to investigate decomposition reactions of a yttria-stabilized ZrO2 electrolyte in contact with a metal at elevated temperature. In the present study, the sample was a diffusion-bonded symmetrical galvanic cell Ni‌ZrO2 + 9.5 mol% Y2O3‌Ni. Various electron microscopy techniques were used to study the morphology and structure of the reaction products at the Ni–ZrO2 electrolyte phase boundary after current flow. Below a critical oxygen partial pressure of approximately 10−27 atm, an intermetallic reaction layer formed at the Ni–electrolyte interface. Between the intermetallic layer and electrolyte a thin Y2O3 layer was present, which acted as a diffusion barrier for Zr and Ni, slowing down the overall chemical reaction. At several locations at the interface the Y2O3 layer broke up, leading to a morphological instability of the interface between electrolyte and Ni5Zr, allowing further reaction. The thickness of the total reaction layer varied widely as a consequence of such an instability.

Type
Articles
Copyright
Copyright © Materials Research Society 1999

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References

REFERENCES

1.Bloor, D., Brook, R.J., Flemings, M.C., and Mahajan, S., The Encyclopedia of Advanced Materials (Cambridge University Press, Cambridge, 1994).Google Scholar
2.Wagner, T., Kirchheim, R., and Rühle, M., Acta Metall. Mater. 43, 1053 (1995).Google Scholar
3.Wagner, T., Kirchheim, R., and Rühle, M., Acta. Metall. Mater. 40, S85 (1992).CrossRefGoogle Scholar
4.Strecker, A., Salzberger, U., and Mayer, J., Prakt. Metallogr. 30, 481 (1993).Google Scholar
5.Rickert, H., Electrochemistry of Solids (Springer, Berlin, 1982).Google Scholar
6.Ramanarayanan, T. and Worrell, W.L., Met. Trans. 5, 1773 (1974).CrossRefGoogle Scholar
7.Fischer, W.A. and Janke, D., Metallurgische Elektrochemie (Springer, Berlin, 1975).CrossRefGoogle Scholar
8.Swanson, and Fuyat, , NBS Circular 539 3, 28 (1954).Google Scholar
9.Scott, H.G., J. Mat. Sci. 10, 1527 (1975).Google Scholar
10.Rao, C.N. and Rao, G.V.S, Transition Metal Oxides (National Bureau of Standards, Washington, 1974).CrossRefGoogle Scholar