Hostname: page-component-848d4c4894-pjpqr Total loading time: 0 Render date: 2024-06-16T04:24:41.465Z Has data issue: false hasContentIssue false

Electrical properties of silica-alumina ceramics in nitrogen atmosphere

Published online by Cambridge University Press:  31 January 2011

Yoshihiro Hirata
Affiliation:
Department of Applied Chemistry and Chemical Engineering, Faculty of Engineering, Kagoshima University, 1-21-40 Korimoto, Kagoshima 890, Japan
Mitsunori Kawabata
Affiliation:
Department of Applied Chemistry and Chemical Engineering, Faculty of Engineering, Kagoshima University, 1-21-40 Korimoto, Kagoshima 890, Japan
Yoshimi Ishihara
Affiliation:
Department of Applied Chemistry and Chemical Engineering, Faculty of Engineering, Kagoshima University, 1-21-40 Korimoto, Kagoshima 890, Japan
Get access

Abstract

The SiO2–Al2O3 powders with compositions of 46.5 to 76.6 wt. % Al2O3, synthesized by the hydrolysis of metal alkoxides, were sintered at 1700 °C for 3 h in a reduced pressure of 40 Pa. After sintering, the samples were annealed at 1300 °C for 10 h in air. The densities of sintered samples were higher than 97.0% T.D. The electrical conductivities of the SiO2–Al2O3 ceramics in N2 atmosphere (>99.99%) were measured in the temperature range of 500° to 800 °C by using ac bridge circuit at 120 Hz to 1 MHz and dc circuit at 1 V. The electrical conductivities at 800 °C were 3.4 × 10−7 to 4.3 × 10−6 S cm−1, and decreased with increasing Al2O3 content. The SiO2–Al2O3 ceramics were mixed conductors of oxygen ions and electrons in nitrogen atmosphere. The activation energies of ionic and electronic conductivities were 102 to 143 kJ/mole and 102 to 123 kJ/mole, respectively.

Type
Articles
Copyright
Copyright © Materials Research Society 1993

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

1Aksay, I. A. and Pask, J.A.J. Am. Ceram. Soc. 58, 507512 (1975).CrossRefGoogle Scholar
2Kanzaki, S.Kurihara, T.Iwai, S.Ohashi, M. and Tabata, H.J. Ceram. Soc. Jpn. 95, 12131218 (1987).Google Scholar
3Ushifusa, N.Sakamoto, K.Nagayama, K. and Ogihara, S.J. Ceram. Soc. Jpn. 98, 377383 (1990).CrossRefGoogle Scholar
4Hashimoto, K. and Niwa, K.J. Ceram. Soc. Jpn. 95, 10371039 (1987).Google Scholar
5Hirata, Y.Sakeda, K.Matsushita, Y.Shimada, K. and Ishihara, Y.J. Am. Ceram. Soc. 72, 9951002 (1989).CrossRefGoogle Scholar
6Hirata, Y. and Matsuda, M.J. Ceram. Soc. Jpn. 101 (1993, in press).Google Scholar
7Fischer, V. W. A. and Janke, D.Arch. Eisenhiittenwesen 40, 707716 (1969).Google Scholar
8Aksay, I. A. Ph.D. Thesis University of California, Berkeley, CA, 1973.Google Scholar
9Oishi, Y. and Ando, K. in Advances in Ceramics Vol. 10, Structure and Properties of MgO and AI2O3 Ceramics, edited by Kingery, W. D. (The American Ceramic Society Inc., Westerville, OH, 1984), pp. 379393.Google Scholar
10Paladino, A.E. and Kingery, W.D.J. Chem. Phys. 37, 957962 (1962).CrossRefGoogle Scholar
11Kingery, W. D.Bowen, H. K. and Uhlmann, D. R. in Introduction to Ceramics, 2nd ed. (John Wiley & Sons, New York, 1975), p. 240.Google Scholar
12Cameron, W.E.Am. Mineral. 62, 747-755 (1977).Google Scholar
13Dell, R. M. and Hooper, A. in Solid Electrolytes, General Principles, Characterization, Materials, Applications, edited by Hagenmuller, P. and Gool, W. V. (Academic Press, New York, 1978), pp. 291312.Google Scholar