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Hardening in AlN Induced by Point Defects

Published online by Cambridge University Press:  28 February 2011

H. Suematsu ,
T. E. Mitchell ,
T. Iseki  and
T. Yano
H. Suematsu
Affiliation:
Center for Materials Science, Los Alamos National Laboratory, Los Alamos, NM 87545, U. S. A.
T. E. Mitchell
Affiliation:
Center for Materials Science, Los Alamos National Laboratory, Los Alamos, NM 87545, U. S. A.
T. Iseki
Affiliation:
Department of Inorganic Materials, Tokyo Institute of Technology, O-okayama, Meguroku, Tokyo 152, Japan
T. Yano
Affiliation:
Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, O-okayama, Meguroku, Tokyo 152, Japan.
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Abstract

Pressureless-sintered AlN was neutron irradiated and the hardness change was examined by Vickers indentation. The hardness was increased by irradiation. When the samples were annealed at high temperature, the hardness gradually decreased. Length was also found to increase and to change in the same way as the hardness. A considerable density of dislocation loops still remained, even after the hardness completely recovered to the value of the unirradiated sample. Thus, it is concluded that the hardening in AlN is caused by isolated point defects and small clusters of point defects, rather than by dislocation loops.

Hardness was found to increase in proportion to the length change. If the length change is assumed to be proportional to the point defect density, then the curve could be fitted qualitatively to that predicted by models of solution hardening in metals. Furthermore, the curves for three samples irradiated at different temperatures and fluences are identical. There should be different kinds of defect clusters in samples irradiated at different conditions, e.g, the fraction of single point defects is the highest in the sample irradiated at the lowest temperature. Thus, hardening is insensitive to the kind of defects remaining in the sample and is influenced only by those which contribute to length change.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 235: Symposium A – Phase Formation and Modification by Beam-Solid Interactions , 1991 , 445
Copyright
Copyright © Materials Research Society 1992

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References

REFERENCES

1. Wullaert, R. A., Burian, R. J., Melehan, J. B., Kangilaski, M. and Gates, J. E., in Effects of Radiation on Ceramic Materials. Editor Kircher, J. F. and Bowman, R. E. (Reinhold Publishing Co., New York, U. S. A., 1964), p. 277.Google Scholar
2. Brundnyi, V. N.. and Tolebaev, B. T., Sov. Atom. Ener., 59, 787 (1986).Google Scholar
3. Hobbs, L. W., Private comunication.Google Scholar
4. Zinkle, S. J., J. Am. Ceram. Soc, 72, 1343 (1989).Google Scholar
5. Suematsu, H., Iseki, T., Yano, T., Saito, Y., Suzuki, T. and Mori, T., Submitted to J. Am. Ceram. Soc.Google Scholar
6. Iseki, T., Tezuka, M., Kim, C. S., Suzuki, T., Suematsu, H. and Yano, T., submitted to British Ceram. Trans.Google Scholar
7. Yano, T., Tezuka, M., Miyazaki, H. and Iseki, T., Submitted to J. Nucl. Mater.,Google Scholar
8. Fleischer, R. L., J. Appl. Phys., 33, 3504 (1962).Google Scholar
9. Mitchell, T. E. and Heuer, A. H., Mater. Sci. Eng., 28, 81 (1977).CrossRefGoogle Scholar
10. Suzuki, T., Maruyama, T., Iseki, T., Mori, T. and Ito, M., J. Nucl. Mater., 149, 334 (1987).CrossRefGoogle Scholar
11. Suzuki, T., Yano, T., Maruyama, T., Iseki, T. and Mori, T., J. Nucl. Mater., 165, 247 (1989).CrossRefGoogle Scholar
12. Palentine, J. E., J. Nucl. Mater., 61, 243 (1976).Google Scholar
13. Yano, T. and Iseki, T., J. Nucl. Mater., 179–181, 387 (1990).Google Scholar