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Role of Deformable Fine Spinel Particles in High-Strain-Rate Superplastic Flow of Tetragonal ZrO2

Published online by Cambridge University Press:  15 March 2011

Koji Morita
Affiliation:
National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
Keijiro Hiraga
Affiliation:
National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
Byung-Nam Kim
Affiliation:
National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
Yoshio Sakka
Affiliation:
National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan
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Abstract

The role of MgAl2O4 spinel particle dispersion in high-strain-rate superplasticity (HSRS) of tetragonal ZrO2 was examined by characterizing microstructural changes during deformation. The dispersed spinel particles elongate with strain along tensile direction and the elongation tends to be pronounced with increasing strain rate. In the elongated spinel particles, intragranular dislocations lying along the elongated direction were observed, suggesting that the elongation relates to the dislocation motion. The flow behavior characterized by a stress exponent of ≈ 2.0 suggests that grain boundary sliding (GBS) is the predominant flow mechanism. The dislocation-induced plasticity in the spinel particles may assist the relaxation of stress concentrations exerted by GBS, leading to HSRS in tetragonal ZrO2.

Type
Research Article
Copyright
Copyright © Materials Research Society 2004

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References

1. Kim, B.-N., Hiraga, K., Morita, K. and Sakka, Y., Nature 413, 288 (2001).Google Scholar
2. Kim, B.-N., Hiraga, K., Morita, K., Sakka, Y. and Yamada, T., Scripta Mater. 47, 775 (2002).Google Scholar
3. Morita, K., Hiraga, K. and Sakka, Y., J. Am. Ceram. Soc. 85, 1900 (2002).Google Scholar
4. Morita, K., Kim, B. N., Hiraga, K. and Sakka, Y., Mat. Sci. Forum 447–448, 329 (2004).Google Scholar
5. Morita, K., Hiraga, K., Kim, B. N. and Sakka, Y., Mater. Trans., in press (2004).Google Scholar
6. Nieh, T. G., McNally, C. M. and Wadsworth, J., Scripta Mater. 24, 763 (1989).Google Scholar
7. Schissler, D.J., Chokshi, A. H., Nieh, T.G. and Wadswort, J., Acta Mater. 39, 3227 (1991)Google Scholar
8. Kondo, T., Takigawa, Y., Sakuma, T. Mat. Trans. JIM 1108 (1998).Google Scholar
9. Wurst, J.C. and Nelson, J.A., J. Am. Ceram. Soc. 55, 109 (1972).Google Scholar
10. Nieh, T.G., Wadsworth, J. and Sherby, O.D., “Superplasticity in Metals and Ceramic,” (Cambridge University Press, 1997) pp. 91119.Google Scholar
11. Montia, K., Huraga, K., Kim, B.K. and Sakka, Y., J. Am. Ceram. Soc., to be submitted.Google Scholar
12. Jiménez-Melendo, M., Dominguez-Rodríguez, A., and Bravo-León, A. J.Am. Ceram.Soc. 81 2761 (1998).Google Scholar
13. Mitchell, T.E., J. Am. Ceram Soc. 82, 3305 (1999).Google Scholar