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Anisotropic thermal expansion in yttrium silicate

Published online by Cambridge University Press:  31 January 2011

Koichiro Fukuda
Affiliation:
Department of Materials Science and Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan
Hiroyuki Matsubara
Affiliation:
Department of Materials Science and Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan
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Abstract

In this study, crystals of Y2SiO5 were examined by high-temperature powder x-ray diffractometry to determine the changes in unit-cell dimensions with temperatures up to 1273 K for the X1 phase (the low-temperature phase, space group P121/c1) and 1473 K for the X2 phase (the high-temperature phase, space group I12/a1). The lattice deformations of both phases induced by thermal expansion were investigated by matrix algebra analysis to determine the directions and magnitudes of the principal distortions (λi, i = 1, 2, and 3). For the X1 phase, λ1 and λ2 invariably showed a positive thermal expansion. On the other hand, λ3 showed a negative thermal expansion below 1173 K; the maximum contraction of 0.10(4)% occurred at 685 K. The λ2 axis invariably coincides with the crystallographic b axis. The directions of λ1 and λ3, defined by the acute angle λ3 ^ c changed between 53(3)° (T = 394 K) and 45(1)° (T = 788 K). For the X2 phase, all of the principal distortions steadily increased with increasing temperature. The angle λ3 ^ c steadily decreased from 71(2)° to 62.1(1)° with increasing temperature. The mean linear thermal expansion coefficients were, when compared at the same temperatures, necessarily higher for the X1 phase than for the X2 phase. The lattice change of X1–RE2SiO5 (RE = Y and Yb–La), which was induced by the substitution of rare-earth (RE) ions, showed a striking resemblance with the lattice deformation of X1-Y2SiO5, which was caused by the thermal expansion. Because the lattice change of the former must be caused by the isotropic expansion of the RE sites, the anisotropic thermal expansion of the latter would be essentially attributable to the isotropic thermal expansion of the YO9 and YO7 polyhedron.

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Articles
Copyright
Copyright © Materials Research Society 2003

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References

REFERENCES

1.Ogura, Y., Kondo, M., and Morimoto, T., Proc. 10th Int. Conf. Compos. Mater., 4, 767 (1995).Google Scholar
2.Ogura, Y., Kondo, M., Morimoto, T., Takeda, Y., and Notomi, A., Nippon Kinzoku Gakkaishi 63, 1295 (1999).Google Scholar
3.Aparicio, M. and Duran, A., J. Am. Ceram. Soc. 83, 1351 (2000).CrossRefGoogle Scholar
4.Wang, J., Tian, S., Li, G., Liao, F., and Jing, X., Mater. Res. Bull. 36, 1855 (2001).Google Scholar
5.Leonyuk, N.I., Belokoneva, E.L., Bocelli, G., Righi, L., Shvanskii, E.V., Henrykhson, R.V., Kulman, N.V., and Kozhbakhteeva, D.E., Cryst. Res. Technol. 34, 1175 (1999).3.0.CO;2-2>CrossRefGoogle Scholar
6.Maksimov, B.A., Kharitonov, Yu.A., Ilyukhin, V.V., and Belov, N.V., Dokl. Akad. Nauk SSSR 183, 1072 (1968).Google Scholar
7.Maksimov, B.A., Ilyukhin, V.V., Kharitonov, Yu.A., and Belov, N.V., Kristallografiya 15, 926 (1970).Google Scholar
8.Ito, J. and Johnson, H., Am. Mineral. 53, 1940 (1968).Google Scholar
9.Nowok, J.W., Kay, J.P., and Kulas, R.J., J. Mater. Res. 16, 2251 (2001).CrossRefGoogle Scholar
10.Felsche, J., in The Crystal Chemistry of the Rare-Earth Silicates: Structure and Bonding, edited by Dunitz, J.D., Hemmerich, P., Ibers, J.A., Jorgensen, C.K., Neilands, J.B., SirNyholm, R.S., Reinen, D., and Williams, R.J.P. (Springer-Verlag, Berlin, Germany, 1973), Vol. 13, pp. 104–112.Google Scholar
11.Zhdanov, G.S., Crystal Physics, translated and edited by Brown, A.F. (Oliver & Boyd Press, Edinburgh, U.K., 1965), pp. 411–420.Google Scholar
12.Nye, J.F., Physical Properties of Crystals (The Clarendon Press, Oxford, U.K., 1957), pp. 63–109.Google Scholar
13.O'Bryan, H.M., Gallagher, P.K., and Berkstresser, G.W., J. Am. Ceram. Soc. 71, C42 (1988).CrossRefGoogle Scholar
14.Toraya, H., J. Appl. Crystallogr. 19, 440 (1986).CrossRefGoogle Scholar
15.Simmons, R.O., J. Appl. Phys. 41, 2235 (1970).Google Scholar
16.Christian, J.W., The Theory of Transformations in Metals and Alloys (Pergamon Press, Oxford, U.K., 1975), pp. 40–48.Google Scholar
17.Fukuda, K., Maki, I., and Ito, S., J. Am. Ceram. Soc. 80, 1595 (1997).CrossRefGoogle Scholar
18.Fukuda, K., J. Ceram. Soc. Jpn. 109, 830 (2001).Google Scholar
19.Fukuda, K. and Yamauchi, K., J. Mat. Res. 17, 1050 (2002).CrossRefGoogle Scholar
20.Shannon, R.D., Acta Crystallogr. A32, 751 (1976).CrossRefGoogle Scholar