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Preparation and Optical Properties of Polycrystalline Aluminum Germanate

Published online by Cambridge University Press:  15 February 2011

S. Prochazka  and
G. A. Slack
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Extract

Aluminum germanate, the germanium analog of mullite, 3 AlO2O3 . 2 GeO2, was first prepared by Gelsdorf, Muller-Hesse and Schweite (Ref. 1), who demonstrated that both partial and complete substitution of SiO2 by GeO2 in mullite was possible. They also determined the lattice constants of the solid solutions. The following studies reported some physical properties of aluminum germanate such as density (Ref. 2) optical constants (Ref. 2) crystal structure (Ref. 3) and I. R. absorption (Ref. 4). Phase equilibria in the system AlO2O3−GeO2 were investigated by Miller et al. (Ref. 5) and Perez-y-Jorba (Ref. 6). The ratter author found several compounds of which germanium mullite was the most stable and showed a relatively wide compositional range. Miller et al. observed only 3 Al2O3 . 2 GeO2 with no evidence of solid solutions. The compound was reported to melt incongruently at 1530° C. Recently Yamaguchi et al. (Ref. 7) prepared aluminum germanates of a wide range of stoichiometry from alkyl oxides and found, in addition to germanium mullite, the compound Al2O3−2GeO2 which was stable between 1190° and 1310° C. The authors also report infrared absorption spectra.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 32: Symposium B – Better Ceramics Through Chemistry I , 1984 , 245
Copyright
Copyright © Materials Research Society 1984

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References

REFERENCES

1. Gelsdorf, G., Muller-Hesse, H., Schwiete, H.E., “Einlagerungsversuche an synthetischem Mullit und Substitutionsversuche mit Gallium und Germaniumoxyd”, Arch. F. Eisenhuttenwesen, 29, 513–520 (1958).Google Scholar
2. Toropov, N.A., Ardreev, I.F., Orlov, V.A., Schmitt-Fogelevich, S.P., “Synthesis of Germanium Mullite and Study of its Properties”, Zhur. Prikl. Khimii, 43, 2143–47 (1970).Google Scholar
3. Durovic, S., Fejdi, P., “Synthesis and Crystal Structure of Germanium Mullite”, Silikaty 20, 97 (1976).Google Scholar
4. Muller-Hesse, H., “Infrarotspektrographische Untersuchungen im System A12O3-SiO2”, Fortschritte Mineralog, 38, 173 (1960).Google Scholar
5. Miller, J.L., McCormick, G.R., Ampian, S.G., “Phase Equilibria in the System GeO2-A12O3”, Jour. Am. Cer. Soc., 50, 268 (1967).Google Scholar
6. Perez y Jorba, M., “Les systemes GeO2-A12O3 et GeO2-Fe2O3”, Silicates Ind., 33, 11–17 (1968).Google Scholar
7. Yamaguchi, O., Kanazawa, T., Yokoiga, M., Shimizu, K., “Formation of Akoxy-Derived 3A12O3.2GeO2” Ceramics International 9 (1) 18–21 (1983).Google Scholar
8. Mazdiyasni, K.S., Brown, L.M., “Synthesis and Mechanical Properties of Stoichiometric Aluminum Silicate (Mullite), Jour. Am. Ceram. Soc. 55, 548–552 (1972).Google Scholar
9. Hoch, M., Nair, K.M., “Densification Characteristics of Ultrafine Powders”, Proc. 3rd CIMTEC Int. Meeting on Modern Ceramic Technologies, May 1976.Google Scholar
10. Prochazka, S., “Sintering and Properties of Dense Aluminum Germanate” in Ceramic Powders, Vincenzini, P. ed., 1983, Elsevier Amsterdam.Google Scholar
11. Prochazka, S., Huseby, I.C., Goehner, R.P., “Thermal Expansion Anisotropy and Microcracking in Mullite and Germanium Mullite”, G.E. CRD Report 82CRD288, November 1982. (Available on request)Google Scholar