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A comparison of mm-wave Sintering and Fast Conventional Sintering of Nanocrystalline Al2O3

Published online by Cambridge University Press:  10 February 2011

G. Link
Affiliation:
Forschungszentrunm Karlsruhe; ITP
V. Ivanov
Affiliation:
Institute of Electrophysics, RAS, Komsomolskay 34, Ekaterinburg 620219, Russia
S. Paranin
Affiliation:
Institute of Electrophysics, RAS, Komsomolskay 34, Ekaterinburg 620219, Russia
V. Khrustov
Affiliation:
Institute of Electrophysics, RAS, Komsomolskay 34, Ekaterinburg 620219, Russia
R. Böhme
Affiliation:
INR; P.O.Box 3640, 76021 Karalsruhe, Germany
G. Müller
Affiliation:
Institut für Plasmoforschung, Pfaffenwaldring 31, 70569 Stuttgart, Germany
G. Schumacher
Affiliation:
INR; P.O.Box 3640, 76021 Karalsruhe, Germany
M. Thumm
Affiliation:
Forschungszentrunm Karlsruhe; ITP University Karalsruhe, IHE, Kaiserstr. 12, 76128 Karlsruhe, Germany
A. Weisenburger
Affiliation:
INR; P.O.Box 3640, 76021 Karalsruhe, Germany
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Abstract

The phase transformation and densification behavior under high power millimeter-wave (mm-wave) radiation of a 30 GHz gyrotron and during fast conventional sintering of nanocrystalline γ-A12O3 powder have been investigated and compared. The powder used for compacts was synthesized from aluminum metal by application of the exploding wire technique in an oxidizing atmosphere. The particle size distribution of this powder has a maximum at about 20 nm. Magnetic pulse technique was applied for the compression of samples up to 80% of the theoretical density (TD). Both mm-wave sintering and fast firing in a conventional electrical resistance furnace enable the densification and a complete phase transformation into α-A12O3 already at a temperature of approximately 1150 %C. The average grain size of the sintered ceramic is in the range of 50 to 100 nm. With mm-waves densification starts at about 50 °C lower temperatures compared to conventional techniques and higher final densities were obtained already at 150°C lower temperatures.

Type
Research Article
Copyright
Copyright © Materials Research Society 1996

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References

1. Karch, J., Birringer, R., Gleiter, H., Nature, 330 (10), 556 (1987).Google Scholar
2. Hahn, H., NanoStructured Materials, 2, 251 (1993).Google Scholar
3. Eastman, J.A. et al.; Mat. Res. Soc. Symp. Proc., 189, 273 (1991).Google Scholar
4. Jinsong, Zh. et al.; Mat. Res. Soc. Symp. Proc., 347, 591 (1994).Google Scholar
5. Freim, J. et al., NanoStructured Materials, 4 (4), 371 (1994).Google Scholar
6. Bykov, Yu.V.. et al., MIOP ‘95, Conf. Proc. of 8th Exhibition and Conference on High Frequency and Engineering, Sindelfingen, Germany, 321 (May 30.-June 1. 1995).Google Scholar
7. Beketov, I.V. et al., Conf. Proc. 4th Euro Ceramics, Riccione; 1, 77 (October 2.-6. 1995).Google Scholar
8. Ivanov, V.V. et al., Conf. Proc. 4th Euro Ceramics, Riccione; 2., 169 (October 2.-6. 1995).Google Scholar
9. Adamenko, B.G., Pashkov, P.O., Poroshcovaya Metallurgia, 190, 93 (1978) (in Russian).Google Scholar