Processing and Sintering of Alumina-YAG Nanocomposites

Abstract:

The elaboration of 50 vol.% Al2O3/YAG (Y3Al5O12) nanocomposites was pursued by comparing two processing routes. In one case, a composite powder was firstly synthesized via reverse-strike co-precipitation and then submitted to an optimized thermal and extensive milling pre-treatment prior to sinter. In the second case, a pure-alumina precursor was prepared via reverse-strike precipitation and then doped with an yttrium salt solution; such doping procedure was performed on alumina samples submitted to several thermal and/or mechanical pre-treatments carried out to yield more or less relevant α-phase amounts. The optimization of the thermal/mechanical pre-treatment of the former powder led to a very homogeneous, dense and fine microstructure, made of α-alumina and YAG grains of about 300 nm in size. On the contrary, sintered bodies characterised by a larger mean grain size and a lower homogeneity in microstructure were obtained by using the second starting powder, even if, also in this case, a suitable control of the powder processing can allow a promising improvement of the microstructural features.

• Periodical: Advances in Science and Technology (Volume 45)
• Pages: 1696-1703
• DOI: https://doi.org/10.4028/www.scientific.net/AST.45.1696
• Online since: October 2006
• Authors: Paola Palmero, Laura Montanaro
• Keywords: Alumina-YAG Nanocomposites, Natural Sintering, Thermal Mechanical Treatment, Wet Chemical Synthesis

References

[1] K. Niihara, A. Nakahira, Particulate strengthened oxide ceamics-nanocomposites, Advanced Structural Inorganic Composites (Elsevier Science Publisher) Vol. 68 (1991) p.637.

[2] G.D. Zhan, J. Kuntz, J. Wan, J. Garay, A.K. Mkherjee: J. Amer. Cer. Soc. Vol. 86 (2002) p.200.

[3] L. Gao, H. Wang, H. Kawaoka, T. Sekino, K. Niihara: J. Europ. Cer. Soc., Vol. 22 (2002) p.22.

[4] W. Li, L. Gao: J. Europ. Cer. Soc. Vol. 20 (2000) p.2441.

[5] C. Legros, C. Carry, P. Bowen, H. Hofmann: J. Europ. Cer. Soc., Vol. 19 (1999) p. (1967).

[6] C. Scott Nordahl, G.L. Messing: J. Amer. Cer. Soc. Vol. 79 (1996) p.3149.

[7] P. Bowen, C. Carry: Powder Technology Vol. 128 (2002) p.248.

[8] J.G. Li, X. Sun: Acta Mater. Vol. 48 (2000) p.3103.

[9] P. Bowen. C. Carry, P. Luxembourg, H. Hofmann: Powder Technology Vol. 157 (2005) p.100.

[10] L. Radonjic, L. Nikolic: Ceramic International Vol. 25 (1999) p.567.

[11] J. -P. Ahn, J. -K. Park, H. -W. Lee: NanoStructured Mater. Vol. 11 (1999) p.133.

[12] P. Apte, H. Burke, H. Pickup: J. Mater. Res. Vol 7 (1992) p.706.

[13] H. Wang, L. Gao, K. Niihara: Mater. Sci. Eng., Vol. A288 (2000) p.1.

[14] P. Palmero, A. Simone, C. Esnouf, G. Fantozzi, L. Montanaro: J. Europ. Cer. Soc. Vol. 26 (2006) p.941.

[15] L. Montanaro, P. Palmero, A. Simone, C. Stella: Europen Patent n° EP05105757. 8, Torino, 28th June (2005).