Combustion synthesis of aluminium titanate

• Published in: Journal of the European Ceramic Society 1998, Vol.18 (7), p.771-781
• Main Authors: Segadães, Ana M., Morelli, Márcio R., Kiminami, Ruth G.A.
• Format: Article
• Language: English
• Subjects: Applied sciences; Building materials. Ceramics. Glasses; Ceramic industries; Chemical industry and chemicals; Exact sciences and technology; Miscellaneous; Technical ceramics
• ISSN: 0955-2219; 1873-619X
• DOI: 10.1016/S0955-2219(98)00004-1

Initial interest in aluminium titanate was due to its low thermal expansion coefficient and high thermal shock resistance, but further research was soon discouraged following the discovery of the expansion anisotropy and the instability of the compound over a specific range of temperatures. The development of a suitable active precursor powder could provide a possible solution to the fabrication difficulties (microcracking and decomposition). The scarce available thermodynamic data for the formation of Al 2TiO 5from its constituent oxides indicate that the reaction is endothermic and only possible at high temperature because of the titanate being entropy stabilised. The present work describes a straightforward combustion synthesis technique to prepare submicron Al 2TiO 5 powders, using the corresponding metal precursors-urea mixtures, at low temperature and short reaction times. A thermodynamic interpretation of the reaction is provided and the characteristics of the powder produced, like morphology, specific surface area and grain size, are discussed. The thermal behaviour of the combustion powder is compared with that of Al 2TiO 5 produced via the conventional ceramic solid state route.