Browse by author
Lookup NU author(s): Emeritus Professor Derek Thompson
Full text for this publication is not currently held within this repository. Alternative links are provided below where available.
Recent studies on rare earth densified α-sialon ceramics have shown that the resulting α-sialon product, present either as a single phase or in conjunction with β-sialon, is unstable when heat treated at lower (1350-1600°C) temperatures, and transforms to a mixture of β-sialon plus other crystalline or liquid metal sialon phases. The present paper describes similar studies carried out on calcium-densified α-sialon compositions, and shows that for a wide range of starting compositions, with calcium as the sole sintering additive or present with other (Nd, Sr) cations, the resulting calcium stabilised a-sialon products are fully resistant towards α→β transformation when heat treated in the temperature range 1450-1550°C. Whereas α→β transformation in rare earth stabilised α-sialons is influenced by the nature of the rare earth cation, the α-sialon composition, the composition and melting behaviour of the liquid phase and the presence or absence of β-sialon nuclei, transformation in calcium a-sialons appears to be influenced by none of these parameters. Clearly if α→β sialon transformation occurs in this system, the transformation temperature for calcium α-sialons must be below 1450°C, the heat-treatment temperature which has been most frequently used in current research on rare earth densified α-sialons.
Author(s): Mandal H, Thompson DP
Publication type: Article
Publication status: Published
Journal: Journal of the European Ceramic Society
Year: 1999
Volume: 19
Issue: 5
Pages: 543-552
Print publication date: 01/05/1999
ISSN (print): 0955-2219
ISSN (electronic): 1873-619X
Publisher: Elsevier Ltd
URL: http://dx.doi.org/10.1016/S0955-2219(98)00251-9
DOI: 10.1016/S0955-2219(98)00251-9
Altmetrics provided by Altmetric
