Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10630205 | Journal of the European Ceramic Society | 2005 | 14 Pages |
Abstract
Solid solutions of the pseudo-ternary system Ce0.6/(1+x)Zr(Hf)(0.4âx)/(1+x)Ta2x/(1+x) (0.00 ⤠x ⤠0.06), i.e. having molecular composition 1, 2, 3, 4, 5 and 6% in Ta2O5, have been prepared by traditional ceramic methods (1500 °C for 3 h). SEM observations and analysis of the X-ray diffraction powders allowed to establish that the solubility of Ta2O5 in the above mentioned system is 4 %mol. The Rietveld analysis of the powder X-ray diffraction data has shown that all the samples of the solid solution crystallize in tetragonal space group P42/nmc (No. 137) but are nearly cubic, space group Fm3¯m (No. 225). The freshly prepared specimens (from 1 to 4 %mol of Ta2O5) show additional peaks due to a tetragonal supercell and also to a modulated structure. However, the modulated peaks disappear after 8 months. Compositions containing 5 and 6% of Ta2O5 show also additional peaks due to a small quantity of two crystalline phases having approximate composition: ZrO2-2CeO2-Ta2O5 and 2CeO2-Ta2O5 (later on identified as CeTaO4).
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
Dore Augusto Clemente, Elio Lucchini, Sergio Meriani, Noella Furlan,