| Full text | |
| Author(s): |
Pereira, G. J.
;
Florio, D. Z. de
;
Muccillo, E. N. S.
;
Gouvêa, Douglas
;
Castro, Ricardo Hauch Ribeiro de
[5]
Total Authors: 5
|
| Document type: | Journal article |
| Source: | Materials Letters; v. 59, n. 10, p. 1195-1199, Apr. 2005. |
| Field of knowledge: | Engineering - Materials and Metallurgical Engineering |
| Abstract | |
Reactive pure and manganese-doped (5% and 10 at.%) ceria nanosized powders were prepared by the polymeric precursor technique. Physical properties of powder materials were studied by X-ray diffraction, nitrogen adsorption, and diffuse reflectance infrared Fourier transform spectroscopy. Characterization of powder compacts after fast firing at 1200 °C for 5 min was carried out by scanning electron microscopy and impedance spectroscopy measurements. The bulk apparent density of sintered pellets was determined for pellets of different compositions sintered at 1200 °C. A gradual decrease of the particle size occurs with increasing doping content. Relatively high values of apparent density were obtained after fast firing doped specimens at 1200 °C. DRIFT spectra evidence that a fraction of Mn ions was segregated onto particles surface. The electrical resistivity of sintered pellets reveals different mechanisms of conduction depending on the Mn content. (AU) | |
| FAPESP's process: | 01/10053-7 - Influence of additives on the phase transformation and sintering of alumina |
| Grantee: | Ricardo Hauch Ribeiro de Castro |
| Support Opportunities: | Scholarships in Brazil - Doctorate (Direct) |
| FAPESP's process: | 99/10798-0 - Study of intergranular phenomena in ceramic oxides |
| Grantee: | Reginaldo Muccillo |
| Support Opportunities: | Research Projects - Thematic Grants |