| Texto completo | |
| Autor(es): |
Reis, Shirley L.
;
Carvalho, Sabrina G. M.
;
Muccillo, Eliana N. S.
;
Muccillo, Reginaldo
Número total de Autores: 4
|
| Tipo de documento: | Artigo Científico |
| Fonte: | CERAMICS-SWITZERLAND; v. 2, n. 2, p. 8-pg., 2019-06-01. |
| Resumo | |
CeO2:20 mol% Sm2O3 green ceramic pellets were sintered conventionally at 1500 degrees C/2 h and flash sintered by applying a 200 V cm(-1) electric field at 800 degrees C, 1000 degrees C and 1200 degrees C. The thickness shrinkage of the pellets was followed bythe specimen being positioned inside a dilatometer adapted with platinum electrodes and terminal leads connected to a power supply for application of the electric voltage. The microstructure of the surfaces of the sintered samples were observed in a scanning electron microscope. The electrical properties were evaluated by the impedance spectroscopy technique in the 5 Hz-13 MHz frequency range from 210 degrees C to 280 degrees C. The main results show that (i) the final shrinkage level is nearly independent of the temperature when the electric field is applied and slightly better than that of the 1500 degrees C sintered pellet, and (ii) the bulk conductivity of the sample flash sintered at 1200 degrees C is similar to that of the sample sintered at 1500 degrees C. The availability of a pathway for the electric current pulse derived from the applied electric field is proposed as the reason for the achieved shrinkages. Scavenging of the grain boundaries by Joule heating is proposed as the reason for the improved oxide ion bulk conductivity. (AU) | |
| Processo FAPESP: | 17/11937-4 - Rota sustentável para a conversão de metano com tecnologias eletroquímicas avançadas |
| Beneficiário: | Fabio Coral Fonseca |
| Modalidade de apoio: | Auxílio à Pesquisa - Programa Centros de Pesquisa em Engenharia |
| Processo FAPESP: | 13/07296-2 - CDMF - Centro de Desenvolvimento de Materiais Funcionais |
| Beneficiário: | Elson Longo da Silva |
| Modalidade de apoio: | Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs |