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Previous issue date: 2012-03-22 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Cells the solid oxide fuel are systems capable to directly convert energy of a chemical
reaction into electric energy in clean, quiet way and if its components in the solid state
differentiate of excessively the techniques for having all. Its more common geometric
configurations are: the tubular one and to glide. Geometry to glide beyond the usual
components (anode, cathode and electrolyte) needs interconnect and sealant. E the search for
materials adjusted for these components is currently the biggest challenge found for the
production of the cells. The sealants need to present chemical stability in high temperatures,
to provoke electric isolation, to have coefficient of compatible thermal expansion with the
excessively component ones. For presenting these characteristics the glass-ceramics materials
are recommended for the application. In this work the study of the partial substitution of the
ZrO2 for the Al2O3 in system LZS became it aiming at the formation of system LZAS, this
with the addition of natural spodumene with 10, 20 and 30% in mass. The compositions had
been casting to a temperature of 1500?C and later quickly cooled with the objective to
continue amorphous. Each composition was worn out for attainment of a dust with average
diameter of approximately 3?m and characterized by the techniques of DRX, FRX, MEV,
dilatometric analysis and particle size analysis. Later the samples had been conformed and
treated thermally with temperatures in the interval between 700-1000 ?C, with platform of 10
minutes and 1 hour. The analyses for the treated samples had been: dilatometric analysis,
DRX, FRX, electrical conductivity and tack. The results point with respect to the viability of
the use of system LZAS for use as sealant a time that had presented good results as isolating
electric, they had adhered to a material with similar ? of the components of a SOFC and had
presented steady crystalline phases / Pilhas a combust?vel de ?xido s?lido (PaCOS) s?o sistemas capazes de converter
energia de uma rea??o qu?mica diretamente em energia el?trica de maneira limpa, silenciosa e
se diferenciam das demais t?cnicas por ter todos os seus componentes no estado s?lido. Suas
configura??es geom?tricas mais comuns s?o: a tubular e a planar. A geometria planar al?m
dos componentes usuais (anodo, catodo e eletr?lito) necessita de interconectores e selantes. E
a busca por materiais adequados para esses componentes ? atualmente o maior desafio
encontrado para a produ??o das pilhas. Os selantes precisam apresentar estabilidade qu?mica
em altas temperaturas, provocar isolamento el?trico e ter coeficiente de dilata??o t?rmica
compat?vel com os demais componentes. Por apresentarem essas caracter?sticas os materiais
vitrocer?micos s?o os mais recomendados para a aplica??o. Neste trabalho fez-se o estudo da
substitui??o parcial da Zr02 pela Al2O3 no sistema LZS visando a forma??o do sistema LZAS,
isso com a adi??o 10, 20 e 30% em massa de espodum?nio natural. As composi??es foram
fundidas a uma temperatura de 1500?C e depois resfriadas rapidamente com o objetivo de
continuarem amorfas. Cada composi??o foi mo?da para obten??o de um p? com di?metro
m?dio de aproximadamente 3?m e caracterizada pelas t?cnicas de DRX, FRX, MEV,
dilatometria e granulometria. Posteriormente as amostras foram preparadas por compacta??o
e tratadas termicamente com temperaturas no intervalo entre 700-1000 ?C, com patamar de
10min e 1h. As an?lises para as amostras tratadas foram: dilatometria, DRX, FRX,
condutividade el?trica e ader?ncia. Os resultados apontam para a viabilidade do sistema
LZAS para uso como selante uma vez que apresentaram bons resultados como isolante
el?trico, aderiram a um material com coeficiente de dilata??o t?rmica (?) semelhante a dos
componentes de uma PaCOS e apresentaram fases cristalinas est?veis / 2020-01-01
| Identifer | oai:union.ndltd.org:IBICT/oai:repositorio.ufrn.br:123456789/12741 |
| Date | 22 March 2012 |
| Creators | Valcacer, Samara Melo |
| Contributors | CPF:05012180410, http://lattes.cnpq.br/9858094266525225, Silva, Gilson Garcia da, CPF:56634161453, http://lattes.cnpq.br/8681275097040450, Souza, Carlson Pereira de, CPF:13681389420, http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4781094H3, Gomes, Uilame Umbelino |
| Publisher | Universidade Federal do Rio Grande do Norte, Programa de P?s-Gradua??o em Ci?ncia e Engenharia de Materiais, UFRN, BR, Processamento de Materiais a partir do P?; Pol?meros e Comp?sitos; Processamento de Materiais a part |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Repositório Institucional da UFRN, instname:Universidade Federal do Rio Grande do Norte, instacron:UFRN |
| Rights | info:eu-repo/semantics/embargoedAccess |
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