Substituição total e parcial do quartzo por fontes alternativas de alumina na formulação e porcelanas.

The porcelains are multiphase materials produced with natural raw materials, containing less than 0.5% of residual porosity and having more than 10% volume of a glassy phase. The main porcelains are composed of kaolin-quartz-feldspar which are called triaxial porcelains. The use of alumina as a subs...

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Detalles Bibliográficos
Autor: Gralik, Guilherme
Tipo de recurso: tesis de maestría
Estado:Versión publicada
Fecha de publicación:2012
País:Brasil
Institución:Universidade Estadual de Ponta Grossa (UEPG)
Repositorio:Biblioteca Digital de Teses e Dissertações da UEPG
Idioma:portugués
OAI Identifier:oai:tede2.uepg.br:prefix/1417
Acceso en línea:http://tede2.uepg.br/jspui/handle/prefix/1417
Access Level:acceso abierto
Palabra clave:porcelana
alumina
microestrutura
resistência mecânica
quartzo
porcelain
microstructure
mechanical strength
quartz
CNPQ::ENGENHARIAS::ENGENHARIA DE MATERIAIS E METALURGICA
Descripción
Sumario:The porcelains are multiphase materials produced with natural raw materials, containing less than 0.5% of residual porosity and having more than 10% volume of a glassy phase. The main porcelains are composed of kaolin-quartz-feldspar which are called triaxial porcelains. The use of alumina as a substitute for quartz in the porcelain in of these formulations has been developed for some time. The results show a significant improvement in their mechanical properties, but alumina has a high cost compared with other raw materials. The study of the possibility of using alternative materials, that is also a source of alumina and with lower cost is quite important. In this work, quartz was substituted , in the formulation of triaxial porcelain, for alumina originating from the metallurgical process of aluminum in its various stages, beginning with the bauxite, followed by aluminum hydroxide obtained by two distinct processes (Reprecipitation and Bayer) and finally the alumina. The total and partial replacement was to evaluate the influence of quartz and raw materials in the formation of phases and mechanical properties of triaxial porcelain. The compositions studied were formed by pressing and sintered at different temperatures. The characterization of the porcelain was made by scanning electron microscopy, X-ray diffraction, mechanical strength by three point bending and measures of density, porosity and water absorption. The results showed that the use of raw bauxite, aluminum hydroxide and aluminum hydroxide Bayer reprecipitated as an alternative source of Al2O3 is viable and there is a considerable increase of mechanical strength both in partial replacement as in the substitution of quartz.