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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Preparation and Characterization of Mullite-Alumina Structures Formed ``In Situ{''} from Calcined Alumina and Different Grades of Synthetic Amorphous Silica

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Autor(es):
Fernandes, Leandro [1] ; Salomao, Rafael [1]
Número total de Autores: 2
Afiliação do(s) autor(es):
[1] Univ Sao Paulo, Escola Engn Sao Carlos, Dept Engn Mat, Ave Trabalhador Sao Carlense 400, Sao Carlos, SP - Brazil
Número total de Afiliações: 1
Tipo de documento: Artigo Científico
Fonte: MATERIALS RESEARCH-IBERO-AMERICAN JOURNAL OF MATERIALS; v. 21, n. 3 2018.
Citações Web of Science: 2
Resumo

The in situ reaction between alumina and silica to obtain mullite (Al6Si4O13) can be significantly affected by using synthetic amorphous silica (SAS) sources instead of crystalline ones (quartz and cristobalite). For instance, SASs promote early mullite formation (below 1300 degrees C) and greater densification during sintering. This paper reports the ``in situ{''} formation of mullite-alumina structures from fine calcined alumina (alpha-Al2O3) and four grades of SAS of different particles' morphology, specific surface area and internal porosity. After sintering assisted by dilatometry (up to 1500 degrees C), the samples' total porosity, density and flexural strength were measured. The relative density and strength levels of some of these structures were greater than or comparable to other studies in which similar compositions were sintered at higher temperatures (1600-1700 degrees C). Their microstructure assessment indicated that the specific surface area and internal porosity of SAS particles showed a major influence in the development of these physical properties. (AU)

Processo FAPESP: 10/19274-5 - Nova rota de sínteses de hidrotalcita (Mg6Al2(OH)16CO3.4H2O) a partir de suspensões aquosas de óxido de magnésio (MgO) e hidróxido de alumínio (Al(OH)3) e sua utilização em cerâmicas porosas para isolamento térmico em alta temperatura
Beneficiário:Rafael Salomão
Linha de fomento: Auxílio à Pesquisa - Apoio a Jovens Pesquisadores