Synthesis and sintering at low temperature of a new nanostructured beta-Eucryptite dense compact by spark plasma sintering

The solid state reaction between kaolin and Li2CO3 with a 1:1 M composition has been studied in the temperature range 380°C-550 °C. The role played by Li2CO3 (basic medium) in the thermal transformation of the kaolin has been investigated by X-Ray diffraction, FESEM, TEM, MAS-NMR and XPS techniques....

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Detalhes bibliográficos
Autores: Suárez, Marta, Fernández, Adolfo, Díaz, Luis A., Sobrados, Isabel, Sanz Lázaro, Jesús, Borrell, Amparo, Palomares, F. Javier, Torrecillas, Ramón, Moya, J. S.
Formato: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2020
País:España
Recursos:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/219262
Acesso em linha:http://hdl.handle.net/10261/219262
Access Level:acceso abierto
Palavra-chave:Spark plasma sintering
Geopolymer
Kaolin
β-Eucryptite
Descrição
Resumo:The solid state reaction between kaolin and Li2CO3 with a 1:1 M composition has been studied in the temperature range 380°C-550 °C. The role played by Li2CO3 (basic medium) in the thermal transformation of the kaolin has been investigated by X-Ray diffraction, FESEM, TEM, MAS-NMR and XPS techniques. For the first time, a nanostructured high density β- Eucryptite (<10 nm) has been obtained by Spark Plasma Sintering (SPS) at 550 °C in high vacuum. The atmosphere used in sintering treatments has a determinant role in lithium migration and crystallization of β- Eucryptite. In the case of low vacuum treatments, an amorphous LiAlSiO4 geopolymer type material was obtained. Due to exclusive properties and performances of β- Eucryptite based materials, the results reported in the present investigation open new perspectives for new nanostructured and amorphous functional materials with null thermal expansion, ionic conduction and remarkable mechanical properties.