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RESEARCH PRODUCT

Thermal evolution and structural study of 2:1 mullite from monophasic gels

Francisco Jose TorresJavier AlarcónEsther Ruiz De Sola

subject

DiffractionMaterials scienceInfraredMulliteAluminium nitrateGrain sizeCrystallographyHydrolysischemistry.chemical_compoundChemical engineeringchemistryReagentMaterials ChemistryCeramics and CompositesSpectroscopy

description

Abstract Single phase mullite gels with composition 2Al 2 O 3 ·SiO 2 (2:1) were prepared by the slow hydrolysis method using aluminium nitrate nonahydrate and tetraethylorthosilicate as reagents. The evolution to mullite from gels was studied by infrared (IR) spectroscopy and X-ray diffraction (XRD). Gels thermally treated under fast schedules showed mullite formation below 900 °C. Compositional and microstructural changes in 2:1 mullites through the range of temperature from 900 to 1600 °C were determined by the measurement of lattice parameters and field emission scanning electron microscopy. The alumina-rich mullites formed at low temperatures become almost the nominal 2:1 at 1600 °C. This result is consistent with available thermodynamic data for mullite formation from alumina and silica. Microstructural examination indicated an almost constant grain size for mullite from 900 to 1600 °C.

yearjournalcountryeditionlanguage
2006-01-01Journal of the European Ceramic Society
https://doi.org/10.1016/j.jeurceramsoc.2005.04.015