Abstract
Extensive neutron diffraction and Rietveld studies of dense, hot pressed mullite (3Al2O3·2SiO2) have been conducted up to 1650 °C in air, yielding a complete set of lattice parameters and axial thermal expansion coefficients. Unconstrained powders of the same stoichiometric composition were also analyzed by X-ray diffraction and Rietveld techniques up to 900 °C in air, from which lattice parameters and thermal expansion coefficients were obtained. An earlier reported structural discontinuity was confirmed by XRD to lie in the temperature range 425 to 450 °C. Single-crystalline mullite fibers of composition 2·5Al2O3·SiO2 were grown from the melt by a laser-heated, float zone method. A partial set of the single-crystal elastic moduli were determined from various sections of fiber, by Brillouin spectroscopy, from room temperature up to 1400 °C. They indicated a roughly 10\% reduction in stiffness over that temperature range.
Dokumententyp: | Zeitschriftenartikel |
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Fakultät: | Geowissenschaften > Department für Geo- und Umweltwissenschaften > Kristallographie und Materialwissenschaft |
Themengebiete: | 500 Naturwissenschaften und Mathematik > 550 Geowissenschaften, Geologie |
Sprache: | Englisch |
Dokumenten ID: | 18681 |
Datum der Veröffentlichung auf Open Access LMU: | 10. Mrz. 2014, 14:12 |
Letzte Änderungen: | 29. Apr. 2016, 09:15 |