Phase Diagram for Mullite-SiF4

Phase Diagram for Mullite-SiF4

At 1 atm of SiF4, mullite and SiF4 react below 660° 7°C to form A1F3 and SiO2. From 660° to 1056°± 5°C, the product is fluorotopaz. Mullite is stable in the presence of 1 atm of SiF4 above 1056°C. The transition temperatures at other pressures of SiF4 can be calculated from log p(atm) = 11.587 – 108...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:Journal of the American Ceramic Society 1995-12, Vol.78 (12), p.3253-3258
1. Verfasser: Moyer, John R.
Format: Artikel
Sprache:eng
Schlagworte:
Chemistry
Exact sciences and technology
General and physical chemistry
Liquid-solid equilibria
Phase equilibria
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:At 1 atm of SiF4, mullite and SiF4 react below 660° 7°C to form A1F3 and SiO2. From 660° to 1056°± 5°C, the product is fluorotopaz. Mullite is stable in the presence of 1 atm of SiF4 above 1056°C. The transition temperatures at other pressures of SiF4 can be calculated from log p(atm) = 11.587 – 10811/T(K) and log p(atm) = 9.9609 – 13238/T(K). The phase diagram shows only gas–solid equilibria, but there is evidence for a metastable melt from which acicular mullite and fluorotopaz grow.
ISSN:0002-7820
1551-2916
DOI:10.1111/j.1151-2916.1995.tb07961.x