Silica-alumina system: stable and metastable equilibria at 1. 0 atmosphere

Journal Article · Fri Jan 11 04:00:00 EDT 1974 · Science; (United States)

DOI:https://doi.org/10.1126/science.183.4120.69· OSTI ID:6060101

Aksay, I A; Pask, J A

Diffusion couples, consisting of sapphire and fused silica, which were annealed in the temperature range from 1678 to 2003/sup 0/C and analyzed by electron beam microprobe, have provided data on the stable phase equilibrium of the silica-alumina system. Under stable equilibrium conditions, the intermediate compound of this system, mullite (3Al/sub 2/O/sub 3/ x 2SiO/sub 2/), melts incongruently at 1828/sup 0/ +- 10/sup 0/C, and its solid solution field extends from 70.5 to 74.0 percent (by weight) alumina. The stable phase diagram is a composite of the two binary eutectic diagrams: silica-mullite in the absence of alumina and silica-alumina in the absence of mullite. Under metastable conditions, mullite melts congruently at approx. = 1890/sup 0/ +- 10/sup 0/C and its solid solution field extends to approx. = 83.2 percent (by weight) alumina.

• Research Organization: Univ. of California, Berkeley
• OSTI ID: 6060101
• Journal Information: Science; (United States), Journal Name: Science; (United States) Vol. 183; ISSN SCIEA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360202* -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
ANNEALING
CHALCOGENIDES
CRYSTAL STRUCTURE
DIAGRAMS
DIFFUSION
HEAT TREATMENTS
INORGANIC ION EXCHANGERS
ION EXCHANGE MATERIALS
LAYERS
MICROSTRUCTURE
MINERALS
MULLITE
OXIDES
OXYGEN COMPOUNDS
PHASE DIAGRAMS
PRECIPITATION
SEPARATION PROCESSES
SILICON COMPOUNDS
SILICON OXIDES