Seeding effects on crystallization of KAlSi[sub 3]O[sub 8], RbAlSi[sub 3]O[sub 8], and CsAlSi[sub 3]O[sub 8] gels and glasses

Journal Article · Thu Dec 01 00:00:00 EST 1994 · Journal of the American Ceramic Society; (United States)

DOI:https://doi.org/10.1111/j.1151-2916.1994.tb04556.x· OSTI ID:6870912

Liu, C; Komarneni, S; Roy, R ^[1]

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1. Pennsylvania State Univ., University Park, PA (United States). Materials Research Lab.

Crystallization of stoichiometric KAlSi[sub 3]O[sub 8], RbAlSi[sub 3]O[sub 8], and CsAlSi[sub 3]O[sub 8] gels (single-phase and multiphase gels) and glasses with and without seeding has been investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectrometry (EDS). The pure gels of K-, Rb-, and Cs-feldspar compositions crystallized mainly to leucite (KAlSi[sub 2]O[sub 6]), a Rb analogue of leucite (RbAlSi[sub 2]O[sub 6]), and pollucite (CsAlSi[sub 2]O[sub 6]), a Rb analogue of leucite (RbAlSi[sub 2]O[sub 6]), and pollucite (CsAlSi[sub 2]O[sub 6]), respectively. The KAlSi[sub 3]O[sub 8] glass also yielded leucite. No feldspar phases crystallized in the temperature region studied. The leucite crystallization temperature was lowered by using multi-phase gels. The crystallization sequence of the KAlSi[sub 3]O[sub 8] glasses and single-phase gels did not change upon seeding with isostructural feldspar crystals. No significant crystallization effects were detected with the use of RbAlSi[sub 3]O[sub 8] and CsAlSi[sub 3]O[sub 8] multiphasic gels. However, K-feldspar (sanidine) was crystallized by using both compositionally and structurally different gels of KAlSi[sub 3]O[sub 8], i.e., multiphase gels seeded with feldspar crystals. The microstructure of oriented sanidine crystals around the seeds indicated an epitaxial crystallization mechanism.

• OSTI ID: 6870912
• Journal Information: Journal of the American Ceramic Society; (United States), Vol. 77:12; ISSN 0002-7820
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM SILICATES
CRYSTALLIZATION
CESIUM SILICATES
COMPOSITE MATERIALS
POTASSIUM SILICATES
RUBIDIUM SILICATES
AMORPHOUS STATE
CRYSTAL STRUCTURE
DISPERSIONS
MICROSTRUCTURE
PRECIPITATION
TEMPERATURE RANGE 0400-1000 K
ALKALI METAL COMPOUNDS
ALUMINIUM COMPOUNDS
CESIUM COMPOUNDS
MATERIALS
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
POTASSIUM COMPOUNDS
RUBIDIUM COMPOUNDS
SEPARATION PROCESSES
SILICATES
SILICON COMPOUNDS
TEMPERATURE RANGE
360601* - Other Materials- Preparation & Manufacture
360602 - Other Materials- Structure & Phase Studies