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Directionally Crystallized Potassium Silicate Glass-Ceramic

Published online by Cambridge University Press:  15 February 2011

Grant Lu
Affiliation:
Ceramics Department Rutgers-The State University of New JerseyP. O. Box 909 Piscataway, NJ 08854USA
L. C. Klein
Affiliation:
Ceramics Department Rutgers-The State University of New JerseyP. O. Box 909 Piscataway, NJ 08854USA
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Abstract

Glasses in the potassium silicate system were directionally crystallized in a temperature gradient furnace. A composition of approximately 40 wt % K2O and 60 wt % SiO2 was used. Quenched glass samples were placed in alumina crucibles with K2O·2SiO2 seed crystals on the bottom surface. The crucible was translated from the hot zone to the cold zone of the furnace. A thermal gradient of 14°C/mm was maintained. Sample height was about 6 mm and translation rates were about 5 mm/h, 1.33 mm/h and 0.83 mm/h. Well-aligned crystals were observed to grow from the bottom of the crucible. Individual crystals were about 0.07 mm wide and extended the length of the crucible parallel to the thermal gradient. The degree of alignment was found to depend on initial temperature and translation rate. The samples have been studied using primarily optical microscopy.

Type
Research Article
Copyright
Copyright © Materials Research Society 1982

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References

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