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It is generally known that every commercial glass has its own crystallization ability it means that a certain temperature
interval exists and glasses can crystallize in this interval. We have to know the crystallization ability and crystallization
speed to choose the proper regime for glass melting, manufacturing of different articles and for thermal processing in
glass-ceramics manufacture. Crystallization character depends on relation between crystallization centers formation rate,
crystal growing rate from this centers and viscosity. The larger the interval between peak rates of crystal growth and
formation of crystallization centers, and lower the rates themselves, the lower the tendency of glass to crystallization.
Crystallization of glass materials depends on several factors: chemical composition and viscosity of glass, basic material,
mutual solubility of every component, duration of exposure on proper temperatures, existence of crystallization catalysts
and conditions of thermal processing of glass. To get crystallization conditions one have to provide slow passing through
the temperature interval 1000-1200°C.
Earlier the possibility of glass-ceramic crystallization under that CO2 laser action was experimentally shown. But even
now it is not clear enough how crystallization centers can form and grow in such a small period of time (several seconds)
and what role do impurity materials play (i.e. Au, Ag, etc.). It is known that their atoms play role of crystallization
centers in conventional regimes of glass-ceramic crystallization. So, to make a step forward in understanding the laser
crystallization process of different glasses we decided to check the assumption of vacancy model that any glass can be
crystallized during several seconds regardless of above mentioned impurity materials presence.
We decided to choose a glass material for our experiment with large crystallization temperature interval and without any
impurity materials like Au, Ag or Ti: Li2O•2SiO2 glass. In this paper we'd like to show the results of our investigation.
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