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无机材料学报 2005
Nucleation and Crystallization Mechanism of TeO2-Nb2O5-AgCl Glass under Auxiliary Electric Field
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Abstract:
To control nucleation and crystallization of glass exactly is one of key steps for preparing nano-crystalline embedded glass. The auxiliary electric field, applied on the glass, which is in thermal treatment process, may accelerate nucleation and crystallization of glass when the dielectric coefficient of the glass is less than that of crystalline. On the contrary, the nucleation and crystallization of glass will be inhibited. The auxiliary electric field, whether it plays an accelerating or inhibiting effect on glass, can be used to control nucleation and crystallization exactly when preparing nano-crystalline embedded glass. The mechanism of effects of auxiliary electric field and temperature field on nucleation and crystallization of glass was deduced. Their effects on TeO2-Nb2O5-AgCl glass were also studied in this paper. The results show that the electric field can aid the glass to nucleate in the temperature little lower than traditional nucleation region. The speed of crystallization can be accelerated under auxiliary electric field. The electric field can stimulate nucleation and crystallization of Te02-Nb2O5-AgCl glass under little below corresponding temperature, which can not provide with enough activation energy for nucleation and crystallization. The characteristic of very fast loading and unloading of auxiliary electric field will become a kind of " switch " to control the nucleation and crystallization of the glass. The " switch " will be used to control the growth of nano-crystallines in the glass accurately.