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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Crystal growth and viscous flow in barium disilicate glass

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Autor(es):
Rodrigues, Alisson M. [1] ; Cassar, Daniel R. [1] ; Fokin, Vladimir M. [1, 2] ; Zanotto, Edgar Dutra [1]
Número total de Autores: 4
Afiliação do(s) autor(es):
[1] Univ Fed Sao Carlos, CERTEV Ctr Res Technol & Educ Vitreous Mat, Dept Mat Engn, BR-13565905 Sao Carlos, SP - Brazil
[2] Univ Sao Paulo, Escola Engn Selo Carlos, Sao Paulo - Brazil
Número total de Afiliações: 2
Tipo de documento: Artigo Científico
Fonte: Journal of Non-Crystalline Solids; v. 479, p. 55-61, JAN 1 2018.
Citações Web of Science: 3
Resumo

Decoupling between the diffusion coefficients that control crystal growth (D-U) and viscous flow (D-eta) in deeply supercooled glass-forming liquids is one of the most celebrated, still unsolved, phenomena in glass science because it strongly impacts the analysis and prediction of crystallization kinetics. To further understand the decoupling phenomenon, we measured viscosity and crystal growth rates (of the crystalline surface layer growth and internally nucleated crystals) of a supercooled liquid with barium disilicate composition. We performed all measurements using glass samples from the same batch, a rare case that we call a ``clean{''} experiment. This type of analysis is uncommon, and its aim is to minimize the uncertainty due to the composition variation that is inherent in laboratory glass production. The decoupling temperature (T-d), the glass transition temperature (T-g), the melting point (T-m), and the liquid fragility index were obtained and successfully used to test a recently derived relationship which allows one to estimate T-d by knowing only T-m and the viscosity curve. We also show, for the first time, that the reduced decoupling parameter, which gauges the degree of deviation between D-U and D-eta, does not depend on the crystal growth mechanism for the cases of Normal or Screw Dislocation growth. (AU)

Processo FAPESP: 13/07793-6 - CEPIV - Centro de Ensino, Pesquisa e Inovação em Vidros
Beneficiário:Edgar Dutra Zanotto
Linha de fomento: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs