Structural heterogeneity and pressure-relaxation in compressed borosilicate glasses by in situ small angle X-ray scattering

Language
en
Document Type
Article
Issue Date
2012-11-06
Issue Year
2011
Authors
Reibstein, Sindy
Wondraczek, Lothar
Ligny, D. de
Krolikowski, Sebastian
Sirotkin, S.
Simon, J.-P.
Martinez, V.
Champagnon, B.
Editor
Abstract

We report on Brillouin and in situ small angle X-ray scattering (SAXS) analyses of topological heterogeneity in compressed sodium borosilicate glasses. SAXS intensity extrapolated to very low angular regimes, I(q = 0), is related to compressibility. From Brillouin scattering and analyses of the elastic properties of the glass, the Landau-Placzek ratio is determined and taken as a direct reflection of the amplitude of frozen-in density fluctuations. It is demonstrated that with increasing fictive pressure, topological (mid- and long-range) homogeneity of the glass increases significantly. Heating and cooling as well as isothermal scans were performed to follow the evolution of density fluctuations upon pressure recovery. For a sample with a fictive pressure pf of 470 MPa, complete recovery to pf = 0.1 MPa was observed to occur close to the glass transition temperature. The values of fictive and apparent fictive temperature, respectively, as obtained via the intersection method from plots of I(q = 0) vs. temperature were found in good agreement with previous calorimetric analyses. Isothermal scans suggest that mid- and long-range recovery govern macroscopic density relaxation.

Journal Title
Journal of Chemical Physics 134.20 (2011): 05.11.2012 <http://jcp.aip.org/resource/1/jcpsa6/v134/i20/p204502_s1>
Citation
Journal of Chemical Physics 134.20 (2011): 05.11.2012 <http://jcp.aip.org/resource/1/jcpsa6/v134/i20/p204502_s1>
DOI
Document's Licence
Zugehörige ORCIDs