Characterization of the glass transition in vitreous silica by temperature scanning small-angle X-ray scattering

Université Montpellier 2 Sciences et Techniques, Montpelhièr, Languedoc-Roussillon, France
EPL (Europhysics Letters) (Impact Factor: 2.1). 04/2005; 70(2). DOI: 10.1209/epl/i2004-10481-1
Source: arXiv


The temperature dependence of the x-ray scattering in the region below the first sharp diffraction peak was measured for silica glasses with low and high OH content (GE-124 and Corning 7980). Data were obtained upon scanning the temperature at 10, 40 and 80 K/min between 400 K and 1820 K. The measurements resolve, for the first time, the hysteresis between heating and cooling through the glass transition for silica glass, and the data have a better signal to noise ratio than previous light scattering and differential thermal analysis data. For the glass with the higher hydroxyl concentration the glass transition is broader and at a lower temperature. Fits of the data to the Adam-Gibbs-Fulcher equation provide updated kinetic parameters for this very strong glass. The temperature derivative of the observed X-ray scattering matches that of light scattering to within 14%.

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Available from: Ralf Brüning, May 06, 2013
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