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Residual Stresses in Glasses

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 نشر من قبل Thomas Voigtmann
 تاريخ النشر 2013
  مجال البحث فيزياء
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The history dependence of the glasses formed from flow-melted steady states by a sudden cessation of the shear rate $dotgamma$ is studied in colloidal suspensions, by molecular dynamics simulations, and mode-coupling theory. In an ideal glass, stresses relax only partially, leaving behind a finite persistent residual stress. For intermediate times, relaxation curves scale as a function of $dotgamma t$, even though no flow is present. The macroscopic stress evolution is connected to a length scale of residual liquefaction displayed by microscopic mean-squared displacements. The theory describes this history dependence of glasses sharing the same thermodynamic state variables, but differing static properties.



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