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arXiv · 1211.6964

On the Bauschinger effect in supercoooled melts under shear: results from mode coupling theory and molecular dynamics simulations

Fabian Frahsa·Amit Kumar Bhattacharjee·Jürgen Horbach·Matthias Fuchs·Thomas Voigtmann
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Abstract

We study the nonlinear rheology of a glass-forming binary mixture under the reversal of shear flow using molecular dynamics simulations and a schematic model of the mode-coupling theory of the glass transition (MCT). Memory effects lead to a history-dependent response, as exemplified by the vanishing of a stress-overshoot phenomenon in the stress--strain curves of the sheared liquid, and a change in the apparent elastic coefficients around states with zero stress. We investigate the various retarded contributions to the stress response at a given time schematically within MCT. The connection of this macroscopic response to single-particle motion is demonstrated using molecular-dynamics simulation.

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Fabian Frahsa, Amit Kumar Bhattacharjee, Jürgen Horbach, Matthias Fuchs, Thomas Voigtmann. 2012-11-29. On the Bauschinger effect in supercoooled melts under shear: results from mode coupling theory and molecular dynamics simulations. https://doi.org/10.1063/1.4770336

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