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Published on: May 20, 2014
Mode-coupling analysis of residual stresses in colloidal glasses
S Fritschi1, M Fuchs, Th Voigtmann
1Fachbereich Physik, Universität Konstanz, 78457 Konstanz, Germany. thomas.voigtmann@dlr.de.
Soft Matter
|May 21, 2014
Summary
We found that residual stresses in colloidal glasses depend on shear flow history. This stress decay is governed by the prior shear rate, as confirmed by simulations and theory.
Area of Science:
- Condensed matter physics
- Materials science
- Statistical mechanics
Background:
- The glass transition is a fundamental phenomenon in condensed matter physics.
- Understanding the nonequilibrium relaxation of stresses in glassy materials is crucial for predicting their behavior.
- Colloidal systems serve as model systems for studying the glass transition.
Purpose of the Study:
- To investigate the nonequilibrium relaxation of stresses in a colloidal glass former after shear flow cessation.
- To determine the influence of shear history on residual stresses in an ideal glass.
- To compare theoretical predictions with simulation results.
Main Methods:
- Mode-coupling theory (MCT) was used to model the glass transition.
- Computer simulations, specifically Brownian dynamics, were employed for a 2D hard-disk system.
- Analysis focused on the relaxation of stresses after cessation of shear flow.
Main Results:
- Persistent residual stresses were observed in the ideal glass state.
- These residual stresses were found to be dependent on the prior shear flow history.
- The decay of stresses from a steady state to the residual stress level was governed by the previous shear rate.
Conclusions:
- The study provides insights into the memory effects in glassy materials.
- Mode-coupling theory offers a framework to rationalize the observed stress relaxation behavior.
- Brownian dynamics simulations qualitatively support the theoretical predictions, validating the model.
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