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Updated: Jul 9, 2026
10:56
Confocal Imaging of Confined Quiescent and Flowing Colloid-polymer Mixtures
Published on: May 20, 2014
Structural rearrangements that govern flow in colloidal glasses.
Peter Schall1, David A Weitz, Frans Spaepen
1Van der Waals-Zeeman Institute, University of Amsterdam, Valckenierstraat 65, 1018 XE Amsterdam, Netherlands. pschall@science.uva.nl
Science (New York, N.Y.)
|December 22, 2007
Summary
Researchers visualized structural rearrangements in colloidal glasses under shear. They identified localized shear transformation zones, revealing how strain and thermal fluctuations influence glass properties.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Rheology
Background:
- Structural rearrangements are key to glass properties like flow resistance, heat capacity, and dielectric constant.
- Direct visualization of these rearrangements in atomic glasses remains challenging.
Purpose of the Study:
- To directly image thermally induced structural rearrangements in glasses under applied shear.
- To characterize the formation energy and topology of shear transformation zones.
Main Methods:
- Utilized a colloidal glass system for direct three-dimensional imaging.
- Applied shear stress to induce structural rearrangements.
- Employed continuum models to analyze the underlying physics.
Main Results:
- Identified localized, irreversible shear transformation zones.
- Determined the formation energy and topology of these zones.
- Observed that transformations can promote subsequent nearby transformations.
Conclusions:
- Direct visualization of structural rearrangements in colloidal glasses is achievable.
- The interplay of applied strain and thermal fluctuations governs shear zone formation in glasses.
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