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Measuring Material Microstructure Under Flow Using 1-2 Plane Flow-Small Angle Neutron Scattering
Published on: February 6, 2014
Jamming transition as probed by quasistatic shear flow.
Claus Heussinger1, Jean-Louis Barrat
1Université de Lyon, CNRS, UMR 5586, 69622 Villeurbanne, France.
Physical Review Letters
|June 13, 2009
Summary
This study reveals how amorphous particle packings transition from flowing to solid-like behavior near jamming. Researchers found a critical packing fraction where yield-stress emerges, exhibiting properties of isostatic solids.
Area of Science:
- Physics
- Materials Science
- Rheology
Background:
- Amorphous solids exhibit complex rheological behaviors near the jamming transition.
- Understanding the transition from flowing to solid-like states is crucial for materials science.
Purpose of the Study:
- To investigate the rheology of amorphous packings of soft, frictionless particles near the jamming point.
- To identify the critical packing fraction and associated scaling laws at the jamming transition.
- To characterize the nature of long-range correlations in different phases relative to the transition.
Main Methods:
- Utilizing a quasistatic simulation method to generate an ensemble of states.
- Directly sampling system states at their yield stress.
- Analyzing the system's behavior across a range of packing fractions.
Main Results:
- A continuous jamming transition was observed at a specific packing fraction.
- The system transitions from a freely flowing state to a yield-stress state.
- Scaling laws characteristic of isostatic solids were identified near the transition.
Conclusions:
- The jamming transition in these systems is continuous and occurs at a well-defined packing fraction.
- Isostaticity governs long-range correlations below the transition.
- Above the transition, correlations are characteristic of dense, disordered elastic media.
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