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How colloid-colloid interactions and hydrodynamic effects influence the percolation threshold: A simulation study in
Aleena Maria Laganapan1, Mohamed Mouas1, Arnaud Videcoq1
1SPCTS, UMR 7315, ENSCI, CNRS, Centre Européen de la Céramique, 12 rue Atlantis, 87068 Limoges cedex, France.
Journal of Colloid and Interface Science
|August 2, 2015
Summary
Computer simulations reveal that stronger colloid attraction decreases the percolation threshold (ϕc) in alumina suspensions. Hydrodynamic interactions (HIs) reduce ϕc by promoting elongated structures, especially when attraction is weak.
Area of Science:
- Colloid Science
- Materials Science
- Computational Physics
Background:
- Percolation phenomena are critical in understanding the formation of networks in colloidal suspensions.
- Alumina suspensions are widely used in ceramics and other advanced materials, making their behavior crucial to study.
Purpose of the Study:
- To investigate the percolation behavior of alumina suspensions using computer simulations.
- To determine the influence of colloid-colloid attraction and hydrodynamic interactions (HIs) on the percolation threshold (ϕc).
Main Methods:
- Utilized computer simulations to model alumina suspensions.
- Employed Brownian Dynamics (BD) and Stochastic Rotation Dynamics-Molecular Dynamics (SRD-MD) to compare simulations with and without hydrodynamic interactions.
- Calculated the percolation threshold (ϕc) under varying conditions.
Main Results:
- Percolation threshold (ϕc) decreases as colloid-colloid attraction strength increases.
- Hydrodynamic interactions (HIs) lead to more elongated aggregate structures.
- HIs significantly decrease ϕc when colloid-colloid attraction is weak, but their effect diminishes with stronger attraction.
- Simulated ϕc values align well with predictions from the yield stress model.
Conclusions:
- Colloid-colloid attraction is a primary factor controlling percolation in alumina suspensions.
- Hydrodynamic interactions play a significant role in modifying percolation behavior, particularly in less attractive systems.
- The findings provide valuable insights for controlling the microstructure and properties of alumina-based materials.
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