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Elongated micro-structures in magneto-sensitive elastomers: a dipolar mean field model.
Dirk Romeis1, Vladimir Toshchevikov1, Marina Saphiannikova1
1Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Strasse 6, 01069 Dresden, Germany. romeis@ipfdd.de.
Soft Matter
|November 5, 2016
Summary
Researchers developed a mean field approach to model micro-structures in magneto-sensitive elastomers. This model efficiently predicts sample behavior and shape changes under external magnetic fields.
Area of Science:
- Materials Science
- Physics of Polymers
- Magnetism
Background:
- Magneto-sensitive elastomers (MSEs) contain magnetizable micro-particles.
- Understanding micro-particle arrangement is key to MSE behavior.
- Mutual magnetic interactions influence micro-structure formation.
Purpose of the Study:
- To develop a mean field approach for modeling micro-particle arrangements in MSEs.
- To efficiently calculate MSE sample behavior considering micro-structure and shape effects.
- To predict deformation and shape changes in MSEs under external magnetic fields.
Main Methods:
- Dipole model for magnetic interactions.
- Mean field theory application.
- Analysis of micro-structure orientation relative to external magnetic fields.
Main Results:
- The approach accurately describes particle arrangement into elongated micro-structures.
- Efficient calculation of MSE behavior is achieved when micro-structures align with the magnetic field.
- Comprehensive phase diagrams for deformation were generated.
- Discontinuous shape change predicted for oblate MSE samples.
Conclusions:
- The developed mean field approach is effective for MSEs with aligned micro-structures.
- The interplay of micro-structure and shape significantly impacts MSE behavior.
- MSEs, particularly oblate ones, exhibit predictable, sometimes discontinuous, shape changes in magnetic fields.
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