Initial magnetic susceptibility of the diluted magnetopolymer elastic composites

• Published in: Journal of magnetism and magnetic materials Vol. 431; pp. 115 - 119
• Main Authors: Borin, D.Yu, Odenbach, S.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.06.2017; Elsevier BV
• Subjects: Anisotropy; Approximation; Chains; Dilution; Magnetic permeability; Magnetic properties; Magnetic susceptibility; Magnetism; Magnetopolymer elastic composites; Magnetorheology; Mathematical analysis; Microparticles; Microstructure; Particulate composites; Polymers; Magnetorheology; Microstructure; Magnetopolymer elastic composites; Magnetic susceptibility
• ISSN: 0304-8853; 1873-4766
• DOI: 10.1016/j.jmmm.2016.07.055

In this work diluted magnetopolymer elastic composites based on magnetic microparticles are experimentally studied. Considered samples have varied concentration of the magnetic powder and different structural anisotropy. Experimental data on magnetic properties are accomplished by microstructural observations performed using X-Ray tomography. Influence of the particles amount and structuring effects on the initial magnetic susceptibility of the composites as well as the applicability of the Maxwell-Garnett approximation, which is widely used in considerations of magnetopolymer elastic composites, are evaluated. It is demonstrated that the approximation works well for diluted samples containing randomly distributed magnetic particles and for the diluted samples with chain-like structures oriented perpendicular to an externally applied field, while it fails to predict the susceptibility of the samples with structures oriented parallel to the field. Moreover, it is shown, that variation of the chains morphology does not significantly change the composite initial magnetic susceptibility. •The Maxwell-Garnet prediction works well for the diluted isotropic composites.•The Maxwell-Garnet prediction can be used for composites with structures oriented perpendicular to an applied field.•Chains oriented parallel to an applied field significantly increase the composite initial magnetic susceptibility.•The number and thickness of chains is not of the highest importance for the diluted composites.•The crucial reason of the observed effect is expected to be the demagnetisation factor of the chains.