Inverse magnetorheological fluids / Rodriguez-Arco L.,Lopez-Lopez M. T.,Zubarev A. Y.,Gdula K.,Duran J. D. G. // SOFT MATTER. - 2014. - V. 10, l. 33. - P. 6256-6265.

ISSN/EISSN:

1744-683X / 1744-6848

Type:

Article

Abstract:

We report a new kind of field-responsive fluid consisting of suspensions of diamagnetic (DM) and ferromagnetic (FM) microparticles in ferrofluids. We designate them as inverse magnetorheological (IMR) fluids for analogy with inverse ferrofluids (IFFs). Observations on the particle self-assembly in IMR fluids upon magnetic field application showed that DM and FM microparticles were assembled into alternating chains oriented along the field direction. We explain such assembly on the basis of the dipolar interaction energy between particles. We also present results on the rheological properties of IMR fluids and, for comparison, those of IFFs and bidispersed magnetorheological (MR) fluids. Interestingly, we found that upon magnetic field application, the rheological properties of IMR fluids were enhanced with respect to bidispersed MR fluids with the same FM particle concentration, by an amount greater than the sum of the isolated contribution of DM particles. Furthermore, the field-induced yield stress was moderately increased when up to 30\% of the total FM particle content was replaced with DM particles. Beyond this point, the dependence of the yield stress on the DM content was non-monotonic, as expected for FM concentrations decreasing to zero. We explain these synergistic results by two separate phenomena: the formation of exclusion areas for FM particles due to the perturbation of the magnetic field by DM particles and the dipole-dipole interaction between DM and FM particles, which enhances the field-induced structures. Based on the second phenomenon, we present a theoretical model for the yield stress that semi-quantitatively predicts the experimental results.

Author keywords:

BEHAVIOR; SUSPENSIONS; FERROFLUID; FLOW

DOI:

10.1039/c4sm01103a

Web of Science ID:

ISI:000340438600014

Соавторы в МНС:

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Другие поля

Поле	Значение
Publisher	ROYAL SOC CHEMISTRY
Address	THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND
Language	English
EISSN	1744-6848
Keywords-Plus	BEHAVIOR; SUSPENSIONS; FERROFLUID; FLOW
Research-Areas	Chemistry; Materials Science; Physics; Polymer Science
Web-of-Science-Categories	Chemistry, Physical; Materials Science, Multidisciplinary; Physics, Multidisciplinary; Polymer Science
Author-Email	modesto@ugr.es
ResearcherID-Numbers	Lopez-Duran, Juan de Dios/M-2774-2014 Lopez-Lopez, Modesto T/K-7327-2012 Rodriguez-Arco, Laura/K-6056-2014
ORCID-Numbers	Lopez-Duran, Juan de Dios/0000-0002-5586-1276 Lopez-Lopez, Modesto T/0000-0002-9068-7795 Rodriguez-Arco, Laura/0000-0002-5527-7547
Funding-Acknowledgement	Russian Fund of Fundamental Investigations {[}12-01-00132, 13-02-91052, 13-01-96047, 14-08-00283]; Ministry of Education of Russian Federation {[}2.1267.2011]; Government of the Russian Federation {[}02.A03.21.0006]; Secretaria de Estado de Educacion, Formacion Profesional y Universidades (MECD, Spain) through its FPU program
Funding-Text	Projects 12-01-00132, 13-02-91052, 13-01-96047, and 14-08-00283 (Russian Fund of Fundamental Investigations), 2.1267.2011 (Ministry of Education of Russian Federation), and the Act 211 (Government of the Russian Federation no. 02.A03.21.0006). The University of Granada (Accion Integrada con Rusia; Plan Propio 2011). L. Rodriguez-Arco acknowledges financial support from Secretaria de Estado de Educacion, Formacion Profesional y Universidades (MECD, Spain) through its FPU program.
Number-of-Cited-References	28
Usage-Count-Last-180-days	2
Usage-Count-Since-2013	24
Journal-ISO	Soft Matter
Doc-Delivery-Number	AN2TQ