A theoretical and simulation approach to the rheology of magnetic suspensions
Dr. José Antonio Ruiz-López (Department of Applied Physics, University of Granada, Spain)

Magnetorheological (MR) fluids are smart materials whose rheological properties change in the presence of an external magnetic field [1]. The viscosity increases up to several orders of magnitude and, if the particle concentration and the magnetic field strength are high enough, it is necessary to overcome a stress threshold, the yield stress, to flow [2]. These tunable mechanical properties make MR fluids suitable in many industrial applications like vibration control and biomedical applications [3-4]. Several theoretical models have been proposed in the literature in order to explain the rheological behavior of MR fluids such as continuous medium [5], bi-continuous [6] and micromechanical models [7]. However, these models fail in the prediction of highly concentrated MR fluids. In this contribution, theoretical developments and particle-level simulations have been used to get a deeper understanding on the magnetorheological behavior of these suspensions in shear flow [8] and squeeze flow [9] modes.

Acknowledgements

MINECO MAT 2013-44429-R and PCIN 2015-051 projects (Spain), European Regional Development Fund (ERDF) and Junta de Andalucía P10-FQM-5977, P10-RNM-6630 and P11-FQM-7074 projects (Spain).

[1] Rabinow, J., AIEE Trans. 67, 1308-1315 (1946).

[2] de Vicente, J., D. J. Klingenberg and R. Hidalgo-Álvarez, Soft Matter 7, 3701-3710 (2011).

[3] Zhu, X., X. Jing and L. Cheng, J. Intell. Mater. Syst. Struct. 23(8), 839-873 (2012).

[4] Liu, J., G. A. Flores and R. Sheng, J. Magn. Magn. Mater. 225, 209-217 (2001).

[5] Berli, C. L. A., and J. de Vicente, Appl- Phys. Letters 101, 021903 (2012).

[6] Bossis, G., E. Lemaire and O. Volkova, J. Rheol. 41(3), 687-704 (1997).

[7] Volkova, O., G. Bossis, M. Guyot, V. Bashtovoi and A. Reks, J. Rheol. 44, 91-104 (2000).

[8] Ruiz López, J. A., J. C. Fernández-Toledano, D. J. Klingenberg, R. Hidalgo-Álvarez and J. de Vicente, J. Rheol. 60(1), 61-74 (2016).

[9] de Vicente, J., J. A. Ruiz-López, E. Andablo-Reyes, J. P. Segovia-Gutiérrez and R. Hidalgo-Álvarez, J. Rheol. 55(4), 753-779 (2011).