Controlling the coarsening dynamics of ferrogranular networks by means of a vertical magnetic field

Author(s)
Matthias Biersack, Ali Lakkis, Reinhard Richter, Oksana Bilous, Pedro A. Sánchez, Sofia S. Kantorovich
Abstract

We are exploring in experiments the aggregation process in a shaken granular mixture of glass and magnetized steel beads, filled in a horizontal vessel, after the shaking amplitude is suddenly decreased. Then the magnetized beads form a transient network that coarsens in time into compact clusters, resembling a viscoelastic phase separation [Tanaka, J. Phys.: Condens. Matter 12, R207 (2000)0953-898410.1088/0953-8984/12/15/201], where attached beads represent the slow phase. Here we investigate how a homogeneous magnetic field oriented in vertical direction impedes the emergence and growth of the networks. With increasing field amplitude this phase is replaced by a fluctuating arrangement of repelling, isolated steel beads. The experimental results are compared with those of computer simulations. Coarse-grained molecular dynamics confirms the impact of an applied magnetic field on the structural transitions and allows us to investigate long-time regimes and magnetic response not yet accessible in the experiment. It turns out that an applied magnetic field has different impacts, depending on it strength. It can be used either to slow down the dynamics of the structural transitions without changing the type of the resulting phases and only affecting the amount and sizes of clusters, or to fully impede the formation of network-like and compact aggregates of steel beads.

Organisation(s)
Computational and Soft Matter Physics
External organisation(s)
Universität Bayreuth
Journal
Physical Review E
Volume
108
No. of pages
12
ISSN
2470-0045
DOI
https://doi.org/10.1103/PhysRevE.108.054905
Publication date
11-2023
Peer reviewed
Yes
Austrian Fields of Science 2012
103029 Statistical physics, 103043 Computational physics
ASJC Scopus subject areas
Statistical and Nonlinear Physics, Statistics and Probability, Condensed Matter Physics
Portal url
https://ucrisportal.univie.ac.at/en/publications/f39592e5-ea1b-4849-8b4f-9d4e343e9320