Download Author Guidelines for 8 - ic-rmm1

Magnetorheology of the carbonyl iron/ZnO rod-like microparticle suspensions
Miroslav Mrlík1, 2, Michal Machovský1, 2 Vladimír Pavlínek1, 2, and Ivo Kuřitka1, 2
[email protected]
1Centre
of Polymer Systems, University Institute, Tomas Bata University in Zlin, Nad Ovcirnou
3685, 760 01 Zlin, Czech Republic
2Polymer Centre, Faculty of Technology, Tomas Bata University in Zlin, TGM 275, 762 72 Zlin,
Czech Republic
Magnetorheological (MR) suspensions are generally two-phase systems consisting of magnetic
particles and silicone oil. Upon application of an external magnetic field particles become magnetized
and form chain-like internal structures, resulting in the change of the rheological behaviour of whole
suspension. Viscosity can increase in several orders of magnitude and then return to its original value
when magnetic field is replaced. Thus, the viscosity of such suspensions can be controlled using
various magnetic field strengths. Reversible change of viscosity can find application in damping
systems or torque transducers.
This study is aimed on the prepraration of the novel magnetic particles assembled from carbonyl
iron (CI) core and ZnO rod-like shell. The hybrid CI/ZnO microparticles were prepared via two-step
synthesis. Firstly, the CI particles were seeded with ZnO crystal nuclei and further with the help of
hydrothermal synthesis the rod-like structures were formed. Prepared particles were characterized
using SEM technique as well as XRD analysis. Further, the magnetic properties of both bare CI
particles and CI/ZnO rod-like ones were investigated using vibration magnetization saturation method.
The rheological properties of the suspension consiting of bare CI and CI/ZnO rod-like were elucidated
in the absence as well as in the presence of the applied external magnetic fiedl strength. The
presented core-shell material based suspension exhibited similar MR efficiency in comparison to the
supesnsion based on bare CI particles. On the other hand, the thermal stabiliy of the particles was
considerably enhanced. Thus, the main aim of this contribution will be focused on the
magnetorheological behaviour of novel CI/ZnO rod-like particles, at broad temperature range.
Keywords: magnetorheology, carbonyl iron, ZnO rod-like particles, magnetic properties,
suspensions, rheological properties
Acknowledgement
The authors wish to thank the Grant Agency of the Czech Republic for the financial support of Grant
No. 202/09/1626.
This article was written with the support of the Operational Program Research and Development for
Innovations co-funded by the European Regional Development Fund (ERDF) and the national budget
of the Czech Republic, within the framework of project Centre of Polymer Systems (reg. number:
CZ.1.05/2.1.00/03.0111).
Please choose and underline: Invited (30 minutes), Oral (20 minutes) Short Oral (5 minutes +
poster) or Poster presentation do you like.