Parts | Days | Selection | Search | Downloads | Help
DY: Fachverband Dynamik und Statistische Physik
DY 30: Poster II
DY 30.63: Poster
Thursday, March 29, 2007, 16:00–18:00, Poster D
Experimental realisation of the Rosensweig instability with ferrogels — •Christian Gollwitzer1, Marina Krekhova2, Ingo Rehberg1, Günter Lattermann2, and Reinhard Richter1 — 1Experimentalphysik V, Universität Bayreuth — 2Makromolekulare Chemie I, Universität Bayreuth
Ferrogels are an interesting new class of materials that enhance the properties of magnetic fluids by elastic components [1]. The most striking phenomenon in ferrofluids, namely the Rosensweig instability, shows also up in ferrogels under certain conditions. Bohlius et al. [2] predict, that compared to the pure ferrofluid, the critical magnetic field is shifted to higher values due to elastic forces, and the critical wavenumber to remain the same.
We use a thermoreversible ferrogel [3] and expose it to a homogeneous magnetic field. By controlling the temperature we can easily change the elastic modulus over several orders of magnitude. The surface profile of the ferrogel is then recorded using an X-ray technique.
[1] Zrinyi, M., Barsi, L., Szabo, D. & Kilian, H.-G. 1997
The Journal of Chemical Physics 106 (13), 5685–5692.
[2]Bohlius, Brand & Pleiner 2006 Z. Phys. Chem
220, 97
[3]Lattermann, G. & Krekhova, M. 2006 Macromol. Rapid Commun. 27, 1373–1379.