Project Status: finished
The sealing limit is one important limitation of the process window of sheet metal hydroforming. Necessary calibration pressure cannot be reached because of leakages if the blankholder force is too low. Avoiding these leakages by using special active fluid media like magnetorheological fluids can strongly increase the robustness of the forming process. The viscosity of these fluids increases with the applied magnetic field density, which leads to a decrease of leakage volume and an increase of the cavity pressure at the same time. The aim of this research project is to investigate wether the mentioned fluids can be used as a combined forming and sealing medium for forming processes and wether the selective application of magnetic fields in the flange area leads to a decrease of leakage rates. Thus the uncontrolled occurrence of leakages in hydroforming could be prevented.
Detailed view of the experimental setup and demonstrator parts formed at different cavity pressures
Rösel, S.; Merklein, M.; Grüner, M.:
Analytical and numerical approaches to predict the flow characteristics of a magnetorheological fluid in rotational symmetric cross sections.
In: Key Engineering Materials , 504-506(2012), Durnten-Zurich: Trans Tech Publications, pp. 399-404
Rösel, S.; Merklein, M.:
Flow behaviour of magnetorheological fluids, considering the challenge of sealing in blank hydroforming in the flange area with rectangular leakage area cross-sections.
In: Key Engineering Materials, 473(2011), Switzerland: Trans Tech Publications, pp. 121-129
Rösel, S.; Merklein, M.:
Enhancing Forming Limits by Using a Magnetorheological Fluid as Active Fluid Medium for Hydroforming.
In: Gerhard Hirt, A. Erman Tekkaya (Edt.): Steel research international: Special Edition: 10th International Conference on Technology of Plasticity, (2011), Weinheim: Wiley-VCH Verlag GmbH&Co. KGaA., pp. 453-458
Rösel, S.; Merklein, M.:
Characterization of a Magnetorheological Fluid with Respect to its Suitability for Hydroforming.
In: UNIVERSITY OF BRESCIA (Edt.): International Journal of Material Forming, 3(2010), Paris: Springer, pp. 283-286
Rösel, S.; Merklein, M.:
Characterization of a magnetorheological fluid and simulative design of a magnetic field with respect to its suitability for hydroforming.
In: Warsaw University of Technology, Faculty of Production Engineering (Edt.): Proceedings of the 5th International Conference on ADVANCES IN PRODUCTION ENGINEERING, (2010), Radom: Publishing and Printing House of the Institute for Sustainable Technologies, pp. 409-417
