Improving formability due to an enhancement of sealing limits caused by using a smart fluid as active fluid medium for hydroforming

Within this paper a new approach to enhance the process window in sheet metal hydroforming processes will be presented. The key idea of the technology is the local adaption of the properties of the active fluid medium. In this case the magnetorheological fluid (MRF) Basonetic (R) 5030 is used and the fluid behavior is changed due to a partially applied external magnetic field. Based on the new property distribution the medium can be used as forming and sealing medium at the same time. The results are compared to the values reached with mineral oil. The presented work covers all necessary steps for a successful application of the technology. After the presentation of the used fluids, a material characterization and the tools, which are developed for this reason, as the sealing limits for two different configurations are determined. Based on these investigations forming operations are carried out at the related process parameters to show up the potential of the MRF. At the end a numerical model is built up and validated for both fluids used to offer a qualified tool for process design.