Effects of punch size, magnetic field, and magnetorheological elastomers medium on forming T-shaped thin-walled Inconel 718 tubes

This study aims at investigating the impact of using the Magnetorheological Elastomers (MREs) medium to improve the formability of T-shaped Inconel 718 tubes during the bulging process. Besides, the influence of the punch size and the intensity of the magnetic field on the branch height and wall thickness distribution of the T-shaped Inconel 718 tubes are also explored. The results showed that the parts formed by the punch with a length of 5 mm in the pressurization zone have better forming quality. The external magnetic field can promote a high branch, and by increasing the intensity of the magnetic field, the branch height was increased and then decreased. At the same time, the magnetic field reduced the amount of material accumulation between the guiding zone and the bulging zone. Besides, it promotes the material in the guiding zone to enter the bulging zone and improve the bulging ability of the T-shaped tube.