Experiments on T-shape hydroforming with counter punch

In this study, a hydroforming test machine is designed and developed for tube hydroforming processes. This hydroforming test machine features four independent controls of two axial feeding punches, an internal pressure, and a counter punch. Using annealed AA6063-T5 and 6011A aluminum tubes, experiments of bulge forming and T-shape hydroforming are conducted. Loading paths and thickness distribution of the formed product are discussed. The branch heights of the formed products with and without the counter punch are compared to manifest the merit of using a counter punch during tube hydroforming.