The effect of tube bending, heat treatment and loading paths on process responses of hydroforming for automobile intercooler pipe: numerical and experimental investigations

This study was carried out to investigate the effect of preliminary processes on tube hydroforming (THF) and to optimize the THF process parameters to achieve a sound complex 3D curved intercooler pipe without failure by numerical and experimental approaches. The effect of three-step rotary bending on the thickness distribution and microstructure of the tube has been evaluated. The necessity of heat treatment is analyzed prior to the THF process. The stroke of punches should be optimized separately according to the asymmetry geometry characteristics of the intercooler pipe. The suitable loading path is discussed during the THF process. The results obtained from simulation keep a reasonable agreement with that from the experiment.