Abstract: In the industrial field, tailored blank forming with aluminum alloy (Al-alloy) has developed fast to meet the demands for large size integrated components with curved surfaces of high precision and with uniform mechanical properties. Traditional forming methods for tailored blank components faced challenges with uneven deformation behaviors and coexistence of rupture and wrinkling defects occuring during the forming process. In this paper, a new manufacturing procedure is proposed with advanced welding and forming technologies for forming integrated shell components. Friction stir welding with post-weld heat treatment was employed to prepare the tailor welded blank and improve its formability prior to forming. A double-sided pressure sheet hydroforming process was introduced to fabricate the Al-alloy tailored blank into a curved surface shell. Finite element modeling was established to analyze the effect of the weld line position and loading paths of stress distributions during the double-sided sheet hydroforming (DSHF) process. A large double-action CNC sheet hydroforming press with tonnage of 150 MN and high pressure liquid volume of 5 m3  was developed in China. As an application case of the proposed process and equipment, a full-scale tank dome with a diameter of 3 m was successfully hydroformed with a large size Al-alloy tailored blank. It was shown that the DSHF process has the advantages in controlling rupture and wrinkling defects with an Al-alloy tailored blank, and the novel manufacturing procedure enables the production of integrated thin-walled component more competitively than traditional methods.

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