Finite element simulation on superplastic blow forming of diffusion bonded 4 sheets

Superplastic blow forming process using diffusion bonded multi-sheets is an effective forming technology for production of multi-cell structures which should have light weight and high stiffness for aerospace applications. In the current study, finite element analysis of the superplastic blow forming process has been carried out in order to investigate the effect of optimal strain rate and pressure limit on sink mark formation, which often occurs in the blow forming process of diffusion, bonded multi-sheets. The simulation was focused on the deformed shape of the sheets. The forming pressure profile obtained from the simulation was employed in the production of the prototype, and the simulation result was compared with the experiment in terms of the final shape.