An adaptive simulation approach designed for tube hydroforming processes

The efficiency of a tube hydroforming process is largely dependent on the process control parameters (i.e. the internal pressure and the axial feeding) since they determine the occurrence of forming limits such as wrinkling and bursting. Therefore, these parameters should be carefully selected. In this paper an adaptive method is presented to obtain a more efficient process control for tube hydroforming processes. This method avoids the onset of wrinkling and bursting via dedicated stability criteria. The wrinkling criterion uses an energy-based indicator inspired on the plastic bifurcation theory. For necking, followed by bursting, a criterion based on the forming limit curve is employed. Applying these two criteria, the process parameters are adjusted during the simulation via a fuzzy knowledge based controller (FKBC). A case study is carried out for the hydroforming of a T-shape part using the designed adaptive system in combination with the finite element method. For the simulations ABAQUS/Explicit is used.