This paper deals with the optimization of tube hydroforming parameters in order to reduce defects that may occur at the end of the forming process such as necking and wrinkling. A specific methodology is proposed based on the coupling between an inverse finite element model for the rapid simulation of the tube hydroforming process, and a response surface method based on diffuse approximation. The response surfaces are built using moving least-squares approximations and constructed within a moving region of interest, which moves across a predefined discrete grid of authorized experimental designs. An application of hydroforming of a bulge from aluminium alloy 6061-T6 tubing has been utilized to validate the methodology. The final design is validated with ABAQUS Explicit Dynamic commercial code.

No abstract

No abstract

No abstract

In tube hydroforming (THF) the optimal thickness variation of a product is influenced by the geometrical, material and process parameters. In this study different values of initial tube length combined with various fillet and entry radii of the die are taken into account to predict an acceptable T-shaped tube of which the minimum wall thickness fulfills the industrial demand. To reach this goal, an integrated optimization approach, using the classical explicit dynamic (ED) incremental approach using ABAQUS ® commercial code together with an optimization algorithm was developed. This latter consists in constructing an explicit form of the objective function by response surface methodology (RSM) based on diffuse approximation (DA) according to the design variables. To search the global optimum of the objective function, the sequential quadratic programming (SQP) algorithm has been used.