Thickness prediction of sheet hydroforming FEM simulation with movable die approach Response Surface Method

In this paper, the hydroforming process with a movable mold was analyzed by elastoplastic FEM1. The effects of various process parameters on the deformation of the sheet blanks were investigated. The forming conditions affecting thinning degree have been analyzed. Design of experiments has been used to study the effects of the main hydroforming parameters such as the retreat speed of movable mold, the movable mold radius, and the amount of friction coefficient between blank and movable mold surface.The effect of these parameters on the final thickness of blank center has been investigated using response surface methodology (RSM). Response surface contours were constructed for determining the optimum forming conditions for a required thickness. The final blank thickness was found to increase with increase in the friction and it decreased with decrease in the amount of the retreat speed of movable mold used