Preform design in hydroforming of automobile lower arm by FEM

By using a three-dimensional finite element program HydroFORM-3D based on a rigid–plastic model, the hydroforming process for automobile lower arm is analyzed in this study. The goal of the study is to accomplish proper design and control of processes for producing hydroformed lower arm component most soundly. Prior to hydroforming, the tube must be bent to the approximate centerline of the finished part to enable the tube to be placed in the die cavity. After then, a preforming operation is carried out to the pre-bent tube. Finally, the hydroforming operation is performed to the preformed tube to get the final production. The influences of forming conditions, such as the loading path of the hydraulic pressure and the axial feeding, on the hydroforming process is discussed.