Rigid–plastic finite element analysis of hydroforming process and its applications

An finite element method (FEM) program, HydroFORM-3D, for the analysis and design of tube hydroforming processes, has been developed, and then applied to the hydroforming process for an automobile rear axle housing and subframe. This paper includes the theoretical background of the program. By using the developed program and the ductile fracture criterion, the process design for the straight tube hydroforming process of a rear axle housing, is presented. The potential failure site for the rear axle housing predicted by the numerical simulation is consistent with experimental results. The preform design of the typical pre-bent tube hydroforming process of forming a subframe, which concentrates on the determination of initial diameter of the tubular blank, is suggested.