Analysis and design of hydroforming process for automobile rear axle housing by FEM

An FEM program, HydroFORM-3D, for the analysis and design of tube hydroform ing processes, has been developed by modifying and adding some subroutines to the previous rigid-plastic finite element program, and then applied to t he hydroforming process for an automobile rear axle housing. This paper inc ludes the theoretical background of the program development. Through a nume rical simulation, an optimum process is proposed to meet the practical requ irements, which shows the efficiency of the numerical simulation. Two types of hydroforming dies are analyzed by numerical simulation. The sliding-typ e die has the drawback of a possibility of buckling, whereas the fixed-type die causes bursting failure. The thickness distribution of the final produ ct is affected not only by the types of die, but also by the loading paths. The potential failure site for rear axle housing predicted by the numerica l simulation is consistent with the experimental results. The values of max imum axial compression force for the first and second hydroforming processe s are also in good agreement with experimental data; To manufacture a sound automobile rear axle housing without failure, it is better to use the slid ing-type die and it is also critical to maintain a suitable hydraulic press ure level. (C) 2000 Published by Elsevier Science Ltd.