Investigation of factors which cause breakage during the hydroforming of an automotive part

Abstract Tube hydroforming is receiving an increasing amount of attention, due to the increased interest in the preservation of the global environment and demand for impact-damage resistance for automobile body-structures. Knowledge of the process is, however, still insufficient to produce high-quality products in an efficient way. In the research reported in this paper, an automotive part formed with multistage processes was analyzed with an elastoplastic finite element method (FEM) code which was developed with a static explicit method. The computed distributions of the thickness strain were compared with the experimental results. Good agreement was obtained, which confirmed the validity of the code. Further analysis revealed that the weld line of a tube is crucial for tube hydroforming simulation, especially for the strain distribution. Subsequently, factors which cause the breakage on the inside of the bent portion of the product were investigated, which referred to both deformation processes and strain paths. This investigation clarified factors which cause the breakage of the product.

[1]  Jeong Kim,et al.  Analysis and design of hydroforming process for automobile rear axle housing by FEM , 2000 .

[2]  B. J. Mac Donald,et al.  Finite element simulation of bulge forming of a cross-joint from a tubular blank , 2000 .

[3]  Soo-Ik Oh,et al.  The tube bending technology of a hydroforming process for an automotive part , 2001 .

[4]  B Carleer,et al.  Analysis of the effect of material properties on the hydroforming process of tubes , 2000 .

[5]  Taylan Altan,et al.  Tube hydroforming: state-of-the-art and future trends , 2000 .

[6]  James R. Rice,et al.  Localized necking in thin sheets , 1975 .

[7]  F. Dohmann,et al.  Tube hydroforming—research and practical application , 1997 .

[8]  Huilin Xing,et al.  Numerical analysis and design for tubular hydroforming , 2001 .

[9]  Mustafa A. Ahmetoglu,et al.  Tube hydroforming: current research, applications and need for training , 2000 .

[10]  J. Rice,et al.  Finite-element formulations for problems of large elastic-plastic deformation , 1975 .

[11]  Y. Yamada,et al.  Plastic stress-strain matrix and its application for the solution of elastic-plastic problems by the finite element method , 1968 .

[12]  Taylan Altan,et al.  The use of FEA and design of experiments to establish design guidelines for simple hydroformed parts , 2000 .

[13]  Taylan Altan,et al.  An overall review of the tube hydroforming (THF) technology , 2001 .

[14]  A. Makinouchi,et al.  Shell-element formulation in the static explicit FEM code for the simulation of sheet stamping , 1995 .

[15]  R. Hill.  A theory of the yielding and plastic flow of anisotropic metals , 1948, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.