Tooling design in sheet metal forming using springback calculations

Abstract A method to design tooling in sheet metal forming using springback calculations is presented. The designed tooling produces a part which matches the desired shape, thereby compensating for springback. To design the appropriate tooling, traction distributions on the sheet in the fully loaded deformed state are computed using the finite element method. The calculated tractions are then used to numerically reproduce springback of the desired part shape by elastic unloading of the part in a reverse manner. The method is examined for materials covering a range of steel strength and hardening, and is found to produce parts with negligible shape error. The success of the tooling design algorithm leads to a proposal for an experimental method to design tooling based on traction distribution measurements.

[1]  Robert A. Ayres,et al.  SHAPESET: A process to reduce sidewall curl springback in high-strength steel rails , 1984 .

[2]  H. D. Hibbitt,et al.  Finite element analysis of sheet forming processes , 1990 .

[3]  Yuji Umehara,et al.  Technologies for the more precise press-forming of automobile parts , 1990 .

[4]  S. Ramalingam,et al.  Piezoelectric thin film stress sensors for metal-forming operations , 1989, Proceedings., IEEE Ultrasonics Symposium,.

[5]  Tongxi Yu,et al.  Springback after the biaxial elastic-plastic pure bending of a rectangular plate—I , 1981 .

[6]  David E. Hardt,et al.  Closed Loop Control of a Roll Straightening Process , 1984 .

[7]  Yasuhisa Tozawa,et al.  Forming technology for raising the accuracy of sheet-formed products , 1990 .

[8]  M. Domroese,et al.  Real-Time Control of Twist Deformation , 1987 .

[9]  Y. Liu,et al.  The Effect of Restraining Force on Shape Deviations in Flanged Channels , 1988 .

[10]  David E. Hardt,et al.  A Transfer Function Description of Sheet Metal Forming for Process Control , 1991 .

[11]  David C. Gossard,et al.  An Adaptive Pressbrake Control Using an Elastic-Plastic Material Model , 1982 .

[12]  David E. Hardt,et al.  Sheet Metal Die Forming Using Closed-Loop Shape Control , 1982 .

[13]  Tongxi Yu,et al.  On the range of applicability of results for the springback of an elastic/perfectly plastic rectangular plate after subjecting it to biaxial pure bending—II , 1981 .

[14]  Kim A. Stelson,et al.  Finite Element Method for the Analysis of a Material Property Identification Algorithm for Pressbrake Bending , 1988 .

[15]  Mary C. Boyce,et al.  Finite Element Analyses of Real-Time Stability Control in Sheet Forming Processes , 1992 .