This paper studies the effects of some modeling parameters on the accuracy of finite element simulation in sheet-metal forming. A simple stepdie, which simulates binder forming, is used. In this two-dimensional case, a flat blank is bent into an S-shape, which has an exact solution. Four modeling parameters are studied. They are: die close speed, die gap, mass damping, and width of blank. One significant finding of this study reveals that in calculations using explicit finite elements, the simulation speed should be selected with care. The dynamic effects may be prevalent if the simulation speed is too fast. Numerical errors may accumulate and renders the results erroneous if it is too slow.

Issue Section:
Technical Papers
Keywords:
modelling, digital simulation, finite element analysis, forming processes, metalworking
Topics:
Binders (Materials), Blanks, Damping, Finite element analysis, Modeling, Shapes, Simulation, Oscillations, Errors, Simulation results
1.
Mattiasson, K., Samuelsson, A., Wood, R. D., and Zienkiewicz, O. C., 1986, NUMIFORM’86 Numerical Methods in Industrial Forming Processes, A. A. Balkema, Rotterdam.
2.
Wu, L., 1993, “Application of dynamic relaxation method to the prediction of springback and residual stress in sheet metal forming,” Computer Applications in Shaping & Forming of Materials, M. Y. Demeri, ed., The Minerals, Metals and Materials Society.
3.
Chung, W. J., Cho, J. W., and Belytschko, T., 1996, “A study on dynamic effects of dynamic explicit FEM in sheet metal forming analysis,” NUMISHEET’96, pp. 414–420.
4.
Shen, S. F., and Dawson, P. R., 1995, NUMIFORM’95 Simulation of Material Processing: Theory, Methods and Applications, A. A. Balkema, Rotterdam.
5.
Stevenson, R., 1988, “Development in the design and analysis of sheet metal forming dies,” Product and Process Design, ASME H00412, pp. 173–179.
6.
Chen, K. K. and Campbell, M. P., 1994, “Using a geometric toolkit to link finite element calculations in sheet metal forming analysis,” SAE paper #940748, SAE Publication SP-1021, pp. 1–10.
7.
Chen, K. K., 1987, “A new finite element method for binder wrap calculations,” J. Materials Shaping Technology, pp. 107–116.
8.
Tang, S. C., 1985, “Verification and application of a binder wrap analysis,” Computer Modeling of Sheet Metal Forming Process, N. M. Wang and S. C. Tang, eds., The Metallurgical Society, pp. 193–208.
9.
Chen, K. K. and Sun, P. C. 1995, “Evaluation of a dynamic explicit finite element code for binder forming calculations,” SAE paper #950693, SAE Publication SP-1067, pp. 19–26.
Copyright © 2001
 by ASME
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