Optimization of Initial Blank Shape for Minimizing the Trimming Process in Hot Stamping of T-Shaped Parts

  • Heung-Kyu Kim
  • Hyun-Bo Shim
  • Baeg-Soon Cha
  • Ga-Hyeong Song
  • Hyung-Jong Kim
Regular Paper
  • 1 Downloads

Abstract

Blank optimization in stamping is a way to reduce the cost of unnecessary material consumption or subsequent trimming operations by acquiring the final target part in a single forming process. There have been many studies on blank optimization in room temperature stamping, but few studies have yet been conducted in hot stamping. In this study, a blank shape optimization was conducted for a T-shaped part simulating a body center pillar. A finite element analysis (FEA) for the hot stamping process was performed using an appropriately assumed initial blank shape, and the blank shape was updated based on the shape error between the outline of the deformed blank obtained from the FEA and that of the target part. The shape error was calculated by applying the modified radius vector method. Hot stamping test was carried out using the optimal shaped blank predicted by the FEA. It was confirmed that the outline of the deformed blank obtained by the actual test was very close to the outline of the target part. From the results of this study, it can be seen that the blank optimum design technique at room temperature stamping can be applied to the case in hot stamping.

Keywords

Optimal blank design Hot stamping T-shaped part Die quenching Finite element analysis 

Nomenclature

Xm

position vector of the node ‘m’ located at the boundary of the blank before deformation

xm

position vector of the node ‘m’ located at the boundary of the blank after final deformation.

\({x_T}^P\)

position vector of the point ‘p’ located at the contour of the target shape

Nm

inward unit normal vector to the contour at the node ‘m’

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Vogel, J. H. and Lee, D., “An Analysis Method for Deep Drawing Process Design,” International Journal of Mechanical Sciences, vol. 32, no. 11, pp. 891–907, 1990.CrossRefGoogle Scholar
  2. 2.
    Sowerby, R., Duncan, J., and Chu, E., “The Modelling of Sheet Metal Stampings,” International Journal of Mechanical Sciences, vol. 28, no. 7, pp. 415–430, 1986.CrossRefGoogle Scholar
  3. 3.
    Lee, C. H. and Huh, H., “Blank Design and Strain Prediction of Automobile Stamping Parts by an Inverse Finite Element Approach,” Journal of Materials Processing Technology, vol. 63, Nos. 1–3, pp. 645–650, 1997.CrossRefGoogle Scholar
  4. 4.
    Barlat, F., Chung, K., and Richmond, O., “Anisotropic Plastic Potentials for Polycrystals and Application to the Design of Optimum Blank Shapes in Sheet Forming,” Metallurgical and Materials Transactions A, vol. 25, no. 6, pp. 1209–1216, 1994.CrossRefGoogle Scholar
  5. 5.
    Kim, S., Park, M., Kim, S., and Seo, D., “Blank Design and Formability for Non-Circular Deep Drawing Processes by the Finite-Element Method,” Journal of Materials Processing Technology, vol. 75, Nos. 1–3, pp. 94–99, 1998.CrossRefGoogle Scholar
  6. 6.
    Shim, H. B. and Son, K. C., “Optimal Blank Design for the Drawings of Arbitrary Shapes by the Sensitivity Method,” Journal of Engineering Materials and Technology, vol. 123, no. 4, pp. 468–475, 2001.CrossRefGoogle Scholar
  7. 7.
    Son, K. and Shim, H., “Optimal Blank Shape Design Using the Initial Velocity of Boundary Nodes,” Journal of Materials Processing Technology, vol. 134, no. 1, pp. 92–98, 2003.CrossRefGoogle Scholar
  8. 8.
    Shim, H. B., “Determination of Optimal Blank Shape by the Radius Vector of Boundary Nodes,” Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture, vol. 218, no. 9, pp. 1099–1111, 2004.CrossRefGoogle Scholar
  9. 9.
    Scientific Forming Technologies Corporation, “DEFORM-3D,” https://www.deform.com/products/deform-3d/(Accessed 9 APR 2018)Google Scholar
  10. 10.
    Sente Software Ltd., “JMatPro,” https://www.sentesoftware.co.uk/jmatpro (Accessed 9 APR 2018)Google Scholar
  11. 11.
    Avrami, M., “Kinetics of Phase Change. I General Theory,” The Journal of Chemical Physics, vol. 7, no. 12, pp. 1103–1112, 1939.CrossRefGoogle Scholar
  12. 12.
    Avrami, M., “Kinetics of Phase Change. II Transformation-Time Relations for Random Distribution of Nuclei,” The Journal of Chemical Physics, vol. 8, no. 2, pp. 212–224, 1940.CrossRefGoogle Scholar
  13. 13.
    Avrami, M., “Granulation, Phase Change, and Microstructure Kinetics of Phase Change. III,” The Journal of Chemical Physics, vol. 9, no. 2, pp. 177–184, 1941.CrossRefGoogle Scholar
  14. 14.
    Johnson, W. A. and Mehl, R. F., “Reaction Kinetics in Processes of Nucleation and Growth,” Transactions of the Metallurgical Society of AIME, vol. 135, pp. 416–442, 1939.Google Scholar
  15. 15.
    Kolmogorov, A. N., “On the Statistical Theory of the Crystallization of Metals,” Bulletin of the Academy of Sciences of the USSR, Mathematics Series, vol. 1, pp. 355–359, 1937.Google Scholar
  16. 16.
    Koistinen, D. and Marburger, R., “A General Equation Prescribing the Extent of the Austenite-Martensite Transformation in Pure Iron-Carbon Alloys and Plain Carbon Steels,” Acta Metallurgica, vol. 7, no. 1, pp. 59–60, 1959.CrossRefGoogle Scholar
  17. 17.
    Fahiminia, M., Naserian, M. M., Goshayeshi, H. R., and Majidian, D., “Investigation of Natural Convection Heat Transfer Coefficient on Extended Vertical Base Plates,” Energy and Power Engineering, vol. 3, no. 2, pp. 174–180, 2011.CrossRefGoogle Scholar
  18. 18.
    Hireholi, S., Shashishekhar, K., and Milton, S. G., “Experimental Determination of Heat Transfer Coefficient by Natural Convection for a Commercially Available Heat Sink Used for Cooling of Electronic Chips,” International Journal of Mechanical and Industrial Engineering, vol. 3, no. 1, pp. 43–45, 2013.Google Scholar
  19. 19.
    Kim, H.-K., Lee, S. H., and Choi, H., “Evaluation of Contact Heat Transfer Coefficient and Phase Transformation during Hot Stamping of a Hat-Type Part,” Materials, vol. 8, no. 4, pp. 2030–2042, 2015.CrossRefGoogle Scholar
  20. 20.
    Shim, H. B., “Measurement of Shape Error for the Optimal Blank Design of Stamped Part with 3 Dimensional Contour Lines,” International Journal of Precision Engineering and Manufacturing, vol. 16, no. 13, pp. 2665–2672, 2015.CrossRefGoogle Scholar

Copyright information

© Korean Society for Precision Engineering and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Automotive EngineeringKookmin UniversitySeoulRepublic of Korea
  2. 2.Department of Mechanical EngineeringYeungnam UniversityGyeongsangbuk-doRepublic of Korea
  3. 3.Molds & Dies R&D GroupKorea Institute of Industrial TechnologyIncheonRepublic of Korea
  4. 4.Department of Mechanical and Biomedical EngineeringKangwon National UniversityKoreaRepublic of Korea

Personalised recommendations