Eliminating springback error in U-shaped part forming by variable blankholder force

  • Gang Liu
  • Zhongqin Lin
  • Youxia Bao
  • J. Cao
Article

Abstract

Springback is the main concern in U-shaped part forming, which would adversely affect desired part geometries. The use of variable blankholder force in the forming process is one effective method to reduce springback. However, there has not been a systematic way to determine the blankholder force trajectory. In this article, a methodology of obtaining this blankholder force trajectory in forming a U-shaped part that considers the wrinkling limit and fracture limit in the forming process was proposed. The method was validated numerically by using the Finite Element Method to simulate the benchmark of a 2-D draw bending problem in NUMISHEET’93. With the calculated blankholder force trajectory, higher forming quality was obtained and compared with constant blankholder force cases. Springback was kept at a minimum while avoiding cracking.

Keywords

sheet metal forming springback U-shaped part variable blankholder force 

References

  1. 1.
    Y.Y. Yang: Complicated Sheet Metal Forming Technology, National Defense Publication, Piking, 1996, pp. 106–7.Google Scholar
  2. 2.
    M. Kawka, A. Makinouchi, and S.P. Wang: “Simulating Manufacturing Processes,” Automotive Engineering, 1997, 105(4), pp. 31–33.Google Scholar
  3. 3.
    K. Kazama, T. Nukaga, and H. Makino: “Springback Simulation of Truck’s Frame Side Member” in Proceedings of NUMISHEET’99, J.C. Gelin and P. Picart, ed., University of the Franche-Comte and ENSMM Besancon, 1999, pp. 65–70.Google Scholar
  4. 4.
    Y.C. Liu: “The Effect of Restraining Force on Shape Deviation in Flanged Channels.” J. Eng. Mater. Technol., 1988, 110, pp. 389–94.CrossRefGoogle Scholar
  5. 5.
    D. Schmockel and M. Beth: “Springback Reduction in Draw Bending Process of Sheet Metals.” Annals of the CIRP, 1993, 42(1), pp. 339–42.CrossRefGoogle Scholar
  6. 6.
    M. Sunseri, J. Cao, and A.P. Karafillis: “Accommodation of Springback Error in Channel Forming Using Active Blankholder Force Control: Numerical Simulations and Experiments.” J. Eng. Mater. Technol., 1996, 118(3), pp. 426–35.Google Scholar
  7. 7.
    R. Ruffini and J. Cao: “Using Neural Network for Springback Minimization in a Channel Forming Process.” Proceedings of the 1998 SAE International Congress & Exposition, 1998, pp. 77–85.Google Scholar
  8. 8.
    B. Kinsey, J. Cao, and S. Solla: “Consistent and Minimal Springback Using a Stepped Blankholder Force Trajectory and Neural Network Control.” J. Eng. Mater. Technol., 2000, 122, pp. 113–18.CrossRefGoogle Scholar

Copyright information

© ASM International 2002

Authors and Affiliations

  • Gang Liu
    • 1
  • Zhongqin Lin
    • 1
  • Youxia Bao
    • 1
  • J. Cao
    • 2
  1. 1.School of Mechanical EngineeringShanghai Jiaotong UniversityShanghaiPeople’s Republic of China
  2. 2.Department of Mechanical EngineeringNorthwestern UniversityEvanston

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