Research on influencing factors and laws of free-bending forming limit of tube

  • Wenbin Wei
  • Hui Wang
  • Hao Xiong
  • Xuan Cheng
  • Jie Tao
  • Xunzhong GuoEmail author


For the free-bending forming of complex bending components, the forming limit significantly influences the complexity of the forming materials. In this study, the wrinkle factor Iw, which comprehensively affects the forming limit of free-bending, was obtained by theoretical analysis. The process parameters affecting the forming limit of free-bending were systematically studied by using the ABAQUS finite element simulation platform. Moreover, the effects of series of parameters on the relationship curve and wrinkling factor under different eccentricity conditions were also analyzed. The free-bending forming limit under the optimal conditions was obtained, which provides a process optimization method to improve the forming limit for practical test and production. Furthermore, the forming experiments were conducted on tubes with different wall thickness, and it was verified that the wall thickness factors significantly influenced the forming limit of the tubes. Finally, the forming experiments were carried out on 6061-T6 aluminum alloy, H2 copper, and H62 brass tubes. The results proved that the yield strength was the key material parameter affecting the forming limit of metal tubes.


Free-bending Forming limit Wrinkle factor Process parameters Material parameter 


Funding information

The authors greatly acknowledge the financial support from the National Natural Science Foundation International (regional) cooperation and exchange project (Grant No.51711540301), the National Natural Science Foundation of China (Grand No. 51875548), “the Fundamental Research Funds for the Central Universities”(No. kfjj20180612), the Open Research Funds for the Jiangsu Key Laboratory of Nuclear Energy Equipment Materials Engineering (No. NJ20170012), and the China Aviation Science Foundation (No. 2016ZE52047).


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Copyright information

© Springer-Verlag London Ltd., part of Springer Nature 2019

Authors and Affiliations

  • Wenbin Wei
    • 1
    • 2
  • Hui Wang
    • 2
    • 3
  • Hao Xiong
    • 1
    • 2
  • Xuan Cheng
    • 1
    • 2
  • Jie Tao
    • 1
    • 2
  • Xunzhong Guo
    • 1
    • 2
    Email author
  1. 1.College of Material Science and TechnologyNanjing University of Aeronautics and AstronauticsNanjingPeople’s Republic of China
  2. 2.Jiangsu Key Laboratory of Nuclear Energy Equipment Materials EngineeringNanjing University of Aeronautics and AstronauticsNanjingPeople’s Republic of China
  3. 3.College of Mechanical and Electrical EngineeringNanjing University of Aeronautics and AstronauticsNanjingPeople’s Republic of China

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