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

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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.

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Correspondence to Xunzhong Guo.

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Wei, W., Wang, H., Xiong, H. et al. Research on influencing factors and laws of free-bending forming limit of tube. Int J Adv Manuf Technol 106, 1421–1430 (2020) doi:10.1007/s00170-019-04692-0

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  • Free-bending
  • Forming limit
  • Wrinkle factor
  • Process parameters
  • Material parameter