Transactions of Materials Processing (소성∙가공)

The Korean Society for Technology of Plasticity and materials processing (한국소성∙가공학회)
권호 표지
DOI QR코드

DOI QR Code

Study on the Deformation Characteristics of AZ31B Sheets in V-bending and Effect of Bottoming Process

마그네슘 합금 판재의 온간 V-굽힘에서 소재의 변형 및 보토밍 공정의 효과 분석

  • Kim, H.W. ;
  • Yu, J.H. ;
  • Lee, C.W. (Department of Mechanical system and Design Engineering, Seoul National University of Science and Technology)
  • 김현우 (서울과학기술대학교 기계디자인금형공학과) ;
  • 유제형 (서울과학기술대학교 기계디자인금형공학과) ;
  • 이창환
  • Received : 2018.01.08
  • Accepted : 2018.05.15
  • Published : 2018.06.01
Download PDF
⟨ Previous Next ⟩

Abstract

Many studies have been conducted on the process of forming magnesium alloy sheets to reduce the body weights of vehicles. Magnesium has a lower specific gravity than steel and also has a higher specific strength. Mg alloy sheets have low formability and a lot of springback due to their limited ductility and low young's modulus. As the temperature increases, the yield strength of the material decreases. Warm forming increases the formability and minimizes the springback of a material by heating it and the die to reduce the required load at forming. In this study, the temperature of the AZ31B sheet was controlled in order to reduce springback and increase formability. However, as the temperature increased, the deformation characteristics of the material changed and the radius of curvature of the material increased. The load and springback amount required for forming were analyzed according to the temperature and the bottoming force in the bending deformation.

Keywords

References

  1. L. Wang, G. Huang, H. Zang, Y. Wang, L. Yin, 2013, Evolution of springback and neutral layer of AZ31B magnesium alloy V-bending under warm forming conditions, J. Mater. Process. Technol., Vol. 213, No. 6, pp. 844-850. https://doi.org/10.1016/j.jmatprotec.2013.01.005
  2. C. Bruni, A. Forcelles, F. Gabrielli, M. simoncini, 2006, Air bending of AZ31 magnesium alloy in warm and hot forming conditions, J. Mater. Process. Technol., Vol 177, No.1-3, pp. 373-376. https://doi.org/10.1016/j.jmatprotec.2006.03.222
  3. T. Hama, Y. Kariyazaki, K. Ochi, H. Fujimoto, H.Takuda, 2010, Springback Characteristics of Magnesium Alloy Sheet AZ31B in Draw-Bending, J. Jpn. Soc. Technol. Plast. Vol. 51, No. 4, pp. 685-693. https://doi.org/10.9773/sosei.51.685
  4. D.T Nguyen, S.H. Yang, D.W. Jung, T.L Banh, Y. S Kim, 2012, A study on material modeling to predict spring-back in V-bending of AZ31 magnesium alloy sheet at various temperatures, Int. J. Adv. Manuf. Technol., Vol 62, No 5-8, pp.551-562. https://doi.org/10.1007/s00170-011-3828-y
  5. N.T. Nguyen, O.S. Seo, C.A. Lee, M.G Lee, J.H Kim, H.Y. Kim, 2014, Mechanical Behavior of AZ31B Mg Alloy Sheets under Monotonic and Cyclic Loadings at Room and Moderately Elevated Temperature, Mater., Vol 7, No 2, pp 1271-1295. https://doi.org/10.3390/ma7021271
  6. D.G. Jung, H.K. Kim, 2010, A study on magnesium alloy sheet springback caused by warm press forming process, fall meeting of KSPE, pp.871-872
  7. E.H. Lee, J.W. Yoon, D.Y. Yang, 2017, Study on springback from thermal-mechanical boundary condition imposed to V-bending and L-bending processes coupled with infrared rays local heating, Int. J. Mater. Form., DOI:10.1007/s12289-017-1375-2, pp.1-17.
  8. E.H. Lee, J.S. Hwang, C.W. Lee, D.Y. Yang, 2014, The Effect of Temperature on Springback of AZ31, Ti-GR2 during V-bending with Focused Heating using Near-infrared Radiation, Trans. Mater. Process., Vol. 23, No. 8, pp. 469-474. https://doi.org/10.5228/KSTP.2014.23.8.469
  9. Y.Q. Cheng, H. Zhang, Z.H. Chen, K.F. Xian, 2008, Flow stress equation of AZ31 magnesium alloy sheet during warm tensile deformation, J. Mater. Process. Technol., Vol. 208, No. 1-3, pp. 29-34. https://doi.org/10.1016/j.jmatprotec.2007.12.095
  10. C.A. Lee, M.G. Lee, O.S. Seo, N.T. Nguyen, J.H. Kim, H.Y. Kim, 2015, Cyclic behavior of AZ31B Mg: Experiments and non-isothermal forming simulations, Int. J. Plast., Vol. 75, pp. 39-62. https://doi.org/10.1016/j.ijplas.2015.06.005