Advertisement

Forming limit prediction of AA7075-T6 sheet based on ductile fracture criterion and the error analysis of parameters calibration

  • Zhuoyun Yang
  • Changcai Zhao
  • Guojiang DongEmail author
  • Zhiwei Chen
  • Yufei Sun
  • Xiangdong Jia
Original Research
  • 36 Downloads

Abstract

It is worthy to investigate how it will affect the parameters calibration using an average stress state variable before the practical application of a ductile fracture criterion. In order to study this problem, ten notch specimens of AA7075-T6 sheet were designed to implement the tension tests and a parallel simulation of each test was run to obtain the variation of related variables such as stress triaxiality, Lode parameter and fracture strain. The Lou-Huh criterion was selected to research the prediction error through the difference between the damage value calculated by integral expression and that calculated by analytical expression. Based on the error analysis method, a clear answer was given on how to choose the tension tests of notch specimens in the calibrating process of fracture parameters. The studying results show that the stress state variation of notch specimens has a significant influence on the calibration result. It turns out that how to choose specimens from the ten notch specimens to calibrate the fracture parameters also has big influence on the result. Therefore, it is necessary to conduct an error analysis after the calibration of fracture parameters. Based on the error analysis results, the fracture parameters of AA7075-T6 sheet were optimized and its forming limit diagram (FLD) was deduced based on the optimized parameters. The predictive result of FLD is safe compared with the experimental forming limit results.

Keywords

Ductile fracture criterion Error analysis Forming limit diagram AA7075-T6 sheet 

Notes

Acknowledgements

The present work is financed by the National Natural Science Foundation of China (contract no. 51775481), the Key Project of Science and Technology Plan of Hebei Higher School of Education Department (grant number ZD2017078) and the Natural Science Foundation of Hebei Province (project number E2019203418). The authors would like express their sincere appreciation to the funds.

Conflict of interest

We declare that no conflict of interest exits in the submission of this manuscript and manuscript is approved by all authors for publication. The work submitted was original research that has not been published previously and not under consideration for publication elsewhere, in whole or in part.

References

  1. 1.
    Hill R (1952) On discontinuous plastic states, with special reference to localized necking in thin sheets. J Mech Phys Solids 1:19–30MathSciNetCrossRefGoogle Scholar
  2. 2.
    Swift HW (1952) Plastic instability under plane stress. J Mech Phys Solids 1:1–18CrossRefGoogle Scholar
  3. 3.
    Marciniak Z, Kuczynski K (1967) Limit strains in the processes of stretch-forming sheet metal. Int J Mech Sci 9:609–620CrossRefGoogle Scholar
  4. 4.
    Lou Y, Huh H (2013) Prediction of ductile fracture for advanced high strength steel with a new criterion: experiments and simulation. J Mater Process Technol 213:1284–1302CrossRefGoogle Scholar
  5. 5.
    Zhuang X, Meng Y, Zhao Z (2017) Evaluation of prediction error resulting from using average state variables in the calibration of ductile fracture criterion. Int J Damage Mech 27:1231–1251CrossRefGoogle Scholar
  6. 6.
    McClintock FA (1968) A criterion for ductile fracture by the growth of holes. J Appl Mech-T ASME 35:363–371CrossRefGoogle Scholar
  7. 7.
    Rice JR, Tracey DM (1969) On the ductile enlargement of voids in triaxial stress fields. J Mech Phys Solids 17:201–217CrossRefGoogle Scholar
  8. 8.
    Cockcroft MG, Latham DJ (1968) Ductility and the workability of metals. J Inst Met 96:33–39Google Scholar
  9. 9.
    Brozzo P, Deluca B, Rendina R. A new method for the prediction of formability in metal sheets 1972. in: Proceedings of the 7th Biennial Conference of IDDRG on Sheet Metal Forming and FormabilityGoogle Scholar
  10. 10.
    Oh SI, Chen CC, Kobayashi S (1979) Ductile fracture in axisymmetric extrusion and drawing—part 2: workability in extrusion and drawing. J Eng Indust 101:36–44CrossRefGoogle Scholar
  11. 11.
    Oyane M, Sato T, Okimoto K, Shima S (1980) Criteria for ductile fracture and their applications. J Mech Work Technol 4:65–81CrossRefGoogle Scholar
  12. 12.
    Clift SE, Hartley P, Sturgess CEN, Rowe GW (1990) Fracture prediction in plastic deformation processes. Int J Mech Sci 32:1–17CrossRefGoogle Scholar
  13. 13.
    Han HN, Kim KA (2003) A ductile fracture criterion in sheet metal forming process. J Mater Process Technol 142:231–238CrossRefGoogle Scholar
  14. 14.
    Ozturk F, Lee D (2004) Analysis of forming limits using ductile fracture criteria. J Mater Process Technol 147:397–404CrossRefGoogle Scholar
  15. 15.
    Ko YK, Lee JS, Huh H, Kimet HK, Park SH (2007) Prediction of fracture in hub-hole expanding process using a new ductile fracture criterion. J Mater Process Technol 187:358–362CrossRefGoogle Scholar
  16. 16.
    Bao Y, Wierzbicki T (2004) On fracture locus in the equivalent strain and stress triaxiality space. Int J Mech Sci 46:81–98CrossRefGoogle Scholar
  17. 17.
    Lou Y, Huh H (2013) Extension of a shear-controlled ductile fracture model considering the stress triaxiality and the lode parameter. Int J Solids Struct 50:447–455CrossRefGoogle Scholar
  18. 18.
    Wierzbicki T, Bao Y, Lee Y, Bai Y (2005) Calibration and evaluation of seven fracture models. Int J Mech Sci 47:719–743CrossRefGoogle Scholar
  19. 19.
    Lou Y, Huh H, Lim SJ, Pack K (2012) New ductile fracture criterion for prediction of fracture forming limit diagrams of sheet metals. Int J Solids Struct 49:3605–3615CrossRefGoogle Scholar
  20. 20.
    Lou Y, Chen L, Clausmeyer T, Tekkayaet AE, Yoon JW (2017) Modeling of ductile fracture from shear to balanced biaxial tension for sheet metals. Int J Solids Struct 112:169–184CrossRefGoogle Scholar
  21. 21.
    Li H, Fu MW, Lu J, Yang H (2011) Ductile fracture: experiments and computations. Int J Plast 27(2):147–180CrossRefGoogle Scholar
  22. 22.
    Qian LY, Fang G, Zeng P, Wang Q (2015) Experimental and numerical investigations into the ductile fracture during the forming of flat-rolled 5083-O aluminum alloy sheet. J Mater Process Technol 220:264–275CrossRefGoogle Scholar
  23. 23.
    Gross AJ, Ravi-Chandar K (2016) On the deformation and failure of Al 6061-T6 at low triaxiality evaluated through in situ microscopy. Int J Fract 200(1–2):185–208CrossRefGoogle Scholar
  24. 24.
    Lou Y, Yoon JW, Huh H, Chao Q, Song J (2018) Correlation of the maximum shear stress with micro-mechanisms of ductile fracture for metals with high strength-to-weight ratio. Int J Mech Sci 146:583–601 CrossRefGoogle Scholar
  25. 25.
    Bai Y, Wierzbicki T (2008) A new model of metal plasticity and fracture with pressure and lode dependence. Int J Plast 24(6):1071–1096CrossRefGoogle Scholar
  26. 26.
    Cao J, Li F, Ma X, Sun Z (2018) A modified elliptical fracture criterion to predict fracture forming limit diagrams for sheet metals. J Mater Process Technol 252:116–127CrossRefGoogle Scholar

Copyright information

© Springer-Verlag France SAS, part of Springer Nature 2020

Authors and Affiliations

  1. 1.Key Laboratory of Advanced Forging & Stamping Technology and Science of Ministry of EducationYanshan UniversityQinhuangdaoChina
  2. 2.Hebei Key Laboratory of Special Delivery EquipmentYanshan UniversityQinhuangdaoChina
  3. 3.College of Mechanical and Electrical EngineeringNanjing Forestry UniversityNanjingChina

Personalised recommendations