Effects of sheet thickness and anisotropy on forming limit curves of AA2024-T4

  • Murat Dilmec
  • H. Selcuk Halkaci
  • Fahrettin Ozturk
  • Haydar Livatyali
  • Osman Yigit


In this study, the effects of sheet thickness and anisotropy of AA2024-T4 on forming limit curve (FLC) are experimentally investigated according to ISO 12004-2 standard. A new limit strain measurement method is proposed by using the grid analysis method so as to determine limit strains conveniently and reliably. In addition to the regular test specimens, various widths are added to enhance the FLC’s accuracy at the plane strain condition (PSC). The accuracy and reliability of the proposed method are verified for different materials. Results illustrate that an increase in the sheet thickness increases the FLC level. The additional experiments for additional widths improve the accuracy of the FLC at the PSC, and the position of the lowest major strain value differs from the literature. However, the effect of anisotropy on the FLC is found to be insignificant. Finally, experimental and numerical case studies are carried out for conventional deep drawing, stretch drawing, and hydraulic bulge processes. Results reveal that different FLCs are necessary for different thicknesses for accurate predictions.


Forming limit curve AA2024 Thickness effect Anisotropy effect 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Emilie H, Carsley JE, Verma R (2008) Development of forming limit diagrams of aluminum and magnesium sheet alloys at elevated temperatures. J Mater Eng Perform 17:288–296CrossRefGoogle Scholar
  2. 2.
    Paraianu L, Comsa DS, Gracio JJ, Banabic D (2005) Modelling of the forming limit diagrams using the finite element method. The 8th International Conference of the European Scientific Association for Material Forming ESAFORMGoogle Scholar
  3. 3.
    Derogar A, Djavanroodi F (2011) Artificial neural network modeling of forming limit diagram. Mater Manuf Process 26:1415–1422CrossRefGoogle Scholar
  4. 4.
    Narayanan RG, Naik BS (2010) Assessing the validity of original and modified failure criteria to predict the forming limit of unwelded and tailor welded blanks with longitudinal weld. Mater Manuf Process 25:1351–1358CrossRefGoogle Scholar
  5. 5.
    Narayanasamy R, Narayanan SC (2007) Experimental analysis and evaluation of forming limit diagram for interstitial free steels. Mater Des 28:1490–1512CrossRefGoogle Scholar
  6. 6.
    Giuliano G (2006) Analysis of forming limit diagram for superplastic materials. Int J Adv Manuf Technol 31(3–4):244–246CrossRefGoogle Scholar
  7. 7.
    Hosford WF, Caddell R (2007) Metal forming: mechanics and metallurgy, 3rd edn. Cambridge University Press, New YorkCrossRefGoogle Scholar
  8. 8.
    Graf A, Hosford WF (1990) Calculations of forming limit diagrams. Metall Trans A 21A:87–94Google Scholar
  9. 9.
    Raghavan KS (1995) A simple technique to generate in-plane forming limit curves and selected applications. Metall and Mater Trans A 26A:2075–2084CrossRefGoogle Scholar
  10. 10.
    Ghosh AK, Hecker SS (1974) Stretching limits in sheet metals: in-plane versus out-of-plane deformation. Metall Trans 5:2161–2164CrossRefGoogle Scholar
  11. 11.
    Ozturk F, Lee D (2005) Experimental and numerical analysis of out-of-plane formability test. J Mater Process Technol 170:247–253CrossRefGoogle Scholar
  12. 12.
    Djavanroodi F, Derogar A (2010) Experimental and numerical evaluation of forming limit diagram for Ti6Al4V titanium and Al6061-T6 aluminum alloys sheets. Mater Des 31:4866–4875CrossRefGoogle Scholar
  13. 13.
    Narayanasamy R, Narayanan SC (2008) Forming, fracture and wrinkling limit diagram for if steel sheets of different thickness. Mater Des 29:1467–1475CrossRefGoogle Scholar
  14. 14.
    Kim J, Kang B-S, Lee (2009) Statistical evaluation of forming limit in hydroforming process using plastic instability combined with FORM. Int J Adv Manuf Technol 42:53–59CrossRefGoogle Scholar
  15. 15.
    Standard test method for determining forming limit curves, ASTM-E-2218-02Google Scholar
  16. 16.
    ISO-12004-2 (2008) Metallic materials-sheet and strip-determination of forming-limit curves—part 2: determination of forming limit curves in the laboratoryGoogle Scholar
  17. 17.
    Dilmec M, Halkaci HS, Ozturk F, Turkoz M (2012) Detailed investigation of forming limit determination standards for aluminum alloys. J Test Eval 41(1):1–12Google Scholar
  18. 18.
    Hashemi R, Ghazanfari A, Abrinia K, Assempour A (2012) Forming limit diagrams of ground St14 steel sheets with different thicknesses. SAE Int J Mater Manuf 5(1):60–64. doi: 10.4271/2012-01-0018 Google Scholar
  19. 19.
    Kleemola HJ, Kumpulainen JO (1980) Factors influencing the forming limit diagram: part II—influence of sheet thickness. J Mech Work Technol 3(3–4):303–311CrossRefGoogle Scholar
  20. 20.
    Svensson C (2004) The influence of sheet thickness on the forming limit curves for austenitic stainless steel. Master Thesis, Örebro University, SwedenGoogle Scholar
  21. 21.
    Kumar DR (2002) Formability analysis of extra-deep drawing steel. J Mater Process Technol 130–131:31–41CrossRefGoogle Scholar
  22. 22.
    Kim Y, Kim C, Lee S, Won S, Hwang S (2003) Forming limits for anisotropic sheet metals. JSME Int J Ser A 46(4):627–634CrossRefGoogle Scholar
  23. 23.
    Yu Z, Lin Z, Zhao Y (2007) Evaluation of fracture limit in automotive aluminium alloy sheet forming. Mater Des 28:203–207CrossRefGoogle Scholar
  24. 24.
    Boogaard T (2002) Thermally enhanced forming of aluminium sheet modeling and experiments. Universiteit Twente Ph.D. Thesis., The NetherlandsGoogle Scholar
  25. 25.
    Keeler SP, Brazier WG (1977) Relationship Between laboratory material characterization and press shop formability. Microalloying 75 Proceedings 517-528. Union Carbide Corp., New YorkGoogle Scholar
  26. 26.
    Zadpoor AA, Sinke J, Benedictus R (2009) The effects of thickness on the formability of 2000 and 7000 series high strength aluminum alloys. Key Eng Mater 410–411:459–466CrossRefGoogle Scholar
  27. 27.
    Tseng HC, Hung C, Huang CC (2010) An analysis of the formability of aluminum/copper clad metals with different thicknesses by the finite element method and experiment. Int J Adv Manuf Technol 49(9–12):1029–1036CrossRefGoogle Scholar
  28. 28.
    Hosford WF, Duncan JL (1999) JOM 51:39CrossRefGoogle Scholar
  29. 29.
    Jalinier JM, Schmitt JH (1982) Damage in sheet metal forming-II. Plastic instability. Acta Metall 30(9):1799–1809CrossRefGoogle Scholar
  30. 30.
    Zadpoor AA, Sinke J, Benedictus R (2008) Comparative study of the formability prediction models for high-strength aluminum alloys. 9th International Conference on Technology of Plasticity (ICTP 2008), Gyengju, South Korea, 1258Google Scholar
  31. 31.
    Elwin LR (1990) ASM handbook volume 2, properties and selection: nonferrous alloys and special-purpose materials, introduction to aluminum and aluminum alloys. ASM International, AmericaGoogle Scholar
  32. 32.
    Takuda H, Hatta N (1998) Numerical analysis of the formability of an aluminum 2024 alloy sheet and its laminates with steel sheets. Metall Mater Trans A 29A:2829–2834CrossRefGoogle Scholar
  33. 33.
    Hursman TL (1978) Development of forming limit curves for aerospace aluminum alloys. Formability topics-metallic materials. ASTM STP 647. In: Niemeler BA, Schmieder AK and Newby JR (eds) American Society for Testing and Materials, 122–149Google Scholar
  34. 34.
    Ozturk F, Dilmec M, Turkoz M, Ece RE, Halkaci HS (2009) Grid marking and measurement methods for sheet metal formability. 5th International Conference and Exhibition on Design and Production of Machines and Dies/Molds, Aydın, Turkey, 41-49Google Scholar
  35. 35.
    Merklein M, Kuppert A, Geiger M (2010) Time dependent determination of forming limit diagrams. CIRP Ann Manuf Technol 59(1):295–298CrossRefGoogle Scholar
  36. 36.
    Vallellano C, Morales D, Garcia-Lomas FJ (2008) A study to predict failure in biaxially stretched sheets of aluminum alloy 2024-T3. Mater Manuf Process 23:303–310CrossRefGoogle Scholar

Copyright information

© Springer-Verlag London 2012

Authors and Affiliations

  • Murat Dilmec
    • 1
  • H. Selcuk Halkaci
    • 2
  • Fahrettin Ozturk
    • 3
    • 4
  • Haydar Livatyali
    • 5
  • Osman Yigit
    • 6
  1. 1.Department of Mechanical Engineering, Faculty of EngineeringNecmettin Erbakan UniversityMeramTurkey
  2. 2.Department of Mechanical Engineering, Faculty of EngineeringSelcuk UniversityKonyaTurkey
  3. 3.Department of Mechanical Engineering, Faculty of EngineeringNigde UniversityNigdeTurkey
  4. 4.Department of Mechanical EngineeringThe Petroleum InstituteAbu DhabiUAE
  5. 5.TÜBİTAK Marmara Research CenterEnergy InstituteGebze-KocaeliTurkey
  6. 6.Department of Mechanical Engineering, Faculty of Engineering and Natural SciencesYildirim Beyazit UniversityAnkaraTurkey

Personalised recommendations