Springback is one of the major concerns as more advanced high strength steels are used in the automotive industry. Unlike FEA forming simulation, FEA springback simulation is not widely used in the production due to its poor accuracy. One of the reasons for this is that some complex material behaviors are not fully considered in the FEA simulations.In this study, a number of experiments were conducted to study the unloading behavior of steels with different pre-strain levels. Unloading modulus and related damage parameters at 1%, 2% and 5% pre-strain are calculated for 14 different steel grades from the experimental data to consider the inelastic effects during unloading. The unloading modulus was found to be 10% to 20% lower than the Young's modulus. FEA springback simulations were conducted for a benchmark test with two steel grades. Simulated springback results are compared with the experimental data. Results show that the simulation accuracy is significantly improved by incorporating the unloading modulus concept instead of conventional elastic-plastic model.


    Access

    Check access

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Unloading Modulus on Springback in Steels


    Additional title:

    Sae Technical Papers


    Contributors:
    Wong, Chris (author) / Zhu, Hong (author) / Huang, Liang (author)

    Conference:

    SAE 2004 World Congress & Exhibition ; 2004



    Publication date :

    2004-03-08




    Type of media :

    Conference paper


    Type of material :

    Print


    Language :

    English




    Unloading modulus on springback in steels

    Zhu,H. / Huang,L. / Wong,C. et al. | Automotive engineering | 2004


    Unloading Modulus on Springback in Steels

    Zhu, H. / Huang, L. / Wong, C. et al. | British Library Conference Proceedings | 2004


    The Effective Unloading Modulus for Automotive Sheet Steels

    Levy, B. S. / Mikalsen, C. / Van Tyne, C. J. et al. | SAE Technical Papers | 2006


    The effective unloading modulus for automotive sheet steels

    Levy,B.S. / van Tyne,C.J. / Moon,Y.H. et al. | Automotive engineering | 2006


    Experimental Investigation of Springback of Dual-Phase Steels

    Ragai, Ihab / Nemes, James A. | SAE Technical Papers | 2005