Dual-phase (DP) steel has an excellent blend of various mechanical properties; hence it is used immensely in the automotive industries. It is challenging to form high strength DP steel into desirable complex shapes because of their limited formability at room temperature conditions. One of the proven alternatives is warm/hot forming. In-detail investigation of forming limits over DP590 steel has been carried out in present work. Firstly, various constitutive models and yield criteria have been formulated for DP steel at different temperatures and strain rates. The modified Arrhenius (m-A) constitutive model and Barlat 1989 yielding function displayed the best prediction of flow stress and anisotropic yielding behavior, respectively. The experimental forming limits (FLD) were evaluated at 300, 473 and 673 K temperatures using Nakazima tests. The forming limits of the material are improved by approximately 24% on increasing the temperature from 300 to 673 K. The textural analysis of the deformed surface has been done using electron back scattered diffraction (EBSD) studies, and γ fibers are found to be responsible for improvement in the formability of the material. Additionally, Marciniak and Kuczynski (MK) model was used to predict the theoretical FLD using all the possible combinations of constitutive models and yield criteria. Finally, the m-A constitutive model, along with Barlat 1989 yielding function has shown the best prediction for forming limits at all the temperatures. The finite element study has also been performed using mentioned material models for accurate prediction of dome height, surface strain and thickness distribution across the specimens.

双相 (DP) 钢具有多种机械性能的优异混合；因此，它在汽车工业中得到了广泛的应用。将高强度 DP 钢制成所需的复杂形状具有挑战性，因为它们在室温条件下的可成形性有限。一种行之有效的替代方案是温/热成型。在目前的工作中已经对DP590钢的成形极限进行了详细研究。首先，针对不同温度和应变速率下的 DP 钢制定了各种本构模型和屈服标准。修正的 Arrhenius (mA) 本构模型和 Barlat 1989 屈服函数分别显示了对流动应力和各向异性屈服行为的最佳预测。实验成形极限 (FLD) 在 300、473 和 673 K 温度下使用 Nakazima 测试进行评估。将温度从 300 K 提高到 673 K，材料的成形极限提高了约 24%。变形表面的纹理分析已使用电子背散射衍射 (EBSD) 研究完成，发现 γ 纤维是原因以提高材料的可成形性。此外，Marciniak 和 Kuczynski (MK) 模型用于使用本构模型和屈服标准的所有可能组合来预测理论 FLD。最后，mA 本构模型以及 Barlat 1989 屈服函数显示了在所有温度下形成极限的最佳预测。还使用上述材料模型进行了有限元研究，以准确预测整个试样的圆顶高度、表面应变和厚度分布。