In this study, the performance of conventional and advanced constitutive models to the prediction of springback for ultra-high strength steel was assessed. The elasto-plastic behavior of a martensitic steel sheet sample was characterized to assess the conventional stress-strain behavior in uniaxial tension. More advanced tests such as uniaxial compression and tension-compression experiments were conducted to assess the strength-differential (SD) effect and hardening fluctuations during non-linear loading paths (NLLP effect). Three constitutive plasticity models, namely, the conventional isotropic hardening, Yoshida-Uemori (YU) two surface kinematic hardening and pure distortional hardening (HAH₂₀) models were calibrated using an optimization procedure. Then, these models were employed for finite element predictions of springback after forming. The isotropic hardening model does not consider both SD and NLLP effects and the YU model captures only the influence of the NLLP effect. On the other hand, the HAH₂₀ model describes both effects simultaneously. The performance of these models with respect to springback prediction was evaluated using three forming applications: wiper bending, C-rail drawing and Roof-Side-Rail crush forming. This work indicates that the HAH₂₀ model is the best candidate for the prediction of forming and springback for such martensitic steel because of its ability to consider both SD and NLLP effects. However, the conventional isotropic hardening model led to results in good agreement with those obtained using the HAH₂₀ model in specific cases. The reason, discussed in detail in this article, is likely due to the compensation of the permanent softening due to load reversal by the higher flow stress due to the SD effect.

在这项研究中，评估了传统和先进的本构模型在预测超高强度钢回弹方面的性能。对马氏体钢板样品的弹塑性行为进行了表征，以评估单轴拉伸下的常规应力-应变行为。进行了更高级的测试，例如单轴压缩和拉伸压缩实验，以评估非线性加载路径（NLLP 效应）期间的强度差异 (SD) 效应和硬化波动。三种本构塑性模型，即常规各向同性硬化、Yoshida-Uemori (YU) 两面运动硬化和纯变形硬化 (HAH ₂₀) 模型使用优化程序进行了校准。然后，这些模型被用于成形后回弹的有限元预测。各向同性硬化模型不考虑 SD 和 NLLP 效应，YU 模型仅捕获 NLLP 效应的影响。另一方面，HAH ₂₀模型同时描述了这两种效应。使用三种成型应用评估了这些模型在回弹预测方面的性能：刮水器弯曲、C 形导轨拉伸和车顶侧轨挤压成型。这项工作表明 HAH ₂₀模型是预测此类马氏体钢的成形和回弹的最佳候选者，因为它能够同时考虑 SD 和 NLLP 效应。然而，传统的各向同性硬化模型导致的结果与在特定情况下使用 HAH _{20模型获得的结果非常一致。}本文详细讨论的原因可能是由于 SD 效应导致的更高流动应力对负载反转引起的永久软化的补偿。