The stress state-dependent plastic anisotropy of sheet metals has drawn significant attention. Nevertheless, existing phenomenological plasticity models limitedly capture the distinctive yield strengths and plastic flow (r-values) under a wide range of stress states covering uniaxial tension (UT), equi-biaxial tension (EBT), uniaxial compression (UC), plane strain tension (PS), and pure shear (SH). This study aims to propose a new anisotropic-asymmetric plasticity model with enhanced flexibility based on the non-associated flow rule. The yield function is formulated based on the additive coupling of two stress potentials: coupling between a new anisotropic pressure-sensitive fourth-order polynomial function, and an isotropic stress invariant-based function. Then, all the anisotropic/asymmetric parameters of the yield function can be analytically identified from 7 yield stresses measured from UT tests along 0°, 45°, and 90° to the rolling direction (RD), UC tests along 0° and 90° to the RD, EBT test, and SH test along 45° to the RD. Within the scheme of no-associated flow rule, a new asymmetric fourth-order plastic potential function is proposed to analytically describe the plastic flow of sheet metals under UT, UC, EBT and SH. The additively coupled stress invariant-based term is introduced to adjust the yield stresses and plastic flow under biaxial tension including PS, which leads to an independent description of the yield stresses and plastic strain directions under SH and PS states. Various automotive sheet metals such as advanced high-strength steels, aluminum alloy, and magnesium alloy with strong asymmetry and anisotropy are investigated to verify the proposed yield criterion. The results demonstrate remarkable flexibility and accuracy of the proposed yield criterion against other existing models. Evolving yield surface and plastic potential of a quenching and partitioning steel are accurately captured by the proposed anisotropic-asymmetric yield criterion. Besides, the advantages of new model are further discussed in terms of the proof of yield surface convexity, identified parameters, and the regulation between anisotropy and isotropy in comparison with existing multiplicative coupling method.

金属板材的应力状态相关塑性各向异性引起了人们的极大关注。然而，现有的现象学塑性模型在广泛的应力状态下有限地捕获了独特的屈服强度和塑性流动（r 值），包括单轴拉伸（UT）、等双轴拉伸（EBT）、单轴压缩（UC）、平面应变张力 (PS) 和纯剪切 (SH)。本研究旨在提出一种新的基于非关联流动规则的具有增强灵活性的各向异性非对称塑性模型。屈服函数是基于两个应力势的加性耦合制定的：新的各向异性压力敏感四阶多项式函数与各向同性应力不变函数之间的耦合。然后，屈服函数的所有各向异性/不对称参数都可以从 7 个屈服应力中分析确定，这些屈服应力从 UT 测试沿 0°、45° 和 90° 到轧制方向 (RD)，UC 测试沿 0° 和 90° 到轧制方向 (RD) RD、EBT 测试和 SH 测试沿 45° 到 RD。在无关联流动规则方案中，提出了一种新的不对称四阶塑性势函数来分析描述金属板在 UT、UC、EBT 和 SH 下的塑性流动。引入基于附加耦合应力不变量的项来调整包括 PS 在内的双轴拉伸下的屈服应力和塑性流动，从而独立描述 SH 和 PS 状态下的屈服应力和塑性应变方向。先进高强钢、铝合金等各种汽车板材，研究了具有强不对称性和各向异性的镁合金，以验证所提出的屈服准则。结果表明，相对于其他现有模型，所提出的屈服标准具有显着的灵活性和准确性。所提出的各向异性不对称屈服准则准确地捕获了淬火和分配钢不断变化的屈服面和塑性势。此外，与现有的乘法耦合方法相比，新模型在屈服面凸性的证明、识别的参数、各向异性和各向同性之间的调节等方面进一步讨论了新模型的优势。所提出的各向异性不对称屈服准则准确地捕获了淬火和分配钢不断变化的屈服面和塑性势。此外，与现有的乘法耦合方法相比，新模型在屈服面凸性的证明、识别的参数、各向异性和各向同性之间的调节等方面进一步讨论了新模型的优势。所提出的各向异性不对称屈服准则准确地捕获了淬火和分配钢不断变化的屈服面和塑性势。此外，与现有的乘法耦合方法相比，新模型在屈服面凸性的证明、识别的参数、各向异性和各向同性之间的调节等方面进一步讨论了新模型的优点。