精确预测近平面应变载荷下各向异性行为的屈服准则参数识别策略

Parameter Identification Strategy of Yield Criterion for Accurately Predicting Anisotropic Behaviors under Near Plane Strain Loading

随着现代汽车工业对冲压零部件成形精度要求的不断提高,描述商用汽车板材变形行为的模型的精度也必须相应提高。在此背景下,结合当前工业级实验室检测能力,提出一种基于单轴拉伸、等双轴拉伸和近平面应变数据标定先进各向异性屈服准则的参数识别策略。将新提出的校准方法应用于BBC2008屈服准则并与其他几种屈服准则(包括工业界广泛使用的Hill48和Barlat89,以及与BBC2008灵活性相当的Yld2004-18p、Yld2011-27p、Yoshida2013和Poly4*Hosford)进行比较。通过定量评估MP980和SPCE钢以及5182-O和A6XXX-T4铝合金的法平面屈服轨迹、对角线平面剪切屈服轨迹、等双轴和单轴拉伸屈服应力与塑性应变比的预测误差,验证了新参数识别策略的有效性和适用性。结果表明,新方法能够全面提升塑性各向异性方面的描述能力,尤其是对于对角线平面剪切屈服轨迹。不同屈服准则对商用汽车板材各向异性行为的描述能力表现出非常大的差异性。特别地,在使用相同力学性能数据校准屈服准则的前提下,释放指数的潜在调节能力比增加材料参数的数量更加重要。

With the increasing demands for forming accuracy of stamped parts in the modern automobile industries,the accuracy of models describing the deformation behavior of commercial sheet metals should be improved accordingly.In the context,a parameter identification strategy was proposed based upon uniaxial tension,equi-biaxial tension,and near-plane strain data to calibrate advanced anisotropic yield criteria,combined with current industrial laboratory testing capabilities.The newly proposed calibration method was applied to the BBC2008 yield criterion and compared with several other yield criteria,including the widely used Hill48 and Balat89 in the industry,as well as Yld2004-18p,Yld2011-27p,Yoshida2013,and Poly4*Hosford,which had similar flexibility to BBC2008.The effectiveness and applicability of the new parameter identification strategy were verified by quantitatively evaluating the predicted errors of the yield loci in the normal and diagonal planes,equi-biaxial and uniaxial tensile yield stresses,and plastic strain rations for MP980 and SPCE steels,as well as 5182-O and A6XXX-T4 aluminum alloys. The results show that the new method may comprehensively improve the ability to describe plastic anisotropy, especially for diagonal plane shear yield loci. There are significant differences in the ability of different yield criteria to describe the anisotropic behavior of commercial sheet metals. In particular, under the premise of calibrating yield criteria with the same mechanics properties data, releasing the potential adjustment ability of the exponent is more important than increasing the number of material parameters.