考虑各向异性的回转曲面件蠕变时效成形数值模拟与实验

Numerical simulation and experiment of creep aging forming of rotary curved surface parts considering anisotropy

针对铝锂合金回转曲面件蠕变时效成形各向异性问题,开展了基于Barlat91屈服各向异性准则和蠕变各向异性本构模型的回转曲面件蠕变时效成形数值模拟与实验研究。仿真结果表明,构件加载阶段发生塑性变形,呈现出■的塑变各向异性现象;考虑蠕变各向异性行为的构件的蠕变应变分布发生明显改变。进一步通过开展回转曲面件蠕变时效成形实验发现,所建立的蠕变各向异性模型对厚度变化、残余应力分布预测准确;相对于各向同性模型,型面精度的整体预测偏差减小9.3%,焊接边预测偏差减小91.5%,证明了所建铝锂合金蠕变时效各向异性本构模型的准确性和实际应用价值。

Aiming at the creep aging forming anisotropic problems of aluminum-lithium alloy rotary curved surface parts,the numerical sim-ulation and experimental research on creep aging of rotary curved surface parts based on the Barlat91 yielding anisotropy criterion and creep anisotropy constitutive model were carried out.The simulation results show that plastic deformation occurs in the loading stage of the parts,showing the plastic strain anisotropy phenomenon of ■;the creep strain distribution of the parts considering creep anisotropy be-haviors are significantly changed.Furthermore,through the creep aging forming experiments of rotary curved surface parts,it is found that the established creep anisotropy model is accurate to predict the thickness change and residual stress distribution.Relative to the isotropic mod-el,the overall prediction deviation of the profile accuracy is reduced by 9.3%,and the prediction deviation of the weld edge is reduced by 91.5%,which proves the accuracy and practical application value of the established creep aging anisotropic model of aluminum-lithium alloy.