基于晶体塑性有限元的转向架盖板压形回弹预测

Springback prediction on bogie cover plate pressing based on crystal plastic finite element

针对S355J2W钢板材由于具有显著的各向异性而使其在模具压形工艺中的回弹难以预测的问题。以高速动车组转向架侧梁上盖板成形为例,对S355J2W钢的晶粒与织构进行了分析并对其各向异性进行了量化,获得了材料晶体塑性本构模型的关键参数,并使用晶体塑性有限元方法评估了其各向异性的力学性能以及Hill48屈服准则的模型参数。建立了转向架侧梁上盖板压形过程仿真模型,分别采用Von Mises及Hill48屈服准则来模拟工件成形后的应力释放及回弹效应,并开展了侧梁上盖板压形实验进行验证,实验结果和仿真结果吻合。各向同性模型和各向异性模型预测结果的对比表明,采用各向异性材料模型可以更准确地预测侧梁上盖板的回弹。

Aiming at the problem that the springback of S355J2W steel plate in the die pressing process was difficult to predict due to its remarkable anisotropy,for the forming of side beam upper cover plate for high-speed EMU bogie,the grain and texture of S355J2W steel were analyzed,and the anisotropy of the material was quantified.Then,the key parameters of crystal plastic constitutive model were obtained,and the anisotropy mechanical properties and the model parameters of Hill48 yield criterion were evaluated by crystal plastic finite element method(CPFEM).Furthermore,a simulation model of the pressing process for bogie upper cover plate of side beam was established,and the stress release and springback effect of the workpiece after forming were simulated by Von Mises and Hill48 yield criterion.Meanwhile,the side beam upper cover plate pressing test was carried out to verify the results,and the test results were consistent with the simulation results.The comparison of the prediction results between the isotropic and anisotropic models shows that the anisotropic material model can predict the springback of the side beam upper cover plate more accurately.