为选择适合于5052铝合金回弹仿真的材料模型，对LS⁃Dyna软件中4个材料模型MAT＿36、MAT＿122、MAT＿125和MAT＿226所采用的屈服准则和硬化模型进行了分析，采用这4个模型对5052铝板U形件的回弹进行了仿真，对回弹过程中圆角区的应力释放进行了讨论。同时，进行了U形件的回弹试验，并与仿真结果进行了比较。结果表明，4个材料模型中，基于Yoshida⁃Uemori随动硬化模型和Barlat’89屈服准则的材料模型MAT＿226具有最好的回弹预测精度，由各向同性硬化模型和Hill’48屈服准则组合的材料模型MAT＿122的回弹预测结果与试验结果的偏差最大。硬化模型对回弹预测精度的影响大于屈服准则的影响。%To select a suitable material model for springback simulation of the 5052 aluminum sheet, the yielding criteria and hardening models used in the four material models,MAT_36, MAT_122, MAT_125 and MAT_226 adopted by LSDYNA software were analyzed. These four material models were used to simulate the springback of a 5052 aluminum U⁃shaped part. The stress relief during springback at the corners and walls of U⁃shaped part was discussed. Springback experiments of the U⁃shaped part were performed, and the obtained data were compared tothe simulation ones. The results indicated that among the four material models, the model, MAT_226, that includes the Balart89 criterion and Yoshida⁃Uemori kinematic hardening model has the highest precision of springback simulation.TheMAT_122modelconsisting ofthe isotropic hardening and Hill’48 yielding criterion gives the lowest precision in springback simulation.Hardening model has greater influence on the precision of springback simulation than the yielding criterion has.
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