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The macro model and micro model are of the same deformation process in the upsetting process, namely, the time spent on the same amount of upsetting is equal. Then, the amount of upsetting in the macroscopic model corresponding the shrinkage closure in the representative feature body was used to determine the closure order of shrinkage in the region of these feature points. The upsetting model was established by the software DEFORM-2D. Due to the workpiece with symmetry, the limited feature points on the workpiece were selected, so the finite element simulation was carried out by changing the temperature, strain rate and shrinkage size. Furthermore, the appropriate amount of upsetting was selected, and it was found that the influence of temperature and shrinkage size on the closure order of each feature point was relatively small, but the variation of strain rate made the feature point closure order change significantly. In comparison with the actual condition, the deformation zone was basically identical under the same condition. Thus, the closed order of shrinkage in different deformation zones under various forming environment was verified.
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