在金属板材成型中，坯料经拉延成型后得到无缺陷与无多余材料的零件，意味着坯料设计必须合理.由于坯料的非均匀流动和各向异性特性产生的凸耳与不均匀法兰，成型零件与目标零件存在形状差异.为获得合理的坯料，提出节点网格映射方法.结合逆有限元分析和增量分析，根据映射关系和材料点流动趋势优化坯料形状.为了验证提出的方法，分别对方盒件成型和某电动车B柱成型进行坯料设计.结果表明，对于较为复杂的工业零件，所提出的方法经过有限次优化后可得到合理坯料形状，所需的目标零件形状与采用合理坯料成型后的形状一致.
The transformation of the sheet into products without failure and excess of material in a sheet metal forming operation means that the blanks should be correctly designed. Due to the earing or non-uniform flange in sheet metal forming, caused by non-uniform material flow and planar anisotropy in the sheet, shape differences exist between the forming parts and target parts. In order to obtain a reasonable blank, the node mesh mapping method is proposed. Combining with the inverse finite element analysis and incremental analysis, the blank shape is optimized according to the mapping relationship and the flow tendency of material points. To test the proposed method, blank shape optimizations in the forming processes of a square box part and an electric car B-pillar are presented respectively. The results show that for more complex industrial parts, the method proposed in this paper can obtain a reasonable blank shape after a finite optimization, and the required shape of the target part is consistent with the shape after forming with a reasonable blank.
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