基于一步逆成形法的毛坯边界线精细算法

Fine algorithm of blank boundary line based on one-step inverse forming method

在板料冲压成形技术中,一步逆成形法可以快速获得较小零件毛坯的尺寸和边界线。为了加快设计周期、提高计算效率,针对大体积的模型提出了毛坯边界线精细算法。本算法基于一步逆成形法的有限元解获得的零件初始构形,进一步给出了一种基于粗网格的零件毛坯边界线的精细算法。该算法经过投影、映射和插值3个过程,可以获得与零件曲面特征线相对应的边界线。算例表明,全部边界线具有较高的精度,有利于判断毛坯内部形状的合理性,提高最终零件的成形精度。该算法在保证一步逆成形法具有高效性的基础上,显著提高了计算精度,针对大体积模型的毛坯反算具有较高的应用价值。

In the sheet metal stamping technology,the size and boundary line of smaller part blank can be obtained quickly by one-step inverse forming method. In order to speed up the design cycle and improve the calculation efficiency,the fine algorithm of blank boundary line was proposed for the large volume model. Then,based on the finite element numerical solution of one-step inverse forming method,the initial configuration of part was obtained,and a fine algorithm of blank boundary line for part based on rough mesh was given. Furthermore,through three processes of projection,mapping and interpolation,the boundary line corresponding to the feature line of part surface was obtained. The example shows that all the boundary lines have high accuracy to judge the rationality of the internal shape for blank helpfully and improve the forming accuracy of the final part. On the basis of guaranteeing the high efficiency of one-step inverse forming method,the algorithm significantly improves the calculation accuracy and has a high application value in the blank back calculation of large volume model.