考虑数控渐进成形中层间距对成形质量的影响,提出了一种基于等残余高度的、并对成形角不同曲面区域生成不等层间距的等高线轨迹生成方法。首先生成等残余高度的等高线轨迹,然后在大成形角、大层间距区域中插入等高线来优化层间距。最终生成能满足等残余高度要求、并能通过减小成形力来减小反弹变形的轨迹。数值模拟分析与试验结果表明,该方法生成的不等层间距成形轨迹与等残余高度轨迹相比,成形件所受的等效应变均匀性好,成形件轮廓精度高,能够获得较好的工艺质量。
Considering the influences of layer distance on forming quality in CNC incremental forming,a method to generate the contour path with unequal layer distance was proposed based on the constant scallop height and surface region with different forming angles.First,the forming paths with constant scallop height were generated.Then,the contour paths were inserted in to the region with large forming angle and large layer distance to optimize the layer distances.Finally,the forming paths were generated,which might meet the requirements of scallop height and reduce the forming forces and the springback deformations.The results of numerical simulations and forming experiments show that the unequal layer distance forming path generated by this method has better uniformity of effective strain,higher forming accuracy and better process quality than that of constant scallop height path.