弯曲件,一般来说模具设计比较简单,但弯曲件的精度除直接受模具工作部分结构和回弹影响外,弯曲件展开长度计算准确程度是关键,它是正确设计模具的依据。决定弯曲件展开长度的方法一般根据应变中性层在弯曲前后长度不变的特点确定展开长度,即常说的概算法。而对有圆角半径的弯曲件,则分为直边部分与弯曲部分用中性层的长度和进行计算(图1) Bending parts, in general, the mold design is relatively simple, but the accuracy of the bending parts in addition to directly affected by the working part of the mold structure and the impact of springback, the bending part of the calculation accuracy is the key to the correct length, it is the basis for the correct design of the mold. Determine the length of the curved part of the expansion method is generally based on the length of the strain neutral layer before and after bending to determine the characteristics of the expansion of the length, the so-called general algorithm. For curved parts with rounded radii, the straight part and the bent part are divided by the length of the neutral layer and calculated (Figure 1)