一种基于能量法的冲压回弹预测补偿算法

An energy approach for stamping springback prediction and compensation

冲压零件的回弹会严重影响零件的形状和尺寸精度。通过对模具型面进行调整,从而去除回弹造成的形状误差是目前常用的一种手段。但是这种方法的模具型面设计工作量很大。文章在能量法的基础上,提出了一种预测任意截面形状的回转体零件回弹量的算法。该算法具有较快的计算速度,适用于多次迭代的补偿计算。利用该算法对半球形零件的拉深回弹进行了预测,所得结果与实验结果吻合较好。在此基础上,提出了一种位移调整的算法,通过在回弹预测量的反方向对模具型面进行补偿,可以自动获得补偿后的模具型面。实际计算结果表明,该算法具有较快的迭代速度,对一般形状的回转体零件可以在2次迭代后获得较高的零件精度。

The springback of sheet metal parts has great negative impact on the shape and dimension accuracy. A general approach for diminishing the shape errors caused by springback is adjusting the tooling shapes to the appropriate shapes. But this approach requires a lot of work on tooling geometry design. An energy based method for springback prediction of revolving parts with arbitrary cross-section shapes is presented. This method has the advantage in calculating efficiency and is suitable for compensation calculation. Good agreement is found between the theoretical predictions and the experimental results in the springback of hemispherical parts. Based on the prediction method, an algorithm is developed to automatically acquire compensated tooling shapes. The algorithm compensates the tooling shape in the verse direction of springback by adjusting displacements. The example of tooling shape design using this algorithm shows that high dimension accuracies can be achieved for general revolving parts with arbitrary cross-section shapes after two iterations.