金属弯曲变形回弹现象是影响工件尺寸精度的一个主要因素。因此,如何克服回弹现象是值得研究的一个课题。我厂锻工车间生产的敞车杠杆托架(见图1)材质A3,过去用旧胎型冷压,保证不了90°弯度的要求,压制后,还要经过一道手工整修工序,生产效率低。原先,我们采用“超限法”(见图2),即增加变形量(补偿角度β)以抵消回弹量。这种方法有如下缺点:(1)工件夹于上胎,不易仰料;(2)β值因料而异很难计算准确,弯曲角度误差大,质量不稳定。后来通 Metal bending deformation rebound phenomenon is a major factor affecting the dimensional accuracy of the workpiece. Therefore, how to overcome the rebound phenomenon is worth studying a topic. The gondola lever bracket made by our factory forging workshop (see Figure 1) is made of A3 material. In the past, the old tire type was cold-pressed to ensure that the 90 ° camber was not required. After pressing, it was subjected to a manual renovation process with low production efficiency. Originally, we used the “overrun method” (see Figure 2), which increased the amount of deformation (compensation angle β) to offset the amount of rebound. This method has the following disadvantages: (1) the workpiece is caught in the upper tire, not easy to back material; (2) β value varies according to the material is difficult to calculate accurately, the bending angle error, the quality is unstable. Later pass