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How to deal with the rebound of precision shrapnel during bending?

There are two ways to control the rebound of precision shrapnel. One is the overcompensation method and the other is the process control method. According to the trend of rebound, the compensation angle that is consistent with the expected rebound is created in the mold, or the overshooting of the punch is controlled. This is the so-called compensation method. This is a widely used method to control the rebound of precision domes. However, in the presence of complicated curved products and high-precision requirements, there is a limit to the accuracy of springback control because it is difficult to accurately estimate the amount of springback.

The second approach to change the stress state of the sheet, the process control method is used to control the rebound. Usually this process includes: stamping, bending, thermal bending. During the stamping process, the additional stress in the thickness direction changes the stress distribution in the area of bending deformation. The rebound of the sheet is controlled by applying a tangential tensile deformation and bending moment at the bend of the precision sheet.