前言 在同一加工条件下,弯曲弹性变形的回弹随着原材料的板厚及其特性而变化,这是降低尺寸精度的主要原因。在U形弯曲加工中,正在开发弯曲之后在工件的宽度方向上施加压缩力的压缩弯曲加工法和在折边上端面施加压缩力的类似轴弯曲等方法,作为减少弹性变形回弹的手段。这样可以改变弯曲部分的应力分布,作为抑制弹性变形回弹的 Preface Under the same processing conditions, the springback of bending elastic deformation varies with the thickness of the raw material and its characteristics, which is the main reason for reducing the dimensional accuracy. In the U-shaped bending, a method of reducing the elastic deformation springback is being developed, such as a compression bending method that applies a compressive force in the width direction of the workpiece after bending and a similar axis bending method that applies a compressive force to the flanged upper end surface. This can change the stress distribution of the curved portion, as a springback to suppress the elastic deformation