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Stamping parts processing plants, processing auto and motorcycle parts, stainless steel stamping parts, special-shaped parts, in the process of automotive stamping parts processing, the bending rebound of U-shaped stamping parts is the key content of the bending process research; 1. U-shaped stamping parts will bend The law Since the flat plate of the stamping part has been bent into a U-shaped part, compared with the same material thickness, the rebound angle is reduced, and the fillet radius of the punch increases. How much is the fillet radius of the punch? After analyzing various data, it is found that the bending law of U-shaped stamping parts is related to the following factors: 1. The mechanical properties of the material and the rebound angle of the material are proportional to the yield point of the material, and inversely proportional to the elastic modulus. 2. Relative bending The radius r/t is the bending radius of the workpiece along the length direction, and t is the height of the U-shaped part. The smaller the r/t value, the greater the degree of deformation of the rounded area. Under the same other conditions, the springback angle varies with Increases with the increase of r/t; 2. U-shaped bending stamping parts have less springback than V-shaped parts, the shape of the workpiece is complicated, and the parts are more involved in each other, making springback more difficult; 3. In terms of mold design, U The greater the gap between the convex and concave molds of the bending mold, the greater the springback of the parts after unloading. Because of the excessive mold gap, the degree of adhesion between the material and the mold is reduced, and the radial constraint on the straight edge of the bending part is also reduced. In this way, under the same other conditions, the larger the gap, the smaller the plastic deformation of the bending part, and the greater the springback of the part after unloading. For U-shaped bending stamping parts, the springback The opening depth of the concave die increases and decreases, and the smaller the die gap, the smaller the springback;