Causes of surface scratches on metal stamping parts

1. When performing continuous bending of soft materials such as copper and aluminum alloys, metal particles or scum are easy to attach to the surface of the working part, causing larger scratches on the workpiece. At this time, the shape of the working part should be carefully analyzed and studied. Lubricating oil and other conditions make the blanks better not to appear particles and scum, and even scratches.

2. When the bending direction of the Metal Stamping is parallel to the rolling direction of the material, cracks will occur on the surface of the workpiece, which will reduce the surface quality of the workpiece. When metal stamping and bending are performed at two or more positions, the angle between the metal stamping and bending direction and the rolling direction should be ensured as much as possible.

3. When the burr surface is used as the outer surface for metal stamping and bending, the parts are prone to cracks and scratches; therefore, the burr surface should be used as the inner surface of the metal stamping and bending when the metal is stamped and bent.

4. The corner radius of the die is too small, and impact marks appear on the bending parts of the metal stamping. Polish the die and enlarge the corner radius of the die to avoid scratches on the metal stamping and bending parts.

5. The gap between the convex and concave molds should not be too small. Too small a gap will cause thinning and scratches. In the stamping process, always check the change of the mold gap.

6. When the depth of the punch into the concave mold is too large, the surface of the part will be scratched. Therefore, the depth of the punch into the concave mold should be appropriately reduced while ensuring that it is not affected by rebound.

7. In order to make the parts meet the accuracy requirements, the metal stamping and bending dies are often used at the bottom of the pressing material. When the metal is stamped and bent, the springs on the pressing plate, the positioning pin holes, the supporting plate and the return hole will all be pressed into the pressed material. The mark should be adjusted.