What are the reasons for the appearance defects of stamping parts?
When processing stamping parts, problems such as impact lines, slip lines, collapses, dark pits, and surface distortions occasionally occur. For stamping parts, the appearance of defects cannot be allowed to appear. How is this situation? Forming?
1. The main reason for the impact line and the slip line is the impact of the stamping process. After the sheet metal and the die are not in contact, the surface scratches are generated by mutual friction at the stress concentration point. Collapse, dark pit.
- The torsion of the surface is mainly caused by the incomplete deformation of the parts. The local material has a small strain during use, and the external force will release a large number of defects that appear later.
First, how to eliminate these defects?
1. To eliminate the impact line, you can change the stamping fillet, die fillet, increase the drawing depth, change the pressing surface and other methods.
2. By changing the product shape (left and right symmetry) and increasing the resistance, the slip line can be eliminated.
3. Eliminate the collapse and surface distortion, understand the stress gradient level of the parts in the deformation area, and try to ensure the uniformity of the plastic deformation of the product. At the same time, by increasing the resistance and improving the local shape strain.
With the continuous innovation of cae simulation and application with technological progress, more and more shortcomings can be found in the simulation. For example; you can understand the flow of the material through the formed tangent shift field to help better solve the defects generated when the part is formed.